Example Annual Report

Colorado Water Institute
Annual Technical Report
FY 2012

Colorado Water Institute Annual Technical Report FY 2012

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Introduction
Colorado Water Institute Annual Report for the period:
March 1, 2012 – February 28, 2013

Water research is more pertinent than ever in Colorado. Whether the project explores the effects of
decentralized wastewater treatment systems on water quality, optimal irrigation scheduling, household
conservation patterns, the effects of wastewater reuse on turfgrass, the economics of water transfers, or
historical and optimal streamflows, water is a critical issue. In a headwaters state where downstream states
have a claim on every drop of water not consumed in the state, the quality and quantity of water becomes
essential to every discussion of any human activity.
The Colorado Water Institute (CWI), an affiliate of Colorado State University (CSU), exists for the express
purpose of focusing the water expertise of higher education on the evolving water concerns and problems
being faced by Colorado citizens. We are housed on the campus of CSU but work with all public institutions
of higher education in Colorado. CWI coordinates research efforts with local, state, and national agencies and
organizations. State funding currently allows CWI to fund research projects at CSU, the University of
Colorado, University of Northern Colorado, and Colorado School of Mines.
Our charges this year included requests from the legislature and state and federal agencies. The Colorado
Legislature passed House Bill 12-1278, requiring the Colorado Water Institute to conduct a comprehensive
study of groundwater utilization in the South Platte River Basin. The Colorado Department of Natural
Resources requested our assistance in engaging researchers and Extension in the public discussions of water
quantity issues around the state. Water Roundtables in designated water basins elicited input from
stakeholders with the goal in mind of creating an environment for water sharing arrangements in the state. In
addition, CWI and the Colorado Department of Agriculture are co-chairing the State’s agricultural drought
impact task force.
CWI serves to connect the water expertise in Colorado’s institutions of higher education to the information
needs of water managers and users by fostering water research, training students, publishing reports and
newsletters, and providing outreach to all water organizations and interested citizens in Colorado.

Introduction

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Research Program Introduction

Research Program Introduction
The Colorado Water Institute funded 2 faculty research projects, 9 student research projects, and 1 internship
this fiscal year. The Advisory Committee on Water Research Policy selected these projects based on the
relevancy of their proposed research to current issues in Colorado.
Under Section 104(b) of the Water Resources Research Act, CWI is to plan, conduct, or otherwise arrange for
competent research that fosters the entry of new scientists into water resources fields, expands understanding
of water and water-related phenomena (or the preliminary exploration of new ideas that address water
problems), and disseminates research results to water managers and the public. The research program is open
to faculty in any institution of higher education in Colorado that has demonstrated capabilities for research,
information dissemination, and graduate training to resolve State and regional water and related land
problems. The general criteria used for proposal evaluation included: (1) scientific merit, (2) responsiveness to
RFP, (3) qualifications of investigators, (4) originality of approach, (5) budget, and (6) extent to which
Colorado water managers and users are collaborating.
Active NIWR projects and investigators are listed below:

Faculty Research
1. Adjoint Modeling to Quantify Stream Flow Changes Due to Aquifer Pumping, Roseanna Neupauer,
University of Colorado, $117,847 (104g)
2. Water Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky Mountain West: Heavy
Metals and Disinfection Byproducts, John McCray, Colorado State University, $140,162 (104g)

Student Research (Faculty Advisor in Parenthesis)
1. Assessing the Benefits and Drawbacks of Different Institutional Arrangements to Enhancing Forest
and Water Ecosystem Services and Ecosystem Services Markets in Colorado, Heidi Huber-Stearns
(Cheng and Goldstein), Colorado State University, $5,000 (104b)
2. Structural and Functional Controls of Tree Transpiration in Front Range Urban Forests, Edward
Gage (Cooper), Colorado State University, $5,000 (104b)
3. Winter Precipitation Variability in the Colorado Rocky Mountains, Andrew Muniz (Doesken),
University of Northern Colorado, $5,000 (104b)
4. Reconstructing a Water Balance for the San Luis Valley: Streamflow Variability, Change, and
Extremes in a Snowmelt Dominated Internal Drainage Basin, Niah Venable (Fassnacht), Colorado
State University, $4,945 (104b)
5. The Short and Long-Term Impacts of Drought on the Structure of Regional Economics: Investigating
6.
the Farm Supply Chain, Ron Nelson (Goemans and Pritchett), Colorado State University, $5,000
(104b)
7. Quantifying Risks Producers Face when Entering Agricultural Water Lease Contracts, Larisa Serbina
(Goemans and Pritchett), Colorado State University, $5,000 (104b)
8. Thermal Preference of Age-0 Stonecats (Noturus Flavus): Are Thermal Water Quality Standards
Protective for this Species?, Adam Herdrich (Myrick), Colorado State University, $4,858 (104b)
9. Biowin Simulation to Assess Alternative Treatment Units for a Local Wastewater Treatment Plant to
Meet the New Effluent Nutrient Regulations, Keerthivasan Venkatapathi (Omur-Ozbek), Colorado
State University, $5,000 (104b)
10. Using Water Chemistry to Characterize the Connection between Alluvial Groundwater and
Streamflow Water under Argumentation at the Tamarack Ranch State Wildlife Area, Colorado, Jason
Roudebush (Stednick), Colorado State University, $5,000 (104b)
Research Program Introduction

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Research Program Introduction

Internships
1. MOWS - Modeling of Watershed Systems, Steve Regan, USGS, $20,000
2. CWCB Interns – Craig Godbout (Colorado State University), Andrew Baessler (University of
Colorado – Denver), Matthew Baessler (University of Colorado – Denver), Jesse Hickey
(Metropolitan State University of Denver)
For more information on any of these projects, contact the PI or Reagan Waskom at CWI. Special
appreciation is extended to the many individuals who provided peer reviews of the project proposals.

Internships

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Adjoint Modeling to Quantify Stream Flow Changes Due to Aquifer Pumping

Adjoint Modeling to Quantify Stream Flow Changes Due to
Aquifer Pumping
Basic Information
Title: Adjoint Modeling to Quantify Stream Flow Changes Due to Aquifer Pumping
Project Number: 2009CO195G
Start Date: 9/1/2009
End Date: 8/31/2012
Funding Source: 104G
Congressional District: Colorado - 2
Research Category: Ground-water Flow and Transport
Focus Category: Groundwater, Surface Water, None
Descriptors: Stream Depletion, Adjoint Model, Modeling
Principal Investigators: Roseanna M Neupauer

Publications
1. Neupauer, Roseanna M, 2011, "Adjoint Modeling to Quantify Stream Flow Changes Due to
Pumping," pg. 16-17 of Colorado Water, Volume 28 issue 2.
2. Neupauer, Roseanna M, 2011, "Adjoint Modeling to Quantify Stream Flow Changes Due to
Pumping," pg. 16-17 of Colorado Water, Volume 28 issue 2.
3. Neupauer, Roseanna M, 2011, "Adjoint Modeling to Quantify Stream Flow Changes Due to
Pumping," pg. 16-17 of Colorado Water, Volume 28 issue 2.
4. Griebling, S.A. and R.M. Neupauer, 2012, "Adjoint Methodology to Simulate Stream Depletion due
to Pumping in a Non-linear Coupled Groundwater and Surface Water System", Computational
Methods in Water Resources.
5. Lackey, G., R.M. Neupauer, and J. Pitlick, 2013, "Effects of varying stream channel conductance on
siting new pumping wells in an aquifer", 2013 World Environmental and Water Resources Congress,
American Society of Civil Engineers.
6. Lackey, G., R.M. Neupauer, and J. Pitlick, 2013, "Effects of spatial and temporal variations of
streambed hydraulic conductivity on stream depletion calculations", MODFLOW and More
Conference.
7. Neupauer, R.M. and S.A. Griebling, 2013, "Comparison of forward and adjoint approaches to
calculate stream depletion with application to the Upper San Pedro Basin", MODFLOW and More
Conference.

Adjoint Modeling to Quantify Stream Flow Changes Due to Aquifer Pumping

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Adjoint Modeling to Quantify Streamflow Changes Due to Aquifer Pumping
Roseanna M. Neupauer, University of Colorado
The purpose of this project is to develop an adjoint modeling methodology to quantify stream depletion
due to aquifer pumping. The methodology can be used to directly quantify stream depletion for a well at
any location in the aquifer. The benefit of the adjoint approach is that with one simulation of the adjoint
model, stream depletion can be calculated for a well at any location in the aquifer. If, for example,
multiple locations are being considered for a new well, stream depletion can be calculated using
standard modeling approaches; however, one simulation is required for each possible well location. In
the adjoint approach, the same information can be obtained with a single simulation. Thus the adjoint
approach is less computationally intensive.
Prior Work
Prior work on this project involved the development and testing of the adjoint theory for confined and
unconfined aquifers for two different cases:
1. weak coupling between the river and aquifer. In this case, the river head is assumed to be
unaffected by pumping.
2. strong coupling between the river and aquifer. In this case, the river head decreases as a result
of pumping.
We use MODFLOW as the groundwater flow simulator for all cases. Case 1 uses the MODFLOW River
(RIV) package. In this case, the adjoint equation has the same form as the forward equation, so
MODFLOW can be used directly to solve the adjoint equation, with modifications only to the
interpretation of the values in some of the input and output files. Case 2 uses the MODFLOW Stream
(STR) package. For this case, the adjoint equations have a slightly different form than the forward
equations, so we modified the source code for the STR package, and we also modified the interpretation
of values in some of the input and output files.
Work Completed June 2012 – May 2013
The work completed between June 2012 and May 2013 followed three different themes. The first
theme was continued testing and modification of the adjoint method for the MODFLOW STR package
and preparation of journal articles on this topic. This work includes the testing of the method on the
Upper San Pedro River Basin, using a USGS model developed for the site. The Upper San Pedro Basin
system is more complex than the hypothetical aquifers we were using as test cases, so we had to
develop the adjoint equations for this more complex system, and we had to develop the approach for
solving the new adjoint equations in the MODFLOW framework. The additional complexities include
evapotranspiration, tributaries, drains, and the use of the Layer Property Flow package. The theory has
been developed and tested. It was published in one proceedings paper (Griebling and Neupauer 2012a)
and is the subject of a journal article that is under review for publication in Water Resources Research
(Griebling and Neupauer, 2013). The testing of the method on the Upper San Pedro River Basin is not
yet complete, but is expected to be completed during the summer 2013. One presentation (Griebling
and Neupauer, 2012b) and one proceedings paper (Neupauer and Griebling, 2013) document
preliminary results of the San Pedro application.
The second theme of work on this project is an investigation of the effects of streambed hydraulic
conductivity on stream depletion. Most modeling investigations that estimate stream depletion assume
a homogeneous streambed and use an assumed value of the streambed conductivity, rather than taking
measurements. The two main findings of our investigations demonstrate that

1. Within the range of typical streambed hydraulic conductivity values, the stream depletion
estimates are sensitive to the selected value of streambed hydraulic conductivity for the middle
of this range. At the high end and low end of the streambed hydraulic conductivity range,
stream depletion may be relatively insensitive to the selected homogeneous value of streambed
hydraulic conductivity.
2. Stream depletion is sensitive to the heterogeneity patterns of the streambed hydraulic
conductivity. Stream depletion is higher for wells placed near high conductivity sections, and
lower for wells placed near low conductivity sections.
This work has been presented at two conferences (Lackey et al., 2012, 2013c) and included in two
conference proceedings papers (Lackey et al., 2013a,b).
The third theme of the current work is an extension of the adjoint theory to systems with more
complicated river channel geometries. The STR package of MODFLOW assumes a wide, rectangular river
channel cross section, so the adjoint theory thus far has been developed for that case. An unfunded J.D.
student, Daniel McCarl, has begun working on the extension of the adjoint theory to more complicated
river channel geometries. After he completes his J.D. degree, he plans to pursue a Ph.D. in civil
engineering, and will continue work on this topic for that degree. Although he will not begin his Ph.D.
until after this grant expires, his work builds off of the adjoint theory developed under this grant.
Remaining Work
The following work remains to be completed, and is expected to be done during Summer 2013.
1. Completion of the San Pedro case study. Presently, the adjoint simulation results for the San
Pedro case study match the pattern of the forward simulation results, but do not match the
magnitude. Further investigation is needed to fix this inconsistency. Once it is completed, we
will prepare a manuscript on the topic for submission to Groundwater.
2. Development of software tools to automatically create input files for MODFLOW adjoint
simulations. We have written a Matlab code to take forward model MODFLOW input and output
files and create from them the adjoint model MODFLOW input files. The code was written for
our specific needs, and is not robust. We will write a robust Fortran code, building off of
MODFLOW subroutines that read in the input files, to create the adjoint model input files. I
have spoken to Mary Hill (USGS) about the possibility of including this code with the MODFLOW
distribution. If we were to do that, it would require rigorous testing that would extend beyond
Summer 2013. Regardless, guidance on adapting MODFLOW input files to be used for adjoint
simulations will be included in the Groundwater article on the San Pedro study.
3. Dissemination of results of the investigation of the effects of streambed hydraulic conductivity
on stream depletion. All of the work is completed on this part of the project. During Summer
2013, Gregory Lackey, the student working on this project, will complete his M.S. thesis and
prepare a journal article to submit on this work.
Students:
Gregory D. Lackey – M.S. student, started May 2012, expected completion is August 2013.
Daniel McCarl – J.D. student, started June 2012, unfunded.
Journal articles in review:
Griebling, S.A. and R.M. Neupauer, Adjoint modeling of stream depletion in groundwater-surface water
systems, Water Resources Research, originally submitted June 2012, revised and resubmitted
April 2013.

Conference proceedings papers (published or in press):
Griebling, S.A. and R.M. Neupauer, Adjoint Methodology to Simulate Stream Depletion due to Pumping
in a Non-linear Coupled Groundwater and Surface Water System, Computational Methods in
Water Resources, 2012a.
Lackey, G., R.M. Neupauer, and J. Pitlick, Effects of varying stream channel conductance on siting new
pumping wells in an aquifer, 2013 World Environmental and Water Resources Congress,
American Society of Civil Engineers, 2013a, in press.
Lackey, G., R.M. Neupauer, and J. Pitlick, Effects of spatial and temporal variations of streambed
hydraulic conductivity on stream depletion calculations, MODFLOW and More Conference,
2013b, in press.
Neupauer, R.M. and S.A. Griebling, Comparison of forward and adjoint approaches to calculate stream
depletion with application to the Upper San Pedro Basin, MODFLOW and More Conference,
2013, in press.
Conference presentations:
Griebling, S.A. and R.M. Neupauer, Comparison of forward and adjoint approaches of stream depletion
in the San Pedro River, Arizona, U.S.A., American Geophysical Union, Fall Meeting, 2012b.
Lackey, G.D., R.M. Neupauer, and J. Pitlick, Effects of riverbed conductance on stream depletion,
American Geophysical Union, Fall Meeting, 2012.
Lackey, G.D., R.M. Neupauer, and J. Pitlick, Varying Stream Channel Conductance and its Effects on
Stream Depletion Estimations, 8th Annual Hydrologic Sciences Student Symposium, University of
Colorado, Boulder, Colorado, March 2013c.

ater Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky Mountain West: Heavy Metals and Disinfection By

Water Quality Impacts of the Mountain Pine Beetle
Infestation in the Rocky Mountain West: Heavy Metals and
Disinfection Byproducts
Basic Information
Water Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky Mountain
West: Heavy Metals and Disinfection Byproducts
Project Number: 2011CO245G
Start Date: 9/1/2011
End Date: 8/31/2014
Funding Source: 104G
Congressional
D-CO7
District:
Research Category: Water Quality
Focus Category: Water Quality, Hydrogeochemistry, Treatment
Descriptors: None
Principal
John E. McCray, Reed Maxwell
Investigators:
Title:

Publications
1. McCray, John, 2011, Water Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky
Mountain West: Heavy Metals and Disinfection Byproducts, Colorado Water Institute Proposal, 38
pages.
2. McCray, John, 2011, Water Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky
Mountain West: Heavy Metals and Disinfection Byproducts, Colorado Water Institute Proposal, 38
pages.

Water Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky Mountain West: Heavy Metals
1
an

Water Quality Impacts of the Mountain Pine Beetle Infestation in the Rocky Mountain West: Heavy
Metals and Disinfection Byproducts
John E. McCray, Colorado School of Mines
The following report summarizes the work performed under Subaward Number G-2914-1; PI: Dr. John E.
McCray for the reporting period ending 18 March 2013.
1. Research: Project Synopsis
The goal of the research funded under this subaward, is to understand the potential for
disinfection byproduct formation and metal mobilization resulting from perturbations to the
water and nutrient cycles in forested watersheds currently experiencing a severe mountain pine
beetle epidemic (Figure 1). The subaward provides the means to add these analyses to the
existing USGS research project being conducted in Rocky Mountain National Park, under the
supervision of Dr. Dave Clow.
During this reporting period, the following tasks were completed: (a) Soil sampling and
sequential extractions were completed to identify differences in metal sources and mobility
beneath trees experiencing different phases of attack; (b) continued coordination and field
sampling with Dr. Clow (USGS) and his field team; (c) analysis of surface water samples (archived
by Dr. Clow and collected by Lindsay Bearup) for stable isotopes was completed; (d) initial
hydrologic flow path analysis was completed using the isotope data. The goal of the current
analyses is to understand whether metal availability and mobility is altered by the MPB
infestation and to investigate potential changes to stream water sources in RMNP using isotope
analysis. The goal for sample collection in the next field campaign is to continue to isolate the
effects of the MPB on the potential for disinfection byproduct formation and metal mobilization.
Specifically, it has become apparent that hydrologic flow paths may help explain the observed
discrepancy between increased metal mobility and carbon fluxes in the soils and relatively little
change in stream samples. As such, the main focus of our research over the next year is
intended to improve our understanding of the flow paths transporting carbon and metals to the
streams, and if the MPB is impacting water sources and residence times in these high mountain
systems.
2. Publications
The literature review co-authored by Lindsay A. Bearup during this reporting period and funded
by this subaward, directly contributed to the following review article, currently under review at
Biogeochemistry. In addition, two conference presentations by PhD student Lindsay Bearup
were published as abstracts. Finally, Professor McCray gave two invited talks (not published) in
the fall related to this project. The citations for these activities are provided below.
Mikkelson KM, Bearup LA, Maxwell RM, Stednick JD, McCray JE and Sharp JO. Bark beetle
infestation impacts on nutrient cycling, water quality and interdependent hydrological effects. In
review at Biogeochemistry.

Bearup, L.A., Maxwell, R.M., Clow, D.W., McCray, J.E., Sharp, J.O. Understanding changes to
interrelated hydrologic and trace metal cycles in mountain pine beetle infested
watersheds. Abstract GC23C-1081. 2012 Fall Meeting, AGU, San Francisco, Calif., 3-7 Dec, 2012.

1

Bearup, L.A., Mikkelson, K.M., Maxwell, R.M., McCray, J.E., Sharp, J.O. Understanding changes to
contaminant transport in mountain pine beetle infested watersheds. CUAHSI Colloquium,
Boulder, Colorado, 16-18, July 2012.
McCray, J.E., 2012. Impact of the mountain pine beetle epidemic on water resources and quality
in the Rocky Mountains, Presented at the Environmental Engineering Seminar Series,
Department of Civil and Environmental Engineering, University of California Berkeley, 30
November 2012.
McCray, J.E., 2012. Impact of the mountain pine beetle epidemic on hydrology and water quality
in the Rocky Mountains, Presented at the Environmental Engineering & Science Seminar Series,
Department of Civil & Environmental Engineering, Stanford University, 26 October 2012
3. Information Transfer Program
The research group participated (as experts) at a mountain pine beetle public education forum
at Denver Museum of Nature and Science on January 22, 2013. Also see journal papers and
public presentations listed above.
4. Student Support
This subaward provided funding for one PhD student during this reporting period.
5. Student Internship Program – N/A
6. Notable Achievements and Awards –
a. Literature review submitted and under review.
b. 2 conference abstracts published at national conferences
c. Professor McCray gave invited talks using material from this project in the Stanford
seminar series for Environmental Engineering Science, and at Cal-Berkeley for the Civil
and Environmental Engineering seminar series.
d. 2012 Field Season completed with soil and water samples collected for analysis.
e. Soil samples used for sequential extractions and metal mobility analysis.
f. Water samples (archived by Dr. Clow and collected by Lindsay Bearup) analyzed for
stable isotopes
g. Initial hydrologic flow path analysis based on isotope mixing models completed.

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Figure 1: MPB impacted forest above Grand Lake in Rocky Mountain National Park

Figure 2: PhD Student, Lindsay Bearup taking a stream sample for stable isotopes analysis in Rocky
Mountain National Park.

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and Drawbacks of Different Institutional Arrangements to Enhancing Forest and Water Ecosystem Services and Ecosystem

Assessing the Benefits and Drawbacks of Different
Institutional Arrangements to Enhancing Forest and Water
Ecosystem Services and Ecosystem Services Markest in
Colorado
Basic Information
Assessing the Benefits and Drawbacks of Different Institutional Arrangements to
Title: Enhancing Forest and Water Ecosystem Services and Ecosystem Services Markest in
Colorado
Project Number: 2012CO257B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional
4th
District:
Research
Social Sciences
Category:
Focus Category: Management and Planning, Water Quality, None
Descriptors: None
Principal
Antony Cheng
Investigators:

Publications
There are no publications.

Assessing the Benefits and Drawbacks of Different Institutional Arrangements to Enhancing Forest 1and Wat

Assessing the Benefits and Drawbacks of Different Institutional Arrangements to Enhancing Forest and
Water Ecosystem Services and Ecosystem Services Markets in Colorado
Heidi Huber-Stearns, PhD Student, Department of Forest and Rangeland Stewardship, Colorado State
University
Faculty Advisors: Antony Cheng and Joshua Goldstein
Introduction
The forested watersheds of the western U.S. are critical to the supply of clean drinking water to myriad
downstream users, including agriculture and urban population centers. Intensifying watershed risks,
inadequate public and private funding, loss of land stewardship capacities, and limitations of existing
policies are all converging on the matrix of state, federal and private lands across the region. These
challenges, combined with opportunities arising from expanding cross-sector collaborations, provide a
fitting context for the development of programs that incentivize the stewardship of public
environmental resources across land types. Such incentive programs are geared toward linking
ecosystem service providers (e.g., landowners or a federal agency improving water quality or quantity
upstream) with those who depend on those services (e.g., downstream utilities, breweries). Incentivebased programs targeting watershed ecosystem services, often broadly classified as Payments for
Watershed Services (PWS), have expanded rapidly in the western U.S. over the last decade. PWS is a
policy tool that can be used in order to address environmental issues of concern, such as water supply
and security. While relevant reports have highlighted many of these programs, until now, no
comprehensive report existed that detailed characteristics for all PWS programs in the western U.S. As
these programs continue to expand, a window of opportunity exists to use lessons learned from these
programs to shape future design and implementation of new programs, and also to improve the
effectiveness of existing programs.
Study Area
Our study region included the western U.S., encompassing: Arizona, California, Colorado, Idaho,
Montana, New Mexico, Nevada, Oregon, Utah, Washington, and Wyoming. The western U.S. provides
an appropriate study site for this project, due both to the sheer number of PWS-type programs
emerging across the region, as well as the increasing watershed and natural resource concerns, such as
wildfire risk and effects, overall forest health, source water protection, and increasing water quality
regulations.
Research Objectives
The purpose of our investigation was to characterize PWS programs in the western U.S. region by
understanding: 1) the key design elements of these programs, and 2) how experimentation on-theground relates to and differs from what we know of PWS literature and related theory.
Methods
We began our project with a literature and document review in order to generate an informed
understanding of existing documentation of PWS programs in the west, as well as to identify which
program attributes we should include in documenting programs. To inform our approach, we used
sources such as Ecosystem Marketplace's 2010 State of Watershed Payments report and Watershed

Connect Web-platform, as well as Carpe Diem West and EcoAgriculture reports, all of which identified a
varying number and type of PWS programs in the region.
Survey Development and Data Analysis
For survey design and administration, we partnered with Ecosystem Marketplace, an online source of
news, data, and analytics on ecosystem services projects around the globe (see
www.ecosystemmarketplace.com/). Our survey was administered online to all identified relevant
programs in the study area. Survey follow-up was conducted by phone. We conducted quantitative data
analysis in SPSS (“Statistical Package for the Social Sciences” from IBM) with the resulting survey data.
Results
We found 41 programs in operation, 14 programs in design, and 12 programs that were either inactive
or did not have data to report. In this section, findings are reported for only the 41 programs identified
as currently in operation since the programs in development do not yet have complete data.
Overall Program Characteristics
Geographically, the number of programs varied by state, with at least one program in each state. The
highest concentration of programs was found in the Pacific Northwest (Oregon and Washington). The
programs ranged in age, with the oldest programs (n = 9) established in 1970-80s. In the past decade,
the number of operating programs doubled, reaching 41 programs in 2012. The majority of programs
(88 percent) include private land. By comparison, approximately 35 percent of programs include (mainly
federally managed) land.
Our results demonstrate that a variety of actors are involved in these programs, including, for example,
states (Water Resources, Ecology, Forestry, Fish and Wildlife departments) and water utilities as
ecosystem services buyers, NGOs as program administrators (those managing program funds), and
private landowners and federal agencies as sellers. The collaborative nature of these arrangements is
evident from the number and differing sectors of participants. Most programs involved voluntary
participation on the part of ecosystem-service sellers, but contained some regulatory driver(s) for those
participating as buyers. Drivers for the programs stemmed mainly from meeting state and federal
regulations, including state-specific propositions and statutes, particularly instream flow requirements.
Other federal regulatory drivers include the Clean Water Act and Endangered Species Act. Seventy-six
percent of programs focused on water quality ecosystem services, including a subset of programs (20
percent) that focused on phosphorous and/or nitrogen specifically. Seventy percent of the programs
concentrated on flow restoration ecosystem services, which demonstrates that many programs were
aimed at dual water quality and quantity goals. Programs were found to conduct different management
actions in order to achieve targeted ecosystem services. Most programs (66 percent) employed water
rights transactions, including acquisition of temporary leases and permanent water rights transfers.
Several programs (27-34 percent) also used restoration and protection actions to achieve program goals.
Other program actions included reforestation, alterations to agricultural and operational procedures,
and fire suppression.
Mapping Project Results
In collaboration with the Geospatial Centroid at Colorado State University, we are in the process of using
the survey data and results to organize and distribute spatial data and map products. This portion of our

project contains three products: 1) a map for publication, 2) a spatial database, and 3) an initial Web
map. The map for publication purposes displays the programs and their respective watersheds within
the study region (Figure 1). The development of a spatial database includes detailing the spatial extent
of each watershed project and attributes of each program, such as the previously described program
characteristics. For the final product, the Centroid will publish the data (from the developed database)
as a Web map service and will create a website where the data can be viewed. The anticipated
completion date for the spatial database and web map service is April 30, 2013.
Conclusion/Implications
As is evidenced by the substantial increase in programs implemented across the landscape, and the
programs in design at the moment, it is clear that these types of PWS programs are continuing to grow
in our region. It is important to understand how to appropriately design programs, which actors to
target as potential participants, and the types of social-ecological contexts and drivers for which this
type of policy tool is suitable. Another finding from our data analysis is the identification of differences
between programs, dividing our dataset into subgroups. Some key differences between programs
include geographic distinctions, management actions, types of sellers, and program objectives. For
example, in the Pacific Northwest, many programs are focused on increasing instream flow in rivers
through water rights and leases from individual private landowners. In the more arid parts of the west
(e.g., Colorado, New Mexico, Arizona), programs are focused on protecting watershed health and
reducing wildfire risk by employing restoration and protection actions, typically on public land (e.g.,
National Forest System lands managed by the U.S. Forest Service). We are currently further developing
these program typologies using survey results. These distinctions can expand both practitioner and
academic awareness of the differences and similarities between programs, thus generating a more
mutual understanding of the types of programs, as well as where and how they operate. Understanding
what and how actors, policies, and communication influence the design, implementation, and outcomes
of these projects across the landscape is essential to providing lessons learned for future program
design.
Acknowledgements
We would like to thank the Colorado Water Institute (CWI) for sponsoring survey and mapping
development for this project. This support allowed us to speed up the development and administration
of our survey through funding research hours and encouraged the development of new collaborations
with external partners. CWI funding also provided us the opportunity to work with the Geospatial
Centroid to develop maps and related products. We thank the CSU Colorado Agricultural Experiment
Station for its support of our larger research project. We also thank other project collaborators
including, Genevieve Bennett and the Ecosystem Marketplace team, and AES project collaborator Ted
Toombs.

Figure 1. Incentive-based Watershed Programs in the Western United States

Structural and Functional Controls of Tree Transpiration in Front Range Urban Forests

Structural and Functional Controls of Tree Transpiration in
Front Range Urban Forests
Basic Information
Structural and Functional Controls of Tree Transpiration in Front Range Urban
Forests
Project Number: 2012CO260B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional District: 4th
Research Category: Climate and Hydrologic Processes
Focus Category: Water Use, Climatological Processes, Economics
Descriptors: None
Principal
David Cooper
Investigators:
Title:

Publications
There are no publications.

Structural and Functional Controls of Tree Transpiration in Front Range Urban Forests

1

Structural and Functional Controls of Tree Transpiration in Front Range Urban Forests
Edward Gage, PhD Candidate, Ecology, Department of Forest and Rangeland Stewardship, Colorado
State University
Faculty Advisor: David J. Cooper
Introduction
A few basic land cover (LC) classes dominate the urban landscape, but just as a painter can coax
varied hues from a few primary colors, basic LC types such as trees, turfgrass, and pavement are
arranged in complex patterns in cities. The abundance and spatial arrangement of LC classes forms a
city’s physical structure, which, in contrast to natural ecosystems, is largely the product of human
agency. Socioeconomic, demographic, and land-use factors (e.g., zoning regulations) contribute to a
city’s legal and social structure. Combined, these shape a city’s basic character and influence
phenomena important to water managers, such as evapotranspiration (ET) and residential water
demand.
Vegetation, especially trees, strongly influences urban structure and function. Front Range cities are
built largely on native grasslands, and on the pre-settlement landscape, trees were generally
restricted to riparian areas. An LC change commonly accompanying urbanization is the
establishment of irrigation-dependent vegetation types. Water applied to support these
communities often accounts for the majority of summer water demand, so an improved
understanding of factors influencing plant water requirements and outdoor watering behavior is
critically important to water management.
The urban forest is particularly varied, supporting trees differing in age, size, and basic functional
characteristics. For example, transpiration rates and stomatal sensitivity to atmospheric drivers of ET
vary among species and functional groups, due to differences in plant physiology, xylem anatomy,
root distribution, and phenology. If functional differences can be generalized and inferences made to
landscape-scale distribution patterns, a truer accounting of vegetation's role in urban
ecohydrological processes may be possible.
Research Questions
Our broad research objective is to explore landscape-scale spatial variation in vegetation
characteristics potentially important as drivers of outdoor water consumption in a typical Front
Range urban area. Our motivation is to develop information applicable to studies of the urban water
balance and outdoor residential water demand. Specifically, we ask:
•
•
•

What socioeconomic, demographic, and historical land-use history variables best predict
measures of urban vegetation structure and composition?
Does the compositional diversity of trees in the urban forest vary in relation to broader LC
patterns and social structure?
Can tree compositional diversity be reduced meaningfully by identifying functional types?

Methods
Land Cover Mapping and Landscape Analysis
At the broadest scale, we used remote sensing analyses to map and characterize LC characteristics
for our Aurora, Colorado study area (Figure 1). Accurate LC data of sufficiently fine grain is a

prerequisite for analyses in urban areas. Existing LC data are too course to be used for parcel-scale
analyses, so we developed our own dataset using an object-oriented segmentation and random
forest classification approach on primary and derived high spatial resolution (0.5 m GSD)
multispectral imagery and lidar layers. Lidar is an active remote sensing technology similar in
principle to radar that uses pulsed laser light instead of microwaves to produce point clouds
characterizing the 3-D structure of what is being sensed. Six classes were mapped: trees, buildings,
low vegetation, low impervious, bare soil, and water (Figure 2).
We calculated the proportional area of each LC class, as well as various image and lidar-derived
structural variables (e.g., mean tree height, NDVI, etc.), for study area parcels, census blocks, and
census block groups using zonal statistics tools in ArcGIS. A similar procedure was used with socioeconomic, demographic, and historical land-use data from the 2010 U.S. Census, Arapahoe County
Assessor’s Office, and the U.S. Geological Survey. Agglomerative cluster analysis was used define
natural groupings of sampling units at a given scale and to provide a means of identifying portions of
the landscape exhibiting similar structure.
Models predicting structure variables were then constructed in the R statistical program, with
separate analyses constructed for parcel, block level, and block group level units. We used Random
Forests, an ensemble method commonly used in data mining because of its predictive accuracy and
ability to work with highly dimensional and nonlinear data. Variable importance plots were used to
identify variables most useful for prediction.
Analysis of Urban Tree Composition and Functional Variation
Our LC data are precise enough to effectively discriminate among broad LC classes. However, the
data sets we used contain insufficient information from which to discriminate individual tree species,
so we used a tree inventory layer provided by Aurora. These data were used to evaluate spatial
distribution patterns and assess the relative abundance of tree functional types defined by wood
xylem anatomy (e.g., conifers, diffuse-porous and ring-porous angiosperms), a factor shown in
previous studies to influence ecohydrological function.
Most studies documenting ecohydrological consequences of xylem anatomy have been conducted
outside of the Front Range. To evaluate whether previous findings apply to the tree species and
environmental conditions here in Colorado, we measured tree transpiration using thermal
dissipation sap flow sensors at five Aurora parks. Data are still being analyzed, but will help quantify
differences in tree transpiration rates among species with different physiological characteristics. Our
intent isn’t to directly scale-up field-based transpiration to the study area—there are too many
confounding and unmeasured variables; rather, data will be used to contextualize landscape-scale
tree distribution patterns and evaluate the utility of incorporating tree functional type into future
sampling and modeling.
Results
Our land cover maps reveal complex spatial patterns across our study area. The relative abundance
of different land cover classes varies dramatically depending on land use and zoning parameters. For
example, the highest impervious cover is found in commercial settings, while vegetation cover is
greatest in city owned parks, open space, and golf courses. Residential areas generally show
intermediate characteristics between those found in commercial and park settings.
Total tree cover and the proportional share of vegetation cover from trees is greatest in the
Northwestern portion of the assessment area, and is directly related to the age of the neighborhood
(Figure 3; panels A and B). Tree height and canopy volume layers are correlated with each other and
with absolute tree cover, showing similar spatial trends over the assessment area, with the greatest
mean and maximum height and volume seen in older portions of the city.

Tree inventory analyses reveal additional complexity in the urban forest. Of the 48,957 trees in the
assessment area, 51.8 percent were classified as diffuse-porous, 41.3 percent as ring-porous, and 6.8
percent as conifer (Figure 3). Our sap flow measurements reveal significant tree to tree variability in
transpiration. Some is due to micro-site and size variation among trees, but data also suggest
differences among trees with different wood anatomy.

Discussion
Our research highlights the complexity of urban land cover patterns, particularly with regard to
vegetation. Results suggest numerous socio-economic variables are correlated with physical
structure characteristics (e.g., percent tree cover, mean tree height, etc.), a finding consistent with
previous research. Our LC classification captures broad differences in LC, but fails to discriminate
among tree types. Traditional tree inventories complement data from remote sensing analyses by
providing species and functional type-specific information. Preliminary results from sap flow
analyses support the notion documented elsewhere that tree functional types respond differently to
climatic drivers of ET.
Individually, the different scales of analysis provide interesting insights on urban land cover patterns
of direct importance to water managers. In future analyses, we will work to elucidate controls on
these patterns, and importantly, link patterns and processes across varying scales. Results also
suggest that time since development is an important conditioning factor shaping vegetation
structure, but more work is needed to understand how temporal changes in structure affects urban
microclimate, water and energy demand, and ecological services.

Figure 1. Map of Aurora, Colorado study area.

Figure 2. Flowchart illustrating main steps in development and analysis of land cover data (panel A); example
of land cover product (panel B) for an Aurora Park also used in field measurements of tree sap flow (inset box,
panel B; panel C).

Figure 3. Clockwise from the top left: parcel level maximum tree height for an older neighborhood built in the
early 1960s (panel A); maximum tree height in a newer neighborhood constructed in the early 2000’s (panel
B); dendrogram illustrating clustering of census blocks based on agglomerative cluster analysis of physical
structure variables (panel C); box plot of mean census block Normalized Difference Vegetation Index (NDVI)
clusters (panel D); intermediate-scale map illustrating the proportion of all trees in individual census blocks
with ring-porous xylem anatomy (panel E); Andrew Carlson, CSU Research Associate, collecting tree core from
green ash tree outfitted with sap flow sensor (panel F).

Winter Precipitation Variability in the Colorado Rocky Mountains

Winter Precipitation Variability in the Colorado Rocky
Mountains
Basic Information
Title: Winter Precipitation Variability in the Colorado Rocky Mountains
Project Number: 2012CO261B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional District: 4th
Research Category: Climate and Hydrologic Processes
Focus Category: Climatological Processes, Models, Water Quality
Descriptors: None
Principal Investigators: Nolan Doesken

Publications
There are no publications.

Winter Precipitation Variability in the Colorado Rocky Mountains

1

Winter Precipitation Variability in the Colorado Rocky Mountains
Andrew Muniz, Student, Earth Science: Meteorology, University of Northern Colorado
Faculty Advisor: Nolan Doesken
Introduction
Skillful snowpack, streamflow, and water supply prediction with reasonable lead times is essential to
water management and planning not only in Colorado, but around the U.S. With drought so widespread
and severe in 2012, the interest in snowpack and streamflow prediction is at an all time high in Colorado
for municipal water management, agriculture, and outdoor recreation.
The Rocky Mountains of Colorado receive a majority of their annual precipitation during the winter
season, mostly as snow. The snowfall that has accumulated at elevations above 9,000 feet by mid-April
each year becomes the source of most of the growing season’s runoff and water supplies. This
exemplifies the need and opportunity to improve forecast models to assist water management officials.
Climate teleconnections are one tool used in seasonal predictions around the world. The El Niño
Southern Oscillation (ENSO) has been the most popular climate predictor here in Colorado, in terms of
seasonal snowpack variability. For the purpose of this study, ENSO, North Atlantic Oscillation (NAO), and
Pacific Decadal Oscillation (PDO) will be used in combination to identify correlations with snowpack and
streamflow and to attempt to improve seasonal water supply forecasts.
Research Objectives
Many studies have been conducted investigating seasonal patterns and year to year variations in the
magnitude and timing of precipitation in the Rocky Mountain region and relating these to streamflow
discharge in Colorado’s major river basins. The relationship of these variations to the phase of ENSO and
other modes of large scale atmospheric and oceanic circulations indicates some potential for skill in
streamflow forecasting. Analyses of Colorado precipitation data, especially winter season precipitation,
reveal that there are many years where precipitation anomalies (wet versus dry) appear out of phase
between the northern and southern mountains of Colorado. The objective for this research is to better
recognize characteristic latitudinal precipitation patterns and document their association with large
scale climate indexes such as ENSO, NAO, and PDO. The end result of this project is to develop a model
with more skill in forecasting snowpack and runoff to further assist water management officials.
Methods
In order to document the impact each teleconnection has in Colorado, snowpack and streamflow data
from diverse geographic regions of Colorado were selected. We first obtained snowpack data from 49
individual locations provided by the Natural Resources Conservation Service (NRCS), each of which has
snow water equivalent, or SWE, readings dating back to 1950 or earlier. The 49 locations were
separated into 11 mountainous regions throughout the state, based on geographic location and similar
year to year variations in SWE. Then, one site from each of the 11 regions was selected to represent
each region, which was solely based upon similar elevation. April 1 SWE data were selected since this is
close to the maximum seasonal snowpack water content and is best correlated with subsequent runoff
and streamflow volumes. These 11 locations, Figure 1, represent spatial differences in snowpack in
Colorado from the original 49.

Seventeen streamflow gauge sites were then chosen from the United States Geological Survey (USGS)
and the Colorado Division of Water Resources (CDWR). A total of nine of the overall 17 stream gauge
locations are naturalized streamflow sites, meaning not influenced by human activity. We only wanted
to use naturalized sites, but not enough were readily available with close proximity to each SNOTEL
location. This is why eight of the total 17 gauge sites are not naturalized sites. Streamflow discharge for
these 17 sites was totaled from April 1 – July 31 and measured in cubic feet per second. It was then
compared against snowpack from nearby SNOTEL stations to confirm how well correlated snowpack is
with runoff in various regions across the state (Table 1).
Lastly, ENSO, NAO, and PDO monthly index values were obtained from the Climate Prediction Center
and National Climatic Data Center, each of which dated back to 1950. A monthly time series of each
index value was obtained starting at the beginning of each water year. (October – March, Figure 2) Also,
a yearly time series beginning at the point of which recording of the stream gauge began until 2012
(Figure 3).
Results
Data provided for each of the preceding six monthly climate indices was correlated with seasonal (AprilJuly) streamflow for that year using Statistical Analysis System, or SAS, and independently verified with
Microsoft Excel. Streamflow versus SWE correlation show differences (Table 1) for a multitude of
reasons that cannot fully be explained by climate forcings. However, most of the sites are well
correlated and explain one another. The month with the highest correlation for each climate index was
identified. Then the index values best correlated with streamflow were combined using multiple
regression to provide a model to determine how well the three best single month correlations
compared with the observed streamflow discharge values.
The results are shown in Table 1. Correlations are generally weak, even for ENSO. However, there is just
enough correlation with several month lead time to possibly provide some useful predictive skill.
Interestingly, for most regions the NAO showed better correlation than ENSO. The NAO was more highly
correlated during the month of November (13) than all other months combined (four) and the PDO was
more highly correlated during March (14) than all other months combined (three).
Based on the results in this study, it can be concluded that for the period of the years tested, ENSO is
ultimately the weakest climate predictor with NAO and PDO performing better. Since many forecasters
have relied more on ENSO when making their upcoming winter snowpack predictions, using a model
equipped with NAO and PDO may improve forecast accuracy. To show this, (Table 2) illustrates how
many times a specific climate index is the best, worst, and average predictor, based on the R2 value.
Future research for this project is to construct a full scale model, of which will include observed yearly
discharge rates from April 1 – July 31 and compare it to each monthly climate index from October
through March on a year to year basis. So this full model will include all six months from each climate
index and total to 18 variables as compared to only three used previously. This may improve streamflow
forecasts in the future and better assist water management officials in decision making. Lastly, we would
like to show our forecasted values for each streamflow location based on our best three month
correlation model (Table 3).
Acknowledgements

We would both like to thank the Colorado Water Institute and Colorado State University for funding this
research.

ting a Water Balance for the San Luis Valley: Streamflow Variability, Change, and Extremes in a Snowmelt Dominated Inter

Reconstructing a Water Balance for the San Luis Valley:
Streamflow Variability, Change, and Extremes in a
Snowmelt Dominated Internal Drainage Basin
Basic Information
Reconstructing a Water Balance for the San Luis Valley: Streamflow Variability,
Change, and Extremes in a Snowmelt Dominated Internal Drainage Basin
Project Number: 2012CO262B
Start Date: 3/1/2012
End Date: 8/31/2013
Funding Source: 104B
Congressional
4th
District:
Research
Climate and Hydrologic Processes
Category:
Focus Category: Irrigation, Surface Water, None
Descriptors:
Principal
Steven Fassnacht
Investigators:
Title:

Publications
There are no publications.

Reconstructing a Water Balance for the San Luis Valley: Streamflow Variability, Change, and Extremes
1
in a

Reconstructing a Water Balance for the San Luis Valley: Streamflow Variability, Change, and Extremes
in a Snowmelt Dominated Internal Drainage Basin
Niah Venable, PhD Student, Watershed Science, Colorado State University
Faculty Advisor: Steven Fassnacht
This report summarizes work to date on the CWI/NIWR State Program Project Award 2012CO262B. The
project PI is Dr. Steven Fassnacht, Associate Professor of Snow Hydrology, and the student researcher is
Niah Venable, a PhD student in the Watershed Science program at Colorado State University. The
project originally began on March 1, 2012, with a completion date of March 1, 2013, but due to ACMS
field research fellowship duties in Mongolia and fall semester GEOL 122 instructor commitments for
Venable, the completion date was extended to August 1, 2013.
Research Project Objectives:
•

Assess the natural variability, extremes, and changes in streamflow to examine how natural
systems in a closed basin function over longer periods and provide insight into the sustainability
and further development of dry regions and to help define possible impacts of future change.

•

Compare a modern water balance and streamflow of a catchment draining into the basin with
that reconstructed from paleo-climatic data derived from tree-rings.

Tasks Completed:
•

Preliminary project work was initiated in Fall of 2012. Additional references and data sources
were identified and the research plan for the first half of the project was finalized.

•

In the Spring semester of 2013, tree-ring records from the International Tree-Ring Data Bank
(ITRDB) were screened for suitability and 9 sites within about 100 km of Crestone Creek in the
San Luis Valley were selected for analysis.

•

The residual site chronologies were used as potential predictors of streamflow over a period 300
years longer than the observed flow record at that creek. Stepwise regression was used to
develop the model. Three chronologies located to the south and east of the watershed and
extending from years 1636 to 2000 provided a best fit to the streamflow record, with a final
model R2 of 0.69. Other statistical tests also confirmed the robust nature of the reconstruction.

•

The results of the analysis compare favorably to previous analyses performed by Woodhouse et
al., (2004). Her reconstructions of flow in Saguache Creek, and the Rio Grande at Del Norte,
both in the San Luis Valley show similar trends in wet and dry conditions and have similar
statistical results and model fits.

Student Support:
This award provided support for the PhD student Venable, and will continue to provide critical support
for her to complete project work over the next few months.

Publications:
Venable, N. B. H., Brown, P.M., Fassnacht, S. R., “Streamflow to Nowhere: Long-term Variability of Flow
Into the San Luis Closed Basin, CO, USA.”Poster Presentation, 33rd Annual American Geophysical Union
Hydrology Days, Colorado State University, Fort Collins, CO, March 27th, 2013.
Talk prepared for the Spring Geosciences Advisory Council Student Presentations which were postponed
to the Fall semester 2013 due to poor weather conditions and other departmental schedule changes.
Remaining Work Plan (subject to revision):
•

Further examine flow regimes, extremes and long-term variability at Crestone Creek via
completed flow reconstruction(s).

•

Better characterize Crestone Creek area through field investigations of flow conditions, land
use/land cover, etc.

•

Analyze data and create modern water balance (Thornthwaite model) using PRISM inputs and
observed flow (WY 1948-2012).

•

Reconstruct precipitation for Crestone watershed using stepwise regression process on original
pool of tree-ring chronologies. PRISM data will be used for calibration of the model.

•

Examine feasibility/create a paleo-water balance using reconstructed precipitation and possibly
temperatures (NOAA/ITRDB products).

•

Compare results to other modeling efforts and basin analyses as appropriate.

Project Timeline (details subject to revision):
•
•
•
•
•
•
•
•

Fieldwork, May 10th-13th, 2013.
Modern water balance modeling, May 22nd-25th.
Precipitation reconstruction, May 27th-May 31st.
Paleo- water balance modeling, June 1st-6th.
Reporting draft, June 9th-11th.
Meet with Fassnacht to discuss draft and further project work, June 12th-14th.
Final project report (draft), July 1st. Submission to CWI soon after?!
Further incorporation of additional project work and results to conference
proceedings/papers/dissertation proposal through end of 2013.

Reference: Woodhouse, C.A., et al. (2004) TreeFlow Colorado Streamflow Reconstructions. IGBP
PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2004-029. NOAA/NGDC
Paleoclimatology Program, Boulder CO, URL http://treeflow.info/index.html

The Short and Long-Term Impacts of Drought on the Structure of Regional Economics: Investigating the Farm Supply C

The Short and Long-Term Impacts of Drought on the
Structure of Regional Economics: Investigating the Farm
Supply Chain
Basic Information
The Short and Long-Term Impacts of Drought on the Structure of Regional
Economics: Investigating the Farm Supply Chain
Project Number: 2012CO263B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional
4th
District:
Research Category: Social Sciences
Focus Category: Drought, Economics, Methods
Descriptors: None
Principal
Christopher Goemans
Investigators:
Title:

Publications
There are no publications.

The Short and Long-Term Impacts of Drought on the Structure of Regional Economics: Investigating
1 the Far

The Short and Long-Term Impacts of Drought on the Structure of Regional Economics: Investigating
the Farm Supply Chain
Ron Nelson, Master’s Candidate, Department of Agricultural and Resource Economics, Colorado State
University
Faculty Advisors: Christopher Goemans and James Pritchett
For the last two years, agricultural producers in Colorado have been faced with severe drought
conditions, resulting in significant economic losses. The drought has led to widespread crop failures,
damaged rangelands, and drastically reduced crop yields and livestock productivity. The financial
impacts caused by the drought will be felt by agricultural producers for years to come and may threaten
the long-term economic viability of some agricultural operations. Given forward and backward linkages
with other industries in the supply chain, the impact of drought typically extends well beyond those
sectors and communities immediately impacted. Federal and state agencies have responded to the
drought by offering millions of dollars in emergency drought relief. With a changing climate, likely
leading to an increased probability of extreme and recurring droughts, it is becoming an ever more
important policy concern to determine the effect that drought has on the resiliency of farmers and
ranchers.
The resiliency of farmers and ranchers is the ability of the agricultural producer to return to a similar
state of production after they have endured a stressor such as a drought. Understanding the factors that
influence the resiliency of agricultural producers is important for multiple reasons. First, understanding
existing levels of resiliency can convey how adaptable agricultural producers are to extreme and
changing climatic conditions. Second, it indicates how long farmers and ranchers can endure an
environmental stressor such as drought until they are ultimately forced to exit the agricultural sector.
Third, by understanding the determinants of resiliency, decision makers can design policies that help
agricultural producers adapt to the challenges presented by natural hazards such as drought. Fourth,
because farmers and ranchers are key components of rural communities, their resiliency is directly
correlated with the resiliency of rural communities. Lastly, small and mid-sized farms and ranches have
been found to be less resilient than large farms, which many believe decreases the adaptability of the
domestic food sector and may lead to food security concerns in the future. Therefore, by determining
the characteristics that influence resiliency, we can help improve food security. By investigating
resiliency, we aim to provide insight into the efficacy of the current drought relief policies and identify
ways to minimize the economic impacts felt by agricultural producers and regional economies.
Past studies that have examined resiliency indicate that there are multiple producer and enterprise
characteristics that influence the ability to adapt to drought and the producer’s decision to exit the
agricultural sector. Characteristics that have been found to influence farm exit include off-farm income,
the size of the operation, experience, and age. Characteristics related to drought induced exits include
decreased crop yields, number of acres fallowed, the duration of drought, access to irrigation, and
decreased profit. Most recently, a theoretical model was developed that suggested proxies for a
farmer’s or rancher’s overall wealth, such as groundwater, since it can be thought of as a savings
account during drought.

Our study explores the determinants of resiliency, but mainly focuses on the roles that wealth and the
duration of drought have on farmer and rancher resiliency. To investigate resiliency, we developed an
online survey that was administered to agricultural producers throughout Colorado. The survey inquired
about the circumstances faced during the 2012 drought and collected information on the characteristics
of producers and their production enterprise(s). As a measure of wealth, we inquired about the
respondent’s debt-to-asset ratio before and after the 2012 drought. Debt-to-asset ratio is defined as a
producer’s total liabilities divided by their total assets. And as a measure of resiliency, we asked
respondents what the probability was of them leaving farming/ranching if the drought continued for
another year. Respondents included all major producer types, and the sample was thought to be
representative of the larger agricultural enterprises in Colorado.
Using the data from the survey, we use regression analysis to estimate the determinants of resiliency
(see Table 1 for complete results). Several key findings emerge from the analysis. First, the analysis
suggests location is an important determinant of resiliency. Specifically, we found that the southeastern
region of Colorado was more resilient than other regions of Colorado (see Figure 1). This finding is
interesting partly because the Southeast region is in its second year of drought while most other regions
of Colorado are in their first. The increased resiliency that the region possesses during drought may be
due to the fact that the Southeast has a long history of drought and therefore has successfully adapted.
This may indicate that the duration of the drought may not be as important as where the drought is
occurring and if that area has been repeatedly exposed to similar droughts. A policy implication of this
finding is that drought assistance in form of educational outreach and financial resources may be better
utilized by regions less familiar with adapting and planning for drought.
Table 1: Regression Results
Dependent Variable
Resiliency

Definition
the respondent’s stated probability of leaving farming
in the next five years if drought continues in 2013

Independent
Variables
ln(acres)
Debt-to-asset ratio
Profit
(Debt-to-asset
ratio)*(Profit)
Southeast
Irrigation

Definition

Off Farm Income
Experience

the natural log of the number of acres in an operation
the debt-to-asset ratio after the 2012 drought
profit in 2012
interaction variable
the Southeast district of Colorado as defined by NASS
the type of enterprise divided into those with water and
those without
the percentage of income that comes from off of the
farm
the number of years the respondent has farmed and/or
ranched

Marginal
Effect
-0.0009
0.0054**
-0.0008
-0.0001

PValue
0.955
0.036
0.723
0.44

-0.1709***
0.0525

0.007
0.436

-0.0008

0.426

0.0011

0.594

Additionally, our analysis indicates that debt-to-asset ratio is a key determinant of the resiliency of a
farmer or rancher. As a proxy for the wealth of the farmer or rancher, this variable reflects, in aggregate,
how the farm or ranch has been financially managed over a long period of time. Debt-to-asset ratio’s
importance reveals that a one year drought may not be a significant factor in motivating an agricultural
producer to exit the sector, since it likely will not decrease drastically in a single year. Furthermore,
profit from the year 2012 was not found to influence resiliency, which furthers the claim that a one year
drought may not be impacting resiliency. However, multi-year droughts will surely increase the debt-toasset ratio of most agricultural producers, decreasing resiliency and possibly increasing agricultural
sector exits. This finding has implications for policy makers, agricultural producers, and industry. First,
producers and insurers need to be educated on how increasing debt can lower the resiliency of
agricultural producers, and how preparing financially for drought may increase the vitality of a
producer’s enterprise. Second, the form of assistance currently offered, low interest emergency loans,
may be decreasing farmer and rancher resiliency by increasing their debt-to-asset ratio. However, low
interest emergency loans may be minimizing the negative impact felt by agricultural producers and their
communities, and could be the best policy option available for the circumstances. To further determine
whether or not low interest emergency loans are the best option for drought assistance, additional
research could compare the exit rates of those farmers that choose to take low interest emergency
loans versus those that do not.

Figure 1: National Ag
Statistics Service—Colorado
Agricultural Statistics
Districts. Source: NASS, 2012

Quantifying Risks Producers Face when Entering Agricultural Water Lease Contracts

Quantifying Risks Producers Face when Entering
Agricultural Water Lease Contracts
Basic Information
Quantifying Risks Producers Face when Entering Agricultural Water Lease
Contracts
Project Number: 2012CO264B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional District: 4th
Research Category: Engineering
Focus Category: Management and Planning, Economics, Models
Descriptors: None
Principal
Christopher Goemans, James Pritchett
Investigators:
Title:

Publications
There are no publications.

Quantifying Risks Producers Face when Entering Agricultural Water Lease Contracts

1

Quantifying Risks Producers Face when Entering Agricultural Water Lease Contracts
Larisa Serbina, Department of Agriculture and Resource Economics, Colorado State University
Faculty Advisor: Christopher Goemans
Overview
Driven primarily by population growth along the Front Range, municipal and industrial (M&I) demand
for water in Colorado is expected to nearly double by 2050. Throughout most of Colorado, water is
already fully allocated—the majority of water being diverted for agricultural uses. These two factors
make it likely that the gap between existing M&I supplies and future demands will be met, at least in
part, by reallocating water out of agriculture. The Colorado Water Conservation Board’s (CWCB) 2010
State Water Supply Initiative (SWSI) forecasts that as much as 20 percent of existing irrigated land,
statewide, will be dried up due to meeting future urban demands. Growing concerns surrounding the
impacts to rural communities associated with the permanent dry up of agricultural land have led many
to advocate for alternatives to permanent transfers of water rights.
Water banks, interruptible water supply agreements, and multi-year leases are examples of such
alternatives that when combined with rotational fallowing and/or alternative cropping patterns are
thought to be less impactful on rural communities, while freeing up water to meet future needs.
Regardless of the nature of the agreement, each requires the producer to make changes in their
production practices to free up water. While identifying the optimal strategy is relatively easy to do after
the fact, uncertainty in output prices and potential yields significantly complicates the decision process.
Understanding the potential impacts apriori, both in terms of their impacts on expected profits and
variation in profits, is critical not only for policy makers trying to understand the potential viability of
such alternatives, but also for producers evaluating the potential efficacy of their choices. This research
develops both a conceptual and analytic framework for evaluating alternative cropping systems that
producers may choose when seeking to conserve water and compares them to baseline cases
corresponding to existing irrigated cropping systems. The goal is to develop a tool for irrigators and
policy makers that will allow them to evaluate the impact of various alternative cropping and rotational
fallowing strategies on the distribution of future profits accounting for uncertainty in yields and output
prices. While the tool can be applied anywhere, we illustrate its potential usefulness below with an
example focused on Weld county of Colorado.
Methodology
The focus of analysis is an irrigated farm manager’s question: how does the underlying distribution of
farm profits change when adopting a water conserving cropping system? The Excel model developed
evaluates the financial tradeoffs that exist when adopting different cropping systems under uncertain
price and yield conditions.
These financial tradeoffs include differences in realized profits, the potential for losses when price
and/or yields are low and the opportunity cost of unrealized financial gains.
Within the model, profits stemming from a “baseline” cropping pattern (e.g., 100 percent corn) are
calculated and compared to those associated with user-specified, alternative systems (e.g, 50 percent
corn, 50 percent fallow) that result in a given amount of conserved, consumptive water use (CU). Of key
importance is the recognition that any particular comparison represents a potential outcome given

assumed prices and yields. To represent the uncertainty faced by irrigators, the comparison is repeated
500 times under different output price and yield conditions, the suite of results providing a distribution
of outcomes under alternative conditions.
Figure 1 provides an illustration of the iterative process used. For each iteration, total profits are
calculated under the baseline and alternative cropping systems. Total profits are equal to revenue minus
the cost of production, with revenue equal to yield times prices and cost calculated based 2009 input
cost data.
The iterative process begins with the selection of a random year from 1980 to 2010. The selected year
(e.g., 1985) becomes the base year for that iteration. Commodity prices and the GDP deflator for the
base year are used directly in the calculation, whereas the yield from that year is used to calculate an
“adjusted yield.” The adjusted yield is calculated by adding a random term to the selected base yield.
This is done so as to not draw from the same yield frequency. This allows the model to proxy the
potential variation in yields that have been demonstrated historically, while preserving the correlation
between local production conditions and national output prices. Without the random error term, the
sample would be drawn from the historical distribution of yields; thus, the result would be the same
distribution as that of the historical data. The addition of a random percent error term allows for
variability yields outside of what has been observed historically.
The number of acres in production is multiplied by the adjusted yield to calculate total yield.
The product of total yield and the commodity price equals revenue. The input costs are adjusted using
the GDP ratio.
The difference between revenue and costs represents the potential profit obtained from producing a
particular crop under that iteration’s conditions. For a given iteration, the difference between the profit
under baseline and the alternative scenarios represents potential foregone profits for the irrigator if
they were to switch to the water conserving alternative.
It is important to note that these comparisons do not include a payment for leased water associated
with the conserved CU, so profits for the alternative cropping systems are expected to be less than the
baseline. Model output could be used by the irrigator to determine, given their risk preferences, the
amount of leasing revenue they would need to receive to offset the foregone profit associated with
switching to the alternative.
Applying the Model to a Representative Farm in Weld County, Colorado
To illustrate the model’s potential usefulness, results corresponding to a representative farm of 2,000
acres in Weld County, Colorado are presented below. Figure 2 illustrates the baseline and four
alternative scenarios considered. The scenarios considered here were selected based on conversations
with specialists at CSU and represent likely adaptations farmers would consider to reduce consumptive
water use.

Table 1 presents the average, standard deviation, coefficient of variation, minimum, and maximum
profit associated with the Baseline and Scenario runs generated by the model.
Table 1. Summary Statistics of Profits for a Representative Farm
Profit

Baseline

Scenario A

Scenario B

Scenario C

Scenario D

Average

265,240

176,836

103,044

199,517

285,354

St. Dev.

138,641

92,432

90,638

94,707

130,797

Coef. of
Var.

52

52

88

47

46

Min

-181,317

-120,884

-134,725

-87,893

-39,825

Max

535,758

357,190

431,053

401,131

724,882

Both in terms of average and relative variability in profits (i.e., coefficient of variation), Scenario D is
preferred over the other alternatives and the Baseline cropping pattern. The latter is true despite
recently high corn prices relative to the average over the 30-year sample period. To the extent that corn
prices remain high, all else equal, the model underestimates the true value of producing corn and
therefore also underestimate the opportunity cost of switching to any of the alternatives.
While the figures in Table 1 provide insight into the impact of each alternative on the distribution of
profits, they are difficult to compare given that the amount of water freed up, as well as the number of
acres impacted, differs across each alternatives. As an alternative, we calculate the difference in profits
between the Baseline and each of the scenarios and normalize them based on the amount of acres
impacted (Table 2) and the consumptive water use conserved (Table 3).
Table 2: Foregone Profits per Acre Converted from Corn
Scenario A

Scenario B

Scenario C

Scenario D

Average

132

238

65

-24

St. Dev.

72

160

70

90

Coef. of Var.

55

67

107

-384

Min

-91

-222

-126

-466

Max

268

643

247

256

Table 3: Foregone Profits per Acre Foot of Water Conserved (CU)
Scenario A

Scenario B

Scenario C

Scenario D

Mean

111

569

55

-46

St.Dev.

58

363

56

199

Coef. of Var.

52

64

102

-435

Min

-76

-519

-106

-1,060

Max

224

1,504

206

583

Acre Feet
Conserved

797

285

1,195

440

Again, it is important to keep in mind that profit estimates presented in Tables 2 and 3 represent
deviations from Baseline production where potential revenue from water leases is not factored in.
Which alternative is preferred? Tables 2 and 3 each provide the irrigator (and policy makers) with a
starting point for considering the type of returns they would need to get from leasing to offset losses in
productivity. The preferred alternative will depend on the risk preferences of individual producers and
the quantity of water needed. For more information about the project, and use of the model, please
contact Larisa Serbina ([email protected]) or Christopher Goemans
([email protected]).

Baseline

Scenarios

Figure 1. Model overview

Figure 2. Baseline cropping pattern and
four potential scenarios for analysis

Thermal preference of age-0 stonecats (Noturus flavus): Are thermal water quality standards protective for this specie

Thermal preference of age-0 stonecats (Noturus flavus): Are
thermal water quality standards protective for this species?
Basic Information
Thermal preference of age-0 stonecats (Noturus flavus): Are thermal water
quality standards protective for this species?
Project Number: 2012CO265B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional District: 4th
Research Category: Biological Sciences
Focus Category: Ecology, Law, Institutions, and Policy, None
Descriptors: None
Principal Investigators: Christopher A. Myrick
Title:

Publications
There are no publications.

Thermal preference of age-0 stonecats (Noturus flavus): Are thermal water quality standards protective
1 for th

Thermal Preference of Age-0 Stonecats (Noturus Flavus): Are Thermal Water Quality Standards
Protective for this Species?
Adam Herdrich, Master’s Candidate, Department of Fish, Wildlife, and Conservation Biology, Colorado
State University
Faculty Advisor: Christopher A. Myrick
Introduction
Transition zone streams, those coming off of the Rocky Mountains and transitioning onto the Great
Plains along the Front Range of Colorado, are under increasing pressure from anthropogenic sources.
Between the push for supplying drinking water for the growing population in this area, the invasion of
non-native aquatic species, and the effects of urbanization, these streams have been and will continue
to be impacted by human activities. The ecosystem-level effects inevitably trickle down to the fish and
insect communities inhabiting these stream segments, and create conditions that are suboptimal, or
even detrimental, to these assemblages.
Changes in the magnitude, timing, and duration of flows have serious impacts on these systems, but
another factor, the temperature or thermal regime, is of equal or greater importance. Temperature is
one of the most crucial factors in aquatic systems, largely because the vast majority of aquatic
organisms are poikilotherms, or cold-blooded, and their biology is directly tied to the environmental
temperature. All organisms have temperatures at which their fitness is maximized, and without the
ability to internally control their body temperatures, poikilotherms, such as the fish in transition zone
streams, are limited by the thermal heterogeneity offered by their environment.
The state of Colorado regulates water temperature through a tiered system that is based on the fish
communities that are present at the site being regulated. Thermal tolerance data are reviewed, and
regulations are set based on the most sensitive member of the fish assemblage present in the reach of
interest. The most sensitive species is generally assumed to be the one that is most vulnerable to water
temperature changes. Currently, Colorado develops independent standards for both acute (short-term)
and chronic (long-term) exposure and differentiates between warm and cold-water species and flowing
(e.g., streams, rivers) vs. impounded (e.g., ponds, reservoirs) bodies of water.
While thermal tolerance data are available for numerous fishes, the majority of studies have focused on
fishes that are valued from a commercial or recreational fishing standpoint, or that are candidate
species for protection under federal endangered species legislation. Until recently, relatively few studies
looked at native non-game fishes such as those that dominate the transition zone assemblages.
My research focused on the thermal biology of the stonecat (Notorus flavus; Figure 1), a species of small
catfish. The Colorado populations of stonecats are found in the St. Vrain River in the vicinity of
Longmont, Colorado, and in the Republican River near Wray, Colorado; (Figure 2). Specifically, I am
investigating whether the thermal regulations set by the State of Colorado Water Quality Control
Division are sufficiently protective of these rare fish.
The section of the St. Vrain River where stonecats occur is presently categorized as a Tier-I Aquatic
Warm-Life stream section with a Daily Maximum Temperature of 29°C. This means that the stream
temperature cannot exceed 29°C more than once in three years. This regulation is driven by the
presence of common shiner (Luxilus cornutus) and Johnny darter (Etheostoma nigrum) and is based on
the assumption that these fishes are the most sensitive to drastic thermal changes in this stream.

My research project was designed to test this assumption, and to expand the existing knowledge of
stonecat thermal biology, particularly as it relates to their thermal tolerance when acclimated to
summer-type temperatures. Prior research conducted at the Center for Lake Erie Area Research (The
Ohio State University) on thermal tolerance of stonecats acclimated to cold temperatures (1.6° C)
showed that they selected a temperature of 29 °C.
Methods
Adult stonecats (n = 20; total length: 209.75 ± 15.64 mm [mean ± S.D.]; wet weight: 105.05 ± 23.07 g)
collected from the St. Vrain River by Colorado Parks and Wildlife (CPW) biologists were delivered to
Colorado State University (CSU) where they were held in ambient (temperature & photoperiod)
conditions at the CSU Foothills Fisheries Laboratory. Six weeks prior to the trials, the temperature was
raised to 20°C at a rate of 2.0°C per week. This was done to simulate spring warming, culminating in
water temperatures found in the St. Vrain River over the summer. We simultaneously and incrementally
changed the photoperiod, culminating in a 14-hour day, also to mimic summer conditions (Figure 3) and
to account for any additional stress effects, due to a decreased window of activity, on the thermal
tolerance of the largely nocturnal stonecat. Stonecats were fed a mixed diet of live earthworms and
commercial fish feed (Hikari Massivore Delite).
I used the Critical Thermal Maximum (CTMax) approach, as modified by Underwood et al. (2012) to
measure the short-term thermal tolerance of the stonecats. The CTM methodology is a well-established
and widely used technique for evaluating the acute thermal tolerance of fish and other aquatic
organisms. The CDPHE thermal standards include specific guidance on how to translate the results of
CTMax tests into thermal standards. Because of the limited availability of stonecats, I was not able to
test fish at additional acclimation temperatures, nor was it possible to use a chronic and lethal test
methodology such as the incipient upper lethal temperature (IULT) approach.
The test apparatus was based on the system assembled by Underwood et al. (2012), with the notable
substitution of the 1.5-l aquaria with five larger 9-l aquaria (Figure 4) receiving 3 l/min of temperaturecontrolled water. The heated and ambient water were delivered to a mixing tank, then to aquariums to
increase the tank temperature by 0.3°C per minute. Fish were measured (to nearest mm) weighed (to
nearest g) and placed into the tanks (one fish per tank), and allowed to acclimate at ambient
temperatures for one hour before a trial was started. Fish behavior was observed and the trials were
ended after a sustained loss of equilibrium (LOE; greater than 10 s); with this loss of equilibrium, it can
be assumed that fish will not be able to escape rapidly warming water temperatures in a natural setting.
After LOE was observed, the water temperatures were recorded and the tanks were immediately
flushed with ambient temperature water, and final temperatures were recorded. Fish were then
returned to their holding tanks and monitored for 48 hours to check for delayed mortality. No fish were
reused, and all experiments were conducted under the protocol approved by the CSU Institutional
Animal Care and Use Committee (#12-3991A).
Results
The mean ± S. D. CTMax for the 20° C-acclimated stonecats was 32.6 ± 0.44° C (n = 20). A 1-way ANOVA
(JMP) showed a significant effect (P < 0.05) of total length on CTMax (Figure 5), and a non-significant
trend ( P = 0.09) wherein wet weight also influenced CTMax. No delayed mortality was observed.
Discussion
This study demonstrated that stonecats are capable of tolerating temperatures that are slightly lower
than those tolerated by other transition zone and eastern plains fishes such as the Johnny darter and
common shiner when acclimated to summer-type temperatures. Smith and Fausch (1997) reported that

the mean ± SE CTMax for Johnny darter acclimated to 20°C was 34 ± 0.32° C; Beitinger et al. (2000)
reported that the CTMax for common shiner acclimated to 26°C was 35.7 ± 0.39° C. Based on these
results, it appears that stonecats should receive serious consideration as one of the sensitive species
that can influence thermal classifications, particularly when their limited distribution is considered.
Additionally, the presence of a size effect highlights the importance of follow-up studies to determine
whether there are ontogenetic changes in the thermal tolerance of stonecats; if the larger adult fish are
indeed more sensitive to elevated temperatures, perhaps more protective standards are required to
protect them. From this study, it is clear that further research is warranted, both to better understand
the effects of fish size on thermal tolerance, and to complete a thermal tolerance polygon (a figure
showing the absolute thermal limits, upper and lower, for a fish species) for the stonecat.

Figure 1. The species studied was the stonecat
(Notorus flavus), a small, rare species of catfish.

Figure 2. Current distribution of Stonecats
(Noturus flavus) in Colorado

Figure 3. Photophase (length of daylight) for the Longmont, CO, area over one year

Figure 4. Schematic diagram of the thermal tolerance apparatus.
Key for schematic diagram of critical thermal tolerance apparatus:

1. Dynasense Mk 1 on/off relay temperature controller (model 221-017)
2. RTD temperature probe
3. Mixed water supply line (3/4” ID tubing); water is delivered from the mixed water sump (21) by the
mixed water pump (20).
4. Water mixing tank; dashed line indicates nominal water level just below constant head overflow
port.
5. Hot water supply line (3/4” ID tubing). Water is delivered from the hot water supply tank (22) by
the hot water pump (24).
6. Mixed water delivery line; this line delivers water to the mixed water distribution manifold (9).
7. Constant-head overflow line; this line maintains a constant water level in the mixing tank (4) and
delivers excess water to the mixed water sump (21).
8. Control cable from temperature controller (1) to hot water pump (24).
9. Mixed water delivery manifold; the manifold has ten individually-regulated outlets for delivery
water to the tolerance chambers (16).
10. Scientific Instruments Digi-Sense 10-channel scanning thermometer; the thermometer is connected
to 10 thermistor probes (11; only 3 are shown) and constantly monitors temperatures in the
tolerance chambers.
11. Thermistor probes (1 per tolerance chamber) that connect to the scanning thermometer (10).
12. Ambient water delivery line (3/4” ID tubing); this line delivers water to the ambient water
distribution manifold (13).
13. Ambient water distribution manifold; the manifold has ten individually-regulated outlets for delivery
water to the tolerance chambers (16).
14. Ambient water delivery tubing (3/8” ID); each chamber receives water from the ambient water
manifold (13) through one of these lines.
15. Mixed water delivery tubing (3/8” ID).
16. Thermal tolerance chamber.
17. Thermistor, connected to scanning thermometer (10) by wire (11). Each tolerance chamber was
fitted with a single thermistor.
18. Tolerance chamber overflow drain; these drained into the mixed water sump (21).
19. Insulated tank cover that rests on the hot water supply tank (22).
20. Pondmaster MagDrive submersible pump (model 18B) used as the mixed water delivery pump.
21. Mixed water sump, which receives water from the tolerance chambers (16) and the overflow from
the water mixing tank (4).
22. Hot water supply tank, fitted with an insulated cover (19).
23. Clepco Smart Heater (1.5 kW, 120V) with control unit and low-water shutoff. This heater sits in the
hot water supply tank and is used to maintain the water temperature at > 40°C.
24. Pondmaster MagDrive submersible pump (model 18B) used as the hot water delivery pump.

Figure 5. Effects of fish size (TL, in mm) on the critical thermal maxima - loss of equilibrium (CTMax-LOE)
of adult stonecats (Noturus flavus) acclimated to 20°C. The shaded area shows the 95 percent
confidence interval for the fitted regression line.

Simulation to Assess Alternative Treatment Units for a Local Wastewater Treatment Plant to Meet the New Effluent Nutrien

Biowin Simulation to Assess Alternative Treatment Units for
a Local Wastewater Treatment Plant to Meet the New
Effluent Nutrient Regulations
Basic Information
Biowin Simulation to Assess Alternative Treatment Units for a Local Wastewater
Treatment Plant to Meet the New Effluent Nutrient Regulations
Project Number: 2012CO266B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional
4th
District:
Research
Engineering
Category:
Focus Category: Wastewater, Law, Institutions, and Policy, Models
Descriptors: None
Principal
Pinar Omur-Ozbek
Investigators:
Title:

Publications
There are no publications.

Biowin Simulation to Assess Alternative Treatment Units for a Local Wastewater Treatment Plant to1Meet the

Biowin Simulation to Assess Alternative Treatment Units for a Local Wastewater Treatment Plant to
Meet the New Effluent Nutrient Regulations
Keerthivasan Venkatapathi, Civil and Environmental Engineering, Colorado State University
Faculty Advisor: Pinar Omur-Ozbek
Introduction
Wastewater treatment plant (WWTP) effluents may contribute significant levels of nutrients (i.e.,
nitrogen and phosphorus) to the surface waters. Elevated levels of nutrients lead to eutrophication of
the water bodies and may result in algal blooms during summer and fall. This becomes a major concern
if the water body is used as a drinking water source. Algae may store and release problematic
metabolites during the blooms, which include taste-and-odor compounds (e.g., geosmin and 2methylisoborneol), toxins (e.g. microcystins), and other organic compounds that may lead to
disinfection by-product formation during water treatment.
To prevent issues due to elevated levels of nutrients in surface waters, effluents from WWTPs are
monitored. Colorado Department of Public Health and Environment (CDPHE) regularly updates WWTP
effluent regulations to satisfy U.S. Environmental Protection Agency (EPA) guidelines. CDPHE has
recently adopted a new regulation, Nutrients Management Control Regulation (Regulation 85) in June,
2012 to be effective starting in September, 2012. Two levels of discharge limits are shown in Table 1:
one for the existing and another for the new WWTPs.
Table 1: CDPHE’s Regulation 85 discharge limits

Parameter
Total
Phosphorus
Total Inorganic
Nitrogen

Existing Discharges
Annual median

Existing Discharges
95th percentile

New Discharges
Annual median

New Discharges
95th percentile

1.0 mg/L

2.5 mg/L

0.7 mg/L

1.75 mg/L

15 mg/L

20 mg/L

7 mg/L

14 mg/L

City of Loveland WWTP, selected as the model system for this research, is located 50 miles north of
Denver, Colorado and employs a step feed activated sludge process with a treatment capacity of 10
million gallons per day (MGD). With new regulations, Loveland WWTP has to comply with the limits by
the next permit round in 2017. The effluent data, shown in Table 2, clearly indicate that Loveland WWTP
will not be able to meet the new regulation limits. To address this problem, existing Loveland WWTP
should be retrofitted or upgraded. Since upgrading is an expensive and time consuming process,
retrofitting the existing units was explored by this study to meet Regulation 85 by reducing the total
phosphorus (TP) to below one mg/L, and the total inorganic nitrogen (TIN) to below 15 mg/L.

1

Table 2: Influent and effluent concentrations for City of Loveland WWTP
Parameters
(Annual Average)
Flowrate
BOD
5

TSS
TKN
pH
NH
3

Total Inorganic Nitrogen
Total Phosphorus

Influent
Values-units
6.29 MGD

Effluent
Values-units
6.19 MGD

312 mg/L
273 mg/L
37.4 mg/L
7.49

7.6 mg/L
6.9 mg/L
2.2 mg/L
6.9

24.7 mg/L
N/A
6.6 mg/L

0.4 mg/L
19.38 mg/L
4 mg/L

Methods
Loveland WWTP was modeled and simulated using BioWin, proprietary software developed by
EnviroSim Associates Ltd. Loveland WWTP has units found in a conventional WWTP; the main difference
is the two identical treatment trains for the step feed activated sludge (AS) process (containing three
basins each). For the AS process, primary effluent is divided among the three anoxic/aerobic basins in a
predetermined ratio, with return activated sludge (RAS) (from the secondary clarifier) fed into the first
basin only. The effluent from the AS trains are sent to the secondary clarifiers. Figure 1 depicts a
simplified flowchart of Loveland WWTP.
Figure 1: Flowchart of City of Loveland WWTP

Existing step feed AS process that already contains three basins may be updated with the addition of
two more basins to convert to a five-stage Bardenpho process to achieve further nutrient removal. The
Bardenpho process utilizes a series of anaerobic, anoxic, aerobic (aeration), secondary anoxic and
aerobic (reaeration) basins (Figure 2). The goals of the Bardenpho process are: i) to release phosphorus
in the anaerobic basin and enhance its take up in the aerobic basins; and ii) to obtain nitrogen removal
through nitrification and denitrification by recycling effluent from aerobic to anoxic basin.

2

Figure 2: Flow diagram of the 5-stage Bardenpho process

Nitrate Recycle

Influent

Anaerobic

Anoxic

Aeration

Secondary Reaeration
Anoxic

Clarifier

Effluent

Return Sludge
Waste
Sludge

Figure 3: BioWin model of the existing City of Loveland WWTP (top) and proposed 5-stage Bardenpho
process (bottom)
Effluent

Influent

Anoxic 1

Aerator 1

Anoxic 2

Aerator 2

Anoxic 3

Anoxic 4

Aerator 3

Aerator 5

Anoxic 5

Aerator 6

Anoxic 6

Aerator 4

WAS

Priamary Sludge

Effluent
Influent
Anaerobic

Priamary Sludge

Anoxic 1

Aerator

Anoxic 2

Re-Aeraion

WAS

3

Table 3: Effluent concentrations from the plant and BioWin model
Parameters

Actual Plant Effluent
(mg/L)
5.30

BioWin Model Effluent
(mg/L)
4.71

Total Suspended Solids

6.19

10.43

NH3

0.26

1.31

Total Kjehldahl Nitrogen

2.01

3.83

Total Phosphorus

3.91

3.85

BOD

5

For this research, the five-stage Bardenpho process was modeled with only one treatment train instead
of the two trains as in the existing configuration (Figure 3). To ensure the validity of the preset
parameters in the BioWin software, the existing step feed AS process was simulated, and Table 3 shows
the measured and modeled effluent concentrations. The model was accepted to be reliable in predicting
the effluent concentrations for the five-stage Bardenpho process.
Simulations were performed at 13.5 ºC and 18.5 ºC to mimic winter and summer wastewater
temperatures, respectively. A higher influent wastewater flowrate of 12 MGD was modeled to
accommodate for population growth and future plant expansion. Basin volumes were varied based on
the ideal minimum and maximum hydraulic retention time (HRT) guidelines provided by Wastewater
Treatment Plants Task Force of the Water Environment Federation and the American Society of Civil
Engineers. Table 4 shows the HRTs and volumes of the basins that were selected to simulate the 5-stage
Bardenpho process.
Table 4: 5-stage Bardenpho process hydraulic detention times (HRT) and basin volumes
Basin

Lower Design HRTs

Higher Design HRTs

HRT (d) Volume (Mil.gal) HRT (d) Volume (Mil.gal)
Anaerobic

1

0.96

2

1.92

Anoxic 1

2

1.92

4

3.84

Aerobic 1

4

3.84

6

5.76

Anoxic 2

2

1.92

4

3.84

Aerobic 2

0.5

0.48

1

0.96

Internal recycle flowrate (IR) of mixed liquor suspended solids (MLSS) (i.e. microorganisms performing
biological treatment and other solids) was kept at the same flowrate as the original influent wastewater
flowrate (12 MGD). To determine the optimal basin volumes for a given temperature and selected HRTs,
waste activated sludge (WAS) flowrate, which controls the sludge age, was varied from 0.2 MGD to 1
MGD. Methanol was added to the secondary anoxic basin as an additional carbon source for
4

microorganism growth, to improve denitrification. BioWin controller (similar to process control
equipment available in a WWTP to have real time control over aeration rate, pump speed and chemical
additions) was used to determine the optimal methanol dosage by averaging the methanol flowrate
determined by the software after a dynamic simulation for 24 hours, a flowrate of 250 gal/d was
selected for the simulations.
Results and Discussion
The goal of the simulations was to determine the optimum HRTs, basin volumes and WAS flowrates to
meet the Regulation 85 by reducing the TP to below 1 mg/L, and the TIN to below 15 mg/L. The results
from the simulations performed for summer and winter temperatures for selected HRTs and basin
volumes (Table 4) are provided in Figures 4 and 5 for varying WAS.
Figure 4: Effluent TP concentrations for various WAS flow rates
TP values for summer and winter lower
HRT
1.6

1.02

1
0.8

1.2

0.98

0.67

0.6

Summer

mg/L

0.48
0.32

0.4

Winter

0.39

0.31

0.28

0.4

0.6

0.75
0.74

0.6
0.8
WAS(MGD)

Summer
Winter

0.38
0.39

0.2

0.21

0
0.2

0.8

1.4

1.2

0.4

0.43

0.2

1

1.36

1.29

1.4
mg/L

1.2

TP values for summer and winter higher
HRT

0.26

0.31

0.6
WAS (MGD)

0.8

0

1

0.2

0.4

1

Figure 5: Effluent TIN concentrations for various WAS flowrates

17.69

18
15
mg/L

12

Summer

8.8

Winter

9
6
3

1.32

1.91
1.01

0
0.2

3.37

0.4

1.2

1.49

2.91

1.98

0.6
0.8
WAS(MGD)

1

TIN values for summer and winter lower
HRT
20
18
16
14
12
10
8
6
4
2
0

17.55

17.32

14.91
15.02

mg/L

21

TIN values for summer and winter higher
HRT

Summer
Winter
3.09
1.39
1.13
0.2

1.33
0.4

2.82

4.52

0.6
0.8
WAS(MGD)

1

5

Results showed that desired effluent concentrations for TP and TIN are obtained with higher design
HRTs and basin volumes. Hence other effluent parameters determined using the higher design HRTs are
provided in Table 5 for an influent flowrate of 12 MGD, IR of 12 MGD and methanol flowrate of 250
gal/d, for both summer and winter temperatures. As expected, the treatment efficiency is lowered
during winter due to slowed metabolic reactions of the microorganisms used in the biological treatment
units.
Table 5: Effluent concentrations determined by BioWin simulations for higher design HRTs
SUMMER
WINTER
WAS
TIN
TP
BOD5
TSS
TIN
TP
BOD5
(MGD)
(mg/L)
(mg/L)
(mg/L)
(mg/L)
(mg/L)
(mg/L)
(mg/L)
0.2
1.01
0.98
3.98
11.83
1.32
1.02
4.15
0.4
1.2
0.43
3.18
7
1.91
0.48
3.33
0.6
1.49
0.31
2.74
5.05
3.37
0.32
3.29
0.8
1.98
0.28
2.57
3.97
8.8
0.39
2.96
1
2.91
0.21
2.81
3.32
17.69
0.67
3.13

TSS
(mg/L)
11.95
7.06
5.04
3.95
3.26

TP removal increases by increasing WAS flowrate for summer, however maximum efficiency was
obtained at 0.6 MGD for winter. For TIN removal, efficiency was inversely related to WAS flowrates for
both summer and winter, and hence lower WAS flowrates should be selected. It should be noted that,
except for the WAS flowrate of 1 MGD for winter temperatures, all other simulated WAS flowrates meet
the regulations for TIN concentrations in effluent with 0.2 MGD just making the limit for TP.
Conclusions
BioWin simulations are helpful in guiding the WWTPs in determining how to improve and update their
existing processes with minimal capital and operational costs. It should be noted, however, that the
effluent results should be evaluated with a factor of safety as the preset simulation parameters for
BioWin may not exactly match the conditions in the simulated WWTP. This study determined that, for
Loveland WWTP, retrofitting the existing plant with two additional basins and converting the treatment
process to 5-stage Bardenpho will enable them to meet the new effluent nutrient regulations.
The suggested design parameters for the new process and the obtained effluent nutrient levels are as
follows: WAS flowrate of 0.6 MGD results in optimal effluent concentration of 0.31 mg/L for TP and 1.49
mg/TIN for summer (18.5 oC) and 0.32 mg/L for TP and 3.37 mg/L for TIN for winter (13.5 oC). Design
HRT of 2 days for anaerobic, 4 days for anoxic, 6 days for aerobic, 4 days for secondary anoxic and 1 day
for reaeration was chosen with corresponding volumes of 1.92 mil.gal, 3.84 mil.gal, 5.76 mil.gal, 3.84
mil.gal and 0.96 mil.gal, respectively. SRT was approximately 14 days for both summer and winter
conditions.

6

Characterize the Connection between Alluvial Groundwater and Streamflow Water Under Augmentation at the Tamarack Ra

Using Water Chemistry to Characterize the Connection
between Alluvial Groundwater and Streamflow Water Under
Augmentation at the Tamarack Ranch State Wildlife Area,
Colorado
Basic Information
Using Water Chemistry to Characterize the Connection between Alluvial Groundwater
Title: and Streamflow Water Under Augmentation at the Tamarack Ranch State Wildlife Area,
Colorado
Project Number: 2012CO267B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional
4th
District:
Research
Ground-water Flow and Transport
Category:
Focus Category: Groundwater, Hydrology, Hydrogeochemistry
Descriptors: None
Principal
John Stednick
Investigators:

Publications
There are no publications.

Using Water Chemistry to Characterize the Connection between Alluvial Groundwater and Streamflow
1 Wate

Using Water Chemistry to Characterize the Connection between Alluvial Groundwater and Streamflow
Water under Argumentation at the Tamarack Ranch State Wildlife Area, Colorado
Jason Roudebush, MS Candidate, Watershed Science, Colorado State University
Faculty Advisor: John D. Stednick
Introduction The presence of four threatened or endangered species—the whooping crane (Grus
americana), interior least tern (Sterna antillarum), piping plover (Charadrius melodus), and pallid
sturgeon (Scaphirhynchus albus)—on the Platte River in Nebraska prompted the states of Colorado,
Wyoming, and Nebraska to enter into a cooperative Tri-State Agreement with the U.S. Department of
the Interior to implement recovery efforts by improving riverine habitats. The Platte River Recovery
Implementation Program (PRRIP) began on January 1, 2007, still allowing state water use and
development to continue. Wyoming’s obligation under PRRIP is met by operating an environmental
account in Pathfinder Reservoir to retime flows during periods of target flow shortages. Nebraska
operates a similar environmental account in Lake McConaughy to retime flows while also providing
additional land habitat in the Lexington to Chapman reach of the Platte River. Colorado’s contribution is
groundwater recharge at Tamarack Ranch State Wildlife Area (TRSWA) near Crook.
Managed groundwater recharge at TRSWA is designed to meet the state of Colorado’s obligation to
increase streamflow in the Platte River by an average of 10,000 acre-feet per year. This obligation is met
by pumping alluvial groundwater (in priority and during times of surplus) upgradient to recharge ponds
where the water seeps into the ground and returns to the river at a later time. Under designed
conditions, recharge water flows through the subsurface with a timing that supplements streamflow
during periods of critical low flow. The South Platte River flow regime is dominated by snowmelt in the
late spring and early summer, so the target window for streamflow accretions is designed to occur
between August and November.
Modeling Approach
The three most common approaches for estimating the effects of groundwater pumping on streamflow
are the Glover solution (Glover and Balmer, 1954), stream depletion factor (SDF) method (Jenkins,
1968), and numerical methods such as MODFLOW (McDonald and Harbaugh, 1988). The Glover and SDF
analytical methods are both used in water rights decisions but oversimplify physical conditions (Fox et
al., 2002). MODFLOW, a widely used code for numerical modeling, is capable of simulating fully threedimensional flow in systems that are horizontally and vertically heterogeneous and have complex
boundary conditions (Barlow and Leake, 2012).
The original groundwater model for TRSWA was developed by Colorado Parks and Wildlife, formerly the
Colorado Division of Wildlife (Halstead and Flory, 2003). This MODFLOW model was developed and
calibrated based on aquifer conditions in the vicinity of the recharge wells to evaluate groundwatersurface water exchange (1996CW1063, 2012). Much of the aquifer characterization was based on earlier
work utilizing drill log data (Hurr and Schneider, 1972). Additional work by Colorado State University
(CSU) has better determined these physical conditions. For instance, CSU hydrology research at TRSWA
inferred groundwater flow pathways from the recharge ponds to the river by contouring the water table
elevation from measurements taken at a network of piezometers (Beckman, 2007). Further research
confirmed this local groundwater flow direction with a fluorescein tracer study (Donnelly, 2012).
Hydrogeophysical investigations into the subsurface stratigraphy of the eolian sands, alluvial sediments,
and shale confining unit suggested the presence of a paleo-channel beneath the recharge ponds that
1

could influence the flow pathways of recharge water (Poceta, 2005). In order to better map the
potential flow pathways and quantify streamflow accretion, a groundwater flow model using MODFLOW
is being constructed to utilize the existing onsite hydrologic and geophysics research.
The geometry of the South Platte alluvial aquifer is more complex than previously suggested. A recent
surface Electrical Resistivity Tomography (ERT) survey defines a detailed topography of the confining
bedrock surface in the area located between the recharge ponds in the eolian sand hills and the river
(Lonsert et al., 2013). The ERT data were used in combination with additional drill logs to create a
subsurface bedrock map (Figure 1), which revealed steeper topographic relief compared to previous
interpretation of the shale bedrock (Hurr and Schneider, 1972). The incorporation of the new
geophysical data into the model allows a better understanding of the potential flow pathways from the
recharge ponds back to the river.
The three-dimensional model of the unconfined aquifer consists of three layers. The uppermost layer
represents the eolian sand hills and the bottom two layers represent the alluvium. The alluvium was
divided into two layers to allow for the simulation of vertical gradients. The model domain is 17
kilometers (east to west) by 10 kilometers (north to south) by an average of 42 m deep and contains
approximately 120,000 active cells. Grid spacing was refined in the area of the recharge ponds to
account for the steep vertical hydraulic gradients. The lateral boundaries to the north and south are
formed by the edges of the alluvial deposits digitized from USGS Geologic Maps of the area (Scott, 1978)
and are considered to be no-flow boundaries. The western edge of the model is located along State
Highway 55 where the Colorado Division of Water Resources (CDWR) operates a streamflow gaging
station; the eastern edge is 25 kilometers downstream.
The South Platte River is simulated as a partially penetrating stream in Layer 2 using the StreamflowRouting (SFR1) package. The SFR1 package calculates stream baseflow and groundwater-surface water
exchange for each of the stream cells that are independent of the groundwater budget (Prudic et al.,
2004). Advantages of using the SFR1 package include: the model computes baseflow within each cell
internally, and stream stage does not need to be specified for each cell. The Gage package (GAGE) is
used to designate cells in the model for monitoring so that separate output files are written for graphical
post processing of the calculated data. The western model boundary is aligned with the CDWR gaging
station and defines the uppermost reach of the river. This provides for an accurate representation of
streamflow entering the model; subsequent contributions to base flow downstream of the gage
represent streamflow accretions from recharge operations and irrigation return flow.
Expected Outcomes and Impacts
Using new hydrogeophysical data, model calculations of baseflow and groundwater-surface water
exchange will provide an enhanced understanding of how recharge water reaches the stream and where
streamflow accretion is occurring. Achieving a more fully informed understanding of these physical
processes is critical in evaluating the efficiency of recharge operations at TRSWA, and is an essential
component in accomplishing the goal of accurately augmenting streamflow in the desired period. The
modeling results will form the basis of an MS Thesis in Watershed Science at CSU and can subsequently
be used to facilitate the design and placement of future conjunctive use sites.

2

Acknowledgements
Funding for this research is provided by the Colorado Department of Parks and Wildlife and the
Colorado Water Institute. Professor Michael Ronayne of CSU provided helpful suggestions on the
modeling.

Figure 1. Topographic bedrock map (five times
vertical exaggeration) in the vicinity of the
recharge ponds based on the additional
geophysical investigation

3

Information Transfer Program Introduction

Information Transfer Program Introduction
Requests from the Colorado legislature to facilitate and inform basin-level discussions of water resources and
help develop an interbasin compact for water management purposes emphasized the role Colorado Water
Institute plays in providing a nexus of information. Some major technology transfer efforts this year include:
• Providing training for Extension staff in various water basins to help facilitate discussions of water
resources
• Encouraging interaction and discussion of issues between water managers, policy makers, legislators,
and researchers at conferences and workshops
• Publishing the bi-monthly newsletter, which emphasizes water research and current water issues
• Posting and distributing all previously published CWI reports to the web for easier access
• Working with land grant universities and water institutes in the intermountain West to connect
university research with information needs of Western Water Council, Family Farm Alliance, and
other stakeholder groups
• Working closely with the Colorado Water Congress, Colorado Foundation for Water Education,
USDA-CSREES funded National Water Program to provide educational programs to address
identified needs

Information Transfer Program Introduction

1

Technology Transfer and Information Dissemination

Technology Transfer and Information Dissemination
Basic Information
Title: Technology Transfer and Information Dissemination
Project Number: 2012CO256B
Start Date: 3/1/2012
End Date: 2/28/2013
Funding Source: 104B
Congressional District: 4th
Research Category: Not Applicable
Focus Category: None, None, None
Descriptors: None
Principal Investigators: Reagan M. Waskom

Publications
1. Colorado Water Newsletter, Volume 29 - Issue 2 (March/April 2012), Colorado Water Institute,
Colorado State University, Fort Collins Colorado, 33 pages.
2. Colorado Water Newsletter, Volume 29 - Issue 3 (May/June 2012), Colorado Water Institute,
Colorado State University, Fort Collins Colorado, 33 pages.
3. Colorado Water Newsletter, Volume 29 - Issue 4 (July/August 2012), Colorado Water Institute,
Colorado State University, Fort Collins Colorado, 37 pages.
4. Colorado Water Newsletter, Volume 29 - Issue 5 (September/October 2012), Colorado Water
Institute, Colorado State University, Fort Collins Colorado, 37 pages.
5. Colorado Water Newsletter, Volume 29 - Issue 6 (November/December 2012), Colorado Water
Institute, Colorado State University, Fort Collins Colorado, 41 pages.
6. Colorado Water Newsletter, Volume 30 - Issue 1 (January/February 2013), Colorado Water Institute,
Colorado State University, Fort Collins Colorado, 41 pages.
7. Bauder, Troy, et al. 2012. Agricultural Chemicals & Groundwater Protection in Colorado. Colorado
Water Institute, Colorado State University, Fort Collins, CO. 51 pages.
www.cwi.colostate.edu/publications/SR/23.pdf
8. Gates, Timothy K, et al. June 2012. Irrigation Practices, Water Consumption, & Return Flows in
Colorado's Lower Arkansas River Valley. Colorado State Institute, Colorado State University, Fort
Collins, CO. 116 pages. www.cwi.colostate.edu/publications/CR/221.pdf
9. Lukas, Jeffery J., Lisa Wade, and Balaji Rajagopalan. October 2012. Paleohydrology of the Lower
Colorado River Basin and Implications for Water Supply Availability. Colorado Water Institute,
Colorado State University, Fort Collins, CO. 34 pages.
www.cwi.colostate.edu/publications/CR/223.pdf

Technology Transfer and Information Dissemination

1

Colorado Water Institute Activities


The 2012 Summer Water and Energy Conference: The Balance of Power, Colorado Water
Congress, August 15 – August 17, 2012



32rd Annual Hydrology Days, American Geophysical Union, March 21 - March 23, 2012



Evapotranspiration Workshop, Colorado State Extension, March 21, 2012



Celebrating 10 Years of Statewide Water Education with the CFWE, Colorado Foundation for
Water Education, April 2012



Colorado Water 2012: Celebrating a Year of Anniversaries, Education, and Bringing Awareness to
Water in the West, 2012



Water Resource Education Curriculum Crew (The WRECking Crew), Colorado State University
Extension, Colorado Water Institute and Colorado Water Conservation Board



Colorado Water Conservation Board 2012 Drought Conference, CWCB,
September 19 – September 20, 2012



Water and Sustainability, Colorado State University Water Café, Colorado State University Water
Center and School of Global Environmental Sustainability, March 22 - 23, 2013



Addressing Global Water Resource Challenges with Local Expertise, GRAD592, Interdisciplinary
Water Resources Seminar, Fall 2012



Colorado Water, Colorado Water Institute, March 2012 – February 2013

advent of nanotechnology has created a variety of tiny
nanoparticles (10-9 m), and we have yet to understand
their potential impact on human health or to implement
treatment processes to remove them from drinking water.
Shackelford’s research goals have also propelled his goals
in teaching—he developed the CSU graduate program
in Geoenvironmental Engineering. Shackelford explains
geoenvironmental engineering as a, “broad-based term
reflecting the multidisciplinary aspects of soil-environmental problems” that can include chemistry, biology, and
other areas, according to a 2005 keynote presentation by
Shackelford in Japan.
“I used my diverse background as a momentum to
establish a program here that will benefit my students,” says
Shackelford of the geoenvironmental program at CSU.
Students in the program take two core classes in remediation and containment, and the elective class list varies
from Aqueous Chemistry to Groundwater Engineering

to the traditionally geotechnical Foundation Engineering.
“I encourage them to take courses outside of Civil
Engineering,” he says. If nothing else, Shackelford says
it’s important for them to be able to communicate with
professionals in related careers.
Shackelford says his recent appointment as Associate
Department Head of Civil and Environmental Engineering
will allow him to learn more about administration, which
he says is completely different from his current research
and teaching activities. He says he’ll find out if he intends
to move his career in that direction with his experience in
this position.
While he’s looking forward to the challenge of moving
forward in his career, Shackelford says he’ll always enjoy
his research and teaching, which he says are one and the
same. “That’s the main reason I love my job,” he says—“I
essentially get paid to learn.”

The 2012 Summer Water and Energy Conference: The Balance of Power
COLORADO WATER CONGRESS
In partnership with Colorado Coal and Power Generation
Steamboat Springs, Colorado
August 15-17, 2012
Workshops
Weather, Water Supply, and Wildland Fire
Public Trust, Public Values, and Public Interest
Endangered Species
Conference Sessions
The Regional Impact of the National Economy
The Water and Energy Balance
The Political Balance of Power
State Budget and Severance Tax
National Agenda on Balanced Fuels
Permitting and Project Planning
Scenario Planning
The Power Balance in the 2012 Election
Public Event
Interim Water Resources Review Committee
Please join us for the 2012 premier summer event for water.
For registration information, see our website at
cowatercongress.org

Figure 2. Left: Minimum-tillage plot
(left) next to conventionally plowed plot
at field demonstration site.
Figure 3. Right: Strip-tillage field,
named for the prepared strips of soil
and the undisturbed residue on the rest
of the field. The seed will be planted
directly into those prepared strips.
Photos by Erik Wardle

an opportunity for producers, government staff, and
industry representatives to share experiences and ideas on
conservation tillage. The primary benefit of this project is
an increased understanding of the possibilities of conservation tillage under furrow irrigated cropping systems within
Colorado. The objective is that an increased understanding
will lead to greater experimentation with, and adoption
of, tillage practices that conserve soil and water resources
and reduce energy demands. Complementary outreach
materials on the subject will include updated electronic
and hard copy materials that will be available to help
producers make educated decisions regarding adoption
of these practices. This work will also add to the body
of knowledge on the impacts of conservation tillage on
irrigation runoff water quantity and quality, particularly
nutrients and sediment.

The Value of Collaboration
Drawing upon experience and expertise of producers and
private and public sector technical experts has enriched
project planning and will certainly enhance its outcomes. It
is important to note that although adoption of conservation
tillage is not as wide spread as would be desirable in the
Northern Front Range, numerous innovative farmers in the
area are making these practices work for them. Working
closely with these producers has brought technical
expertise and ensures that the information produced by
the project will fill a need to help other farmers make
key management decisions. Our private sector partners
have also been invaluable to the productivity and ongoing
success of the project. In an era of limited resources,
collaboration among private and public sector colleagues is
increasingly important to maximize the impact of research
and demonstration work in our state.

Background photo by Bill Cotton

16

The Water Center of Colorado State University

USDA-Natural Resource Research Center,
Building D, Fort Collins, CO

March 21, 8:30 a.m. - 4:30 p.m.
Topics:
Recent Trends in Evapotranspiration Calculations and Data
Case Study:
Estimating Historic Consumptive Use
Luncheon Speaker:
Marvin Jensen, “Use of Supporting Data in Estimating and
Confirming ET Estimates”
Cost:
$200 (all profits go to support CoAgMet weather station network)
Registration:
To register, please visit http://col.st/zT7ZFc
Contact Tom Trout for further information, [email protected]

Celebrating 10 Years of Statewide
Water Education with the CFWE
Caitlin Coleman, Program Associate, Colorado Foundation for Water Education

In a Nutshell
• CFWE celebrates a
successful decade, and
looks ahead to expanding
its reach toward the
business community and
elected officials

E

veryone makes choices about
water, whether it’s at home or on a
larger scale. When people understand
the complexities of water issues,
they make better decisions—that’s
the philosophy of the Colorado
Foundation for Water Education
(CFWE), Colorado’s only statewide
nonpartisan nonprofit water educator.
CFWE just celebrated its 10th
anniversary.
“In Colorado, water is a scarce
resource and the competition for
that resource is going to get more
and more difficult in the future,”

says CFWE executive director,
Nicole Seltzer. “Everybody needs to
understand the implications of their
water use on a personal and a policy
level.”
For the past decade, CFWE has been
advancing its mission to promote
better understanding of Colorado’s
water resources and issues by
providing balanced and accurate
information and education, helping
Coloradans “Speak Fluent Water.”
Over the last 10 years, things have
changed in Colorado and at the
Foundation— priorities have shifted,
staff and board members have
transitioned in and out, and new
programs have started. As CFWE’s
next decade begins, the landscape of
water education continues to shift.
“[The CFWE] has really grown and
developed; it’s become a lot richer
than I ever saw,” says vice president
of the CFWE board and Colorado
Supreme Court Justice Gregory
Hobbs.

Today CFWE boasts a solid backbone
of basic water information and
educational programming but also
enhances leadership among water
professionals, creates networking
opportunities, helps advance the
water planning dialogue in the state,
and reaches out to those who aren’t
already involved in the world of
Colorado water.
That basic, digestible water
information is what CFWE was
founded upon and continues to be
an essential part of the organization.
“The bedrock of [CFWE] is having
a reliable source, the publications
are a perfect example,” says Greg
Johnson, a representative of the
Colorado Water Conservation Board
and CFWE board member. “Really
being able to rely on what you know
is a good go-to source whether it’s
publications or your website or your
upcoming tour—it’s critical,” Johnson
says.
When CFWE started in 2002, it
came on the heels of many failed
attempts to create a water education
foundation funded solely through
grants. The 2002 success of launching
Nicole Seltzer and Justice Hobbs honoring
CFWE’s legislative founder, Diane Hoppe
during the 10th Anniversary Celebration.

Courtesy of CFWE

“We provide an
important professional
networking opportunity
for water educators.”
–Nicole Seltzer, CFWE
Executive Director

20

The WaTer CenTer of Colorado STaTe UniverSiTy

the nonprofit was due to legislation
and strong financial support from the
Colorado Water Conservation Board
(CWCB). “It was a real long-term
investment by the state of Colorado,”
Seltzer says. Hobbs echoes the
importance of that support—water
professionals came together with
the shared sentiment that Colorado
needed an organization focused on
nonbiased statewide water education.
“We can point to a law that the
legislature passed that is unlike
anything else that I know about in the
water field,” Hobbs says. “The fact that
the state of Colorado has decided to
support a non-advocacy, nonpolitical
water foundation to communicate
with people is extraordinary.”
In addition to legal support of the
Foundation came the sustained
financial support from the Colorado
Water Conservation Board. “It was
solely because of that support from
the State that we’ve been able to do
what we’ve done for the last ten years,”
Seltzer says.
That work has also been important
to the state. “CFWE is a fair and
balanced third party that can
convey a lot of the messages that
[the CWCB] may not even have the
proper position to convey, let alone
the resources to do it,” Johnson says.
“[CFWE] can stand outside the fray of
political issues and is not the official
state entity—I think there is a lot of
power in that unbiased position that
the Foundation holds.”
That strong support created a CFWE
determined to quickly prove its
worth. “There was a real pressure to
deliver tangible product very quickly,
right out of the gates to show the State
that we were capable of producing
useful educational products,” Seltzer
says.
At the very beginning, Hobbs
remembers working on a map
illustrating the beneficial uses of
water; he then volunteered to write

The Colorado Foundation for Water Education (CFWE) celebrated its 10th anniversary in April 2012
with a reception at the Governor’s Mansion in Denver.

Courtesy of CFWE

the Citizen’s Guide to Colorado Water
Law— so began CFWE’s Citizen’s
Guide Series, which now covers nine
different Colorado water topics. To
replicate some of the work done by
a water education foundation in
California, CFWE began leading
river basin tours. An early executive
director, Karla Brown, came up with
the concept of creating Headwaters
magazine. All of these programs have
remained and grown as the “meat
and potatoes of water education,”
says CFWE board assistant secretary
and director of the Colorado Water
Institute at Colorado State University,
Reagan Waskom.
The Foundation’s work has started
to extend beyond those basic
products. “We provide an important
professional networking opportunity
for water educators,” Seltzer says.
“Before CFWE was created, there was
nobody that a water educator could
go to for help, advice, networking, or
ideas. We provide a strong network
and we can get best practices
out there.” That network and the
Foundation’s constant work with
water issues brings more visibility
to water in Colorado and raises
awareness about water on a consistent
basis, Seltzer says. “We’re bringing

Colorado WaTer — JanUary/feBrUary 2013

everybody together in service to
good effective water education in
Colorado.”
The Foundation has helped the
CWCB convene stakeholders across
the state to spread the message and
interest of the Statewide Water Supply
Initiative and planning for Colorado’s
water future. “I think that’s helped a
lot with the engagement that we have
with the roundtable process,” Johnson
says. Basin roundtables bring together
local stakeholders and meet in river
basins across the state to discuss the
local water use priorities and use that
dialogue to plan for future pressures
on water supply. “The roundtables
have helped change the game locally
and CFWE has been a partner in
that conversation,” Waskom says.
“CFWE has helped take the findings
and understandings of the Statewide
Water Supply Initiative out to the
public as well.”
Colorado Water 2012, the statewide
celebration of water, was spearheaded
by CFWE as another mode of
bringing people together around
water. “2012 happened because
of a decade of good solid work,”
Waskom says. For Water 2012, CFWE
convened partners and volunteers
across the state, profiled and shared

21

the work of water educators across
the state, started a blog that speaks
to the general public, and helped
bring water festivals and other public
events together under a common
theme—making the small events part
of something bigger, Seltzer says. “In
Water 2012, working with the media,
doing regular news articles, I think
all of that work has greatly expanded
the reach of water education in
Colorado,” Seltzer says.
Launching from 2012 and into the
next decade, the Foundation will
continue to expand that reach. “That’s
who we’re looking at as our next
audience, people interested in water
issues. Then we can work with them
to cross the spectrum from increasing
water awareness to understanding to
participation,” Seltzer says.
Some board members think that role
could expand beyond the borders

of Colorado. “Our impact and base
could be much larger,” Waskom
says. “Colorado is an amazing place
to study water. I think that people
around the world could learn from
us.”
As water becomes increasingly scarce,
competition for water will gain more
national importance, Johnson says.
“Having your materials, there may
be room for an increased voice for
the Foundation,” Johnson says. “To
have that good solid background
educational material available so we
can inform any policy discussions at
the national level too.”
The organization is celebrating the
fact that it has existed for ten years,
but is at a turning point. “It’s been
very successful,” Johnson says. “I
also think absolutely, it’s just the
beginning.”

Over the last 18 months, CFWE has
expanded its reach, budget, and staff
capacity. “I’m really looking forward
to the next ten years, continued
growth and reaching more and more
people with the basics of water in
Colorado,” Seltzer says. In the coming
years look forward to the Foundation’s
role expanding as a professional
development resource for water
educators and branching out to reach
new audiences such as the business
community and elected officials.
“There’s a lot of potential moving
forward,” Johnson says. “[The
Foundation] is something you feel
a part of, you have a sense of pride
in—it’s one of those local institutions
you support. It’s nice to have a group
like the Foundation that includes a
broad base of various water folks. It’s
not just water conservation or Water
Congress, it’s all of the above, it’s
everything.”

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Colorado Water 2012
Celebrating a Year of Anniversaries, Education, and
Bringing Awareness to Water in the West
Nona Shipman, Assistant Project Coordinator, Colorado Water 2012

In a Nutshell
• The 2012 Year of
Water (“Water 2012”)
celebrated water in
Colorado, including the
anniversaries of several
fundamental water
organizations in the state
• Water 2012 faced
challenges, such as
reaching certain parts of
the state and sectors of
the public
• Successes included
reaching Water 2012’s
goal of exposing
500,000 people to its
message and creating
partnerships to provide
education materials to
educators

“

2012 is a notable year in Colorado’s
history around water. 75 years ago
many of the organizations and laws
that govern how we use, manage, and
administer Colorado’s water were
born. In 2012 Coloradans will come
together to honor the hard work of
those who came before us, participate
in solving the tough challenges that
lie ahead, and celebrate our most
important natural resource,” said
Governor John Hickenlooper after
he officially declared 2012 the Year
of Water in January 2012. And he

was exactly right. 2012 served as
the year for recognizing water as
a necessary and vital resource
in Colorado and celebrating
everything that it is today, has
been, and will be. To honor the
organizations celebrating major
anniversaries and to show equal
respect to the natural resource that
allows us all to live in a dry arid
state, a statewide water awareness
campaign was created named
Colorado Water 2012.
It is important to mention the
organizations and legislation
celebrating anniversaries that got the
idea of Colorado Water 2012 off the
ground:
• 75th anniversary of the Colorado
Water Conservation Board
• 75th anniversary of the Colorado
River Water Conservation District
• 75th anniversary of the Northern
Colorado Water Conservancy
District
• 50th anniversary of the FryingpanArkansas Project
• 10th anniversary of the Colorado
Foundation for Water Education
In addition to these anniversaries,
more and more significant
anniversaries came out of the
woodwork, such as the 40th
anniversary of the Clean Water
Act, the 100th anniversary of the
Rio Grande Reservoir, and the 50th
anniversary of the Bear Creek Water
and Sanitation District that were
recognized. The Colorado Foundation
for Water Education was not only

Colorado WaTer — JanUary/feBrUary 2013

celebrating ten years but also took on
the responsibility to spearhead the
entire campaign.
Water 2012, as it was known, aimed
to bring awareness to water as a
precious resource through activities
and events held across the state.
In order to do this, six committees
were assembled. Each committee
brought different qualities to the table
with different focuses, but with one
common goal: to celebrate water in
Colorado through fun educational
activities. Each committee focused
on a task such as assembling a Water
2012 Book Club and conducting
author presentations, circulating
informational displays to Colorado
libraries and museums, and installing
rain gauges in Colorado schools. In
addition to the committees, Water
2012 had hundreds of partners
located all over the state conducting
their own events with a Water 2012
presence. In total there were over 400
Water 2012 related events in the Year
of Water.

23

1
2

3

1. Some Water 2012 swag created by different partners throughout the year. Photo by Nona Shipmen
2. Volunteers and committee leader, Marcee Camenson, pose while wearing their Fort Collins Water
Festival/Water 2012 t-shirts. Courtesy of Marcee Camenson
3. Featured Water 2012 Book Club authors Jon Waterman, Justice Greg Hobbs, and Craig Childs
discuss their book club selections at Colorado Water Congress. Photo by Alyssa Quinn
4. To celebrate their 10th anniversary, the Colorado Foundation for Water Education hosted two bike
tours along the South Platte River with Water 2012. Courtesy of the Colorado Foundation for Water Education

4
Now you may ask, “What does ‘Water
2012 related event’ mean?” With the
help of the Art Institute of Colorado,
Water 2012 created an overall look
including signature icons, a logo,

24

and marketing materials. These
elements were made available to all
Water 2012 partners to use as they
wished in accordance with Water
2012’s list of goals. “Plagiarism” was

literally the name of the game. So a
Water 2012 related event was an event
or activity that wasn’t specifically
executed by a committee but by a
partner organization that included

The Water Center of Colorado State University

the Water 2012 logo on a t shirt, flier,
or water bottle for example. And
there were hundreds of these events.
You may even have some Water 2012
paraphernalia that the Water 2012 key
players have never seen!
One of Water 2012’s major goals
was to expose 500,000 people to
its message. This was recorded
through feedback surveys, face
to face discussions, pictures, and
event materials. By September 2012,
the campaign was on the verge of
exceeding that goal, and a major
contributor to that success was media
exposure. Through the tireless work
of partners and volunteers, Water
2012 spawned a 52 week series of
articles in the Pueblo Chieftain and
the Valley Courier, a weekly series
that began in June in the Grand
Junction Free Press, and dozens of
other mentions in news articles, blogs,
and social media. In addition to the
news articles, Water 2012 was given
the opportunity to create a radio PSA
for the West Slope in June. Although
2012 had been declared the Year of
Water by Governor Hickenlooper,
the Senate, and communities all
over Colorado, Mother Nature had a
different plan for water, and the state
was dealing with a drought. In order
to recognize the drought and use it as
a learning opportunity, the PSA was
focused on the drought and how the
average Coloradan could understand
what was happening. The PSA played
6-10 times a day on four different
radio stations for the month of June.
A full list of article and blog mentions
is available on the Water 2012 website
(Water2012.org).
Though Water 2012 surpassed many
of its goals throughout the year, every
project has struggles. There were
parts of the state with little to no
involvement, finding funding for a
grassroots campaign was sometimes
difficult, and not all media channels
were interested in featuring a water
campaign when they could feature

a “sexier” topic. One major struggle
Water 2012 faced was reaching
the general public. The campaign
first aimed all its tools on reaching
the average Coloradan but several
months into 2012, it was clear that
the campaign was far more successful
reaching people already involved
in the water community and with
an initial interest in water. So the
campaign re-focused. It became
less about throwing messages to the
public and more about providing
educators, water conservancy
districts, and the like with materials to
give to their communities. The Water

2012 began like no other
year before, destined to be
a year of unprecedented
collaboration, volunteerism,
and educational efforts.
2012 Speakers Bureau presented to
leaders of communities such as at
Rotary Club meetings, Chambers
of Commerce, and Progessive 15
gatherings; the K-12 Committee, in
collaboration with CoCoRaHS, taught
teachers how to use rain gauges and
provided a lesson plan; one of the
six traveling educational displays
was made available to requesting
organizations for events such as
water festivals. With a campaign on
a limited schedule and with limited
resources, it was hard to make an
impact on people who knew little or
cared little about water. But hopefully,
through re-focusing campaign
efforts on providing the providers, an
impression was made on the general
public and will continue through the
developing Value of Water campaign
(coloradowaterwise.org/campaign).
In October 2012 an end of year survey
was distributed to more than 500
people to gauge overall impressions.
The responses collected were diverse

Colorado WaTer — JanUary/feBrUary 2013

from long time members of the water
community to average Coloradans
who had attended an event and taken
an interest in Water 2012. Generally
the opinions and impressions were
positive and appreciative. One
improvement suggested by several
survey takers was to reach outside
the water community but that was,
clearly, a struggle the campaign faced.
Others were concerned the campaign
was too focused on educators and
did not have a big enough reach or
deep enough connection. But with the
struggles came unexpected benefits
from the campaign. Through the
survey results it came to light that
many people felt that the campaign
allowed them to develop professional
relationships with people and
organizations they otherwise would
not have started. Water 2012 can only
hope that those people continue to
utilize those connections to create
more educational activities and
ongoing water stewardship.
2012 began like no other year
before; destined to be a year of
unprecedented collaboration,
volunteerism, and educational efforts.
On December 31, 2012 Colorado
Water 2012 will have come to an
end, but the good times don’t have to
end there. To keep the momentum
going and to celebrate a successful
Year of Water, Water 2012 will be
hosting a celebratory luncheon on
January 30, 2013 at the Marriott
Denver Tech Center. Lunch will be
$25 but the laughs and memories
are priceless! You can reserve
your spot at cowatercongress.org/
annualconvention. In conclusion,
Colorado Water 2012 would like
to send a huge thank you to every
person who volunteered their time
and efforts, those who financially
sponsored the campaign, and those
who attended an event. Without their
endless contributions and support
of Water 2012, none of it would have
been possible.

25

The WRECking Crew
Anne Casey, Youth Development Education Specialist,
Colorado State University Extension

C

olorado State University (CSU)
Extension and The Colorado
Water Institute are partnering with the
Colorado Water Conservation Board
to offer a unique new water education
program to high schools students called
the WRECking Crew, short for Water
Resource Education Curriculum Crew.
This program is designed to accomplish
two goals:
1. Reduce water usage at participating
schools through the streamlining of
their landscape irrigation system with
the use of LISA (Landscape Irrigation
Self Audit) Kits, a tool developed by
CSUE Water Resource Specialists and
to promote best practices for water
conservation for common activities
2. Provide a hands-on student-led STEM
(science, technology, engineering,
and math) enrichment project that
incorporates opportunity for skills
development, campus improvement,
and community service
Decreasing scores on international
tests of science and math competencies
(TIMSS and PISA) since the 1980s have
spurred a number of efforts to improve
education in the STEM areas. Studies
indicate that students learn more and
retain it longer when they are engaged
in real world experiential activities. In
addition, concerns about increasing water
consumption by a growing population
require fostering new consumption habits
in our communities. The WRECking
Crew provides a vehicle to accomplish
both objectives.
Designed as a weekly one hour, year-long
project, this program has been adopted
by three high schools in the Fountain
Creek/Arkansas River basins under
the leadership of: Nate Chisholm,
Environmental Science teacher at the
Air Academy High School in Colorado
Springs, Fran Weber, Honors Biology

32

teacher at Pueblo West High School in
Pueblo West, and Alec Walter, Biology
teacher at County High School/SEBS in
Pueblo. As an inter-curricular program, it
supports Colorado Academic Standards
in Science, Math, English, and History.
The program also has the additional
bonus of reducing the school’s water bill,
the savings on which the participating
students will be given partial authority
on how to re-allocate for other school
purposes.
During the course of the three years,
the program progresses from local
water issues to global ones. First-year
participants entering the program will
concentrate their attention on their own
campuses first. Using tools developed
by CSU Extension Water Resource
Specialists and climatologists, (LISA Kits,
Colorado Agricultural Meteorological
Network (CoAgMet), and Community
Collaborative Rain Hail and Snow
Network (CoCoRaHS)), students will
design experiments, collect and analyze
data, and finally implement a more
efficient water usage plan for their
schools. To date these students have
conducted a survey of student water
awareness, preformed a campus water
audit, and created a map of their school
grounds within their watersheds using
ArcGIS Online mapping software. They
will be encouraged to use these tools and
skills to audit their own homes, as well,
and bring awareness of water issues to
their neighborhoods.
In the second year of the program these
students continue their water education
by learning about the historical issues
concerning water in Colorado and the
Western Region of the U.S., including
water diversion projects, dams and
reservoirs, and irrigation systems. They
will study the natural history of native
plants and grasses and the ecosystems that
depend on them. Applying this knowledge
to the campus landscaping will allow

them to make good recommendations
for water-wise plantings and turf
grasses. The WRECking Crew teams
have visited demonstration xeriscape
gardens at the Colorado Springs Utilities
Conservation and Environmental Center,
2855 Mesa Road in Colorado Springs,
and the Southeastern Colorado Water
Conservancy District Xeriscape Garden,
31717 United Avenue in Pueblo, guided
by Perry Cabot, CSU Extension Water
Specialist. Field trips that are planned for
the future include a visit to the Arkansas
Valley Research Center to familiarize
students with agricultural water issues and
a camping trip to Lake Pueblo State Park
to learn about water diversion projects
and dams.
Third year participants will continue to
expand their research to include global
solutions to water problems. They will
study how other countries use water and
meet their water needs. Their studies
will focus on water technologies, how
they have changed and what is in store
for the future. At this point they will be
very familiar with their own campus
and be able to consider the possibility
of incorporating new technologies to
enhance their school’s environment.
While there is no formal program for
graduates of the program, they will be
expected to become teachers and record
keepers. In this way the program becomes
self-sustaining.
This program supports both water
conservation goals and educational
goals in STEM. Through experiential,
inquiry-based projects students will gain
valuable analytical skills and develop an
understanding of resource stewardship.
This program is sustainable, replicable,
and community-based. The desired
outcome of the program is to generate
greater interest in STEM careers with
links to water conservation, natural and
water resources management, watershed
studies, and climatology.

Lake Pueblo

Photo by Les Barstow

Throughout the program, teachers and
CSU Extension collaborators, Anne Casey,
CSU Extension Education Specialist,

Perry Cabot, CSU Extension Water
Specialist, and Shelby Will, CSU-Pueblo
Biology student intern, are using
feedback from teachers and students
to create a Colorado-specific water
education curriculum for use by high
schools throughout Colorado. Teachers
in the program attend two professional
development sessions each year, in
addition to participating in optional
curriculum writing sessions. This group
is combing the available literature for
best practices in water education to build
a curriculum that presents the best in
water conservation principles delivered
in the context of the research-based 4-H
extension Essential Elements of youth
development. The Essential Elements
of youth development form the basis of
all 4-H programs and include providing
opportunities that allow students to
see themselves as active participants in
the future as well as opportunities for
self-determination, mastery of a skill,
engagement in learning, and to value and
practice service to others.
One important benefit of the program for
schools is the increased awareness among
students of campus facilities issues. It
is hoped that through this exposure,
students will become more invested in
their campus buildings and grounds,
having developed a sense of ownership
and pride in their school’s appearance and
workings. Another hope is an increased
interest in STEM careers, especially in
the field of hydrology. According to the
Bureau of Labor Statistics, job growth in
that area is expected to grow by 18 percent
with many of those jobs being located in
Colorado, which has the highest average
annual wage in that profession at $94,670.
CSU Extension is excited to be partnering
with these outstanding students and
teachers on the WRECking Crew through
the generous support from the Colorado
Water Conservation Board. We look
forward to seeing how these students
“wreck” old out-dated water systems on
their campuses and bring in their own
fresh water-saving ideas.

33

Colorado Water Conservation Board
2012 Drought Conference
Taryn Finnessey, Drought and Climate Change Specialist, State of Colorado

T

he 2012 Colorado Water
Conservation Board (CWCB)
State Drought Conference: Building a
Drought Resilient Economy Through
Innovation was held September 19 and
20 in Denver. This two-day conference
highlighted the most innovative
approaches to drought preparedness
and brought attention to how those
innovations contribute to an economy
more resilient to the devastating effects
of this natural disaster. Although
drought has a much slower onset
than other natural disasters, it still
brings economic consequences that
can devastate a community. In 2012,
nearly every county in Colorado was
designated as a primary disaster area
for drought, and the wildfire season
proved to be the most costly in history.
The agricultural as well as the tourism
and recreation industries, the first
and second largest contributors to
Colorado’s economy, respectively, are
impacted deeply by drought as are
natural environments, municipalities,
and local businesses. A goal of the
conference was to put forth an agenda
that would help communities address
drought concerns in new and efficient
ways. Representatives from a multitude
of industries presented, including
finance, recreation, development,
energy, agriculture, and emergency
management; all offered different
views of how they are impacted by
drought and how they are able to
address those concerns.
While it was a Colorado drought
conference, presenters from other
western states also talked about their
recent experiences with the impacts
of drought as well. Representatives
from ski areas and the energy sector
discussed their approaches to drought
response, while environmental
representatives presented mechanisms

to adapt to drought and climate change
yet still protect our natural resources.
Innovations on the business side were
also examined from Colorado’s unique
beer brewing industry to agricultural
range management in the San Luis
Valley.
In addition to more than forty
presenters, the conference attendees
also heard from three keynote
speakers. Entrepreneur and
philanthropist John Paul DeJoria spoke
about his investments in sustainability
through his companies Paul Mitchell
Hair Systems and Patrón Spirits, as
well as his involvement domestically
and abroad in advancements to help
less developed regions gain improved
access to clean water and nutrition.
Author and Colorado resident Steve
Maxwell spoke about his recent book
The Future of Water, in which he looks
at major challenges facing our water
resources in the decades to come and
empowers us to change the future of
water. Last, but certainly not least,
Governor John Hickenlooper spoke
about how his administration is trying
to address challenges to ensure that
generations of future Coloradoans
can both enjoy the natural beauty of
Colorado and maintain a high quality
of life with adequate water availability.
United States Secretary of Agriculture
Tom Vilsack and Colorado
Commissioner of Agriculture John
Salazar were on hand the second
day of the conference to announce
the creation of a new Colorado
conservation project. The project will
enhance water quality, reduce erosion,
improve wildlife habitat, and conserve
energy in portions of the Rio Grande
watershed within Colorado. Secretary
Vilsack said the “USDA is proud to
work with the state of Colorado to
enroll up to 40,000 acres of eligible

Colorado WaTer — JanUary/feBrUary 2013

irrigated cropland in an effort to
address critical water conservation
and other natural resource issues
within portions of the Rio Grande
watershed.” The program is part of the
Conservation Reserve Enhancement
Program (CREP), in which
participants will receive compensation
and incentives for voluntarily enrolling
irrigated cropland into contracts and
installing the approved conservation
practices.
Feedback on the conference has been
extremely positive and CWCB feels
that the event was successful in raising
awareness about the importance
of taking an innovative, proactive
approach to drought preparedness
as a means to build a more drought
resilient economy. Conference
evaluations show that attendees
overall were very satisfied. Average
overall satisfaction ranked 4.43
out of five; the conference also met
advertised objectives (4.26). Drought
Connections to our Larger Economies,
Vulnerability and Economic Impacts:
Urban Environments, and Role of
Water & Technology in Agricultural
Production were among the highest
rated presentations. More than half of
the evaluation respondents said that
they would like to see a state drought
conference convened every two to
three years. Local and regional topics
were the most recommended additions
for future events.
If you were unable to attend the
conference but are interested in
learning more, presentations as well
as audio are available on the CWCB
website at:
http://cwcb.state.co.us/watermanagement/drought/Pages/2012CW
CBStatewideDroughtConference.aspx

37

PRESENTED IN CONJUCTION WITH HYDROLOGY DAYS AT CSU

D ET AILS AT h t t p : //h y d r ol ogy d a y s . c ol os t a t e . e d u

WATER &
WATER CAFÉ

MARCH 22-23, 2012

SUSTAINABILITY

THURSDAY EVENT

FRIDAY EVENT

MEETING THE

GLOBAL CHALLENGES OF

WATER SCARCITY

WATER SUSTAINABILITY
IN THE
21ST CENTURY

WHY THE WORLD NEEDS WHAT CSU HAS

MARCH 22 - 5:00PM

MARCH 23 - 10:00-12:00PM
CHEROKEE PARK BALLROOM, LSC

NORTH BALLROOM, LORY STUDENT CENTER

KEYNOTE SPEAKER

BRIAN RICHTER

Global Fre s hw ate r S trate gi e s
The Nature Cons e rvanc y

BRIAN RICHTER

Gl ob a l F r es h w a t er S t r a te gie s
T h e N a t u r e Co n s er v a n cy

FACULTY PANELISTS

LEROY POFF

DE PART M E NT OF B I OL OG Y

KURT FAUSCH

D EPARTMEN T O F FISH, W I L DL I F E , AND C ONSE RV AT I ON B I OL OG Y

BRIAN BLEDSOE

D EPAR TMEN T O F C I V I L AND E NV I RONM E NT AL E NG I NE E RI NG

GENE KELLY

D E PART M E NT OF SOI L AND C ROP SC I E NC E S

The Colorado State University Water Café is
an interdisciplinary, interactive series
designed to examine critical water issues
and the University's roles in their solutions.

s p o ns o rs
Colorado State University

W AT E R C E N T E R

www.sustainability.colostate.edu

Fall 2012 Theme: Addressing Global Water Resource Challenges with Local Expertise
Mondays at 4:00 PM, Building NATRS 109
Aug 20

John Stednick
Erin Donnelly

Environmental Flows; Or Can Groundwater Pumping Grow More Sturgeon?

Aug 27

Susan De Long
Jeremy Chignell

Energy Recovery From Wastewater: New Trends and Possibilities

Sept 10

Brian Bledsoe
Joel Sholtes

River Management in a Changing Climate: Tools for Planning
Under Uncertainty

Sept 17

Larry Roesner
Sybil Sharvelle

Integrated Urban Water Management

Sept 24

Kurt Fausch
James Roberts

Ecological Futures for Native Trout of the Interior West in a Changing
Climate: Are We in Hot Water Yet?

Oct 1

Patty Rettig

Using the Water Resources Archive for Research, Teaching and Scholarship

Oct 8

Patrick Byrne
Steve Becker

Improving Drought Tolerance in Great Plains Wheat Cultivars with Synthetic
Hexaploid Wheat

Oct 15

Allan Andales
Addressing Water Scarcity Through Limited Irrigation Cropping: Field
Neil Hansen
Experiments and Modeling
Kendall DeJonge

Oct 22

Susan De Long
Maria Renno

Development of Sustainable Water Treatment Technologies

Oct 29

William Bauerle
Grace Lloyd

Measurement and Modeling of Physiological Responses to Soil Moisture Deficits:
Applications to Irrigation Scheduling, Plant Breeding, and Global Climate Models

Nov 5

Mark Fiege

Using Digital History for Education About Local Water Resources

Nov 12

Melinda Laituri
Faith Sternlieb

Spanning Boundaries Across the Colorado River Basin: A Geospatial
Analysis of Agricultural Water Governance

Nov 26

Jorge Ramirez

Vulnerability of US Water Supply to Hydroeconomic and Climate Variability

Dec 3

LeRoy Poff

Using Environmental Flows to Stem Species Invasion of Western Rivers
in a Period of Rapid Climate Change

Students wishing to obtain 1 credit for the seminar may sign up for
Water Resources Seminar (CRN 67067) GRAD 592 Section 001. The Fall 2012 seminar will be
held Monday afternoons at 4-5pm in Natural Resources Room 109.

Faculty and guests are welcome to attend and participate.
For more information, contact Reagan Waskom at [email protected] or visit the CWI website. Sponsored
by CSU Water Center & School of Global Environmental Sustainability

Newsletter of the Water Center of Colorado State University
March/April 2012

Volume 29, Issue 2

Newsletter of the Water Center of Colorado State University

Newsletter of the Water Center of Colorado State University

May/June 2012

July/August 2012

Volume 29, Issue 3

Theme: Student Research

Theme: Horticulture

Co-Sponsored by Colorado Water Institute, Colorado State University Agricultural Experiment Station,
Colorado
StateWUniversity
Extension,
Colorado State Forest Service, and Colorado Climate Center
Colorado
ater — MarCh
/april 2012

I

Colorado Water
Volume 29, Issue 2
Horticulture

Co-Sponsored by Colorado Water Institute, Colorado State University Agricultural Experiment Station,
Colorado
ater — MayExtension,
/June 2012Colorado State Forest Service, and Colorado Climate Center
Colorado
StateWUniversity

Colorado Water
Volume 29, Issue 3
Student Research

Volume 29, Issue 4

Theme: Groundwater

I

Co-Sponsored by Colorado Water Institute, Colorado State University Agricultural Experiment Station,
Colorado
aTer — JUlyExtension,
/aUGUST 2012
Colorado
StateWUniversity
Colorado State Forest Service, and Colorado Climate Center

Colorado Water
Volume 29, Issue 4
Ground Water

Newsletter of the Water Center of Colorado State University

Newsletter of the Water Center of Colorado State University

Newsletter of the Water Center of Colorado State University

September/October 2012

November/December 2012

January/February 2013

Volume 29, Issue 5

Theme: Energy and Water

Co-Sponsored by Colorado Water Institute, Colorado State University Agricultural Experiment Station,
Colorado
ater — September
/oCtober
2012State Forest Service, and Colorado Climate Center
Colorado
StateWUniversity
Extension,
Colorado

Colorado Water
Volume 29, Issue 5
Energy and Water

Volume 29, Issue 6

Theme: Colorado River

I

Co-Sponsored by Colorado Water Institute, Colorado State University Agricultural Experiment Station,
Colorado State University Extension, Colorado State Forest Service, and Colorado Climate Center

Colorado Water
Volume 29, Issue 6
Colorado River

Volume 30, Issue 1

Theme: Water Education

Co-Sponsored by Colorado Water Institute, Colorado State University Agricultural Experiment Station,
Colorado State University Extension, Colorado State Forest Service, and Colorado Climate Center

Colorado Water
Volume 30, Issue 1
Water Education

I

Other Colorado Water Institute Research and
Activity Reports

CSU Water Scientists Part of Key State Agency Trio
Answering Some of Colorado’s Big Water Resource Questions
Denis Reich and Perry Cabot, Extension Water Resources Specialists, Colorado Water Institute
Allan Andales, Soil and Crop Sciences, Colorado State University
Timothy Gates, Civil and Environmental Engineering, Colorado State University

B

y the time this is printed,
Colorado’s 1177-Roundtable
process will be digesting the second
of its now annual state summits held
in the Denver area on March 1. The
summit convenes some of the best
water minds in the state to collectively
review the challenge of meeting
Colorado’s future water demand.
Since the initial summit in 2011,
the phrase “four-legged stool” has
become somewhat of a catch phrase
at Roundtable meetings in Colorado’s
various river basins. It’s a term coined
to describe the four strategies that
most regional water leaders agree are
needed to address the state’s future
municipal water deficit or “gap”: New
Supply, Conservation, Agricultural
Transfers, and Identified Projects and
Processes. The Roundtables’ current
philosophy subscribes to a balanced
contribution from all four “legs” so
all Coloradans can enjoy a safe and
reliable water supply in perpetuity.
There’s also a three-legged stool
working on the objective of secure
water resources for all Coloradans,
now and into the future. It’s perhaps
not obvious to the water community,
but its significance and contribution
is real. It’s the relationship between
three of the state’s institutions that
are most directly focused on waterrelated investigations: the Colorado
Water Conservation Board (CWCB),
the Colorado Department of Public

Health and Environment (CDPHE),
and Colorado State University
(CSU).1 As questions continue to be
asked of the state’s water supply and
quality, this relationship will continue
to play a role in the major water
concerns for Colorado.
A major metric for the strength of this
relationship is the number and value
of projects that CSU staff and faculty
are seeing sponsored by CWCB and
CDPHE. At the time of writing, CSU
was under contract with CWCB for
11 current projects for a total value
of $1,017,659, with at least three
additional projects pending. With
CDPHE’s Water Quality Control
Division (WQCD), CSU principal
investigators (PIs) account for one
project under contract for $501,735
with one project pending.2 CDPHE
also funds the state nonpoint
source (NPS) pollution program
coordinator through the Colorado
Water Institute at CSU. Together this
is about 16 percent of the combined
annual budget of the Roundtable
process ($7 million3) and the
state’s NPS allocation ($2 million4).
None of these figures account for
the many additional CWCB and
CDPHE sponsored projects that
CSU staff partner on as Co-Principal
Investigators or the completed
work that these three agencies have
collaborated on in the past. The
financial weight of such a healthy list

of projects is strong evidence that this
three-agency relationship is engaged
and productive.
“The Colorado Water Conservation
Board and Colorado State University
enjoy a very positive relationship
with each other,” remarks Todd
Doherty of the Colorado Water
Conservation Board. Doherty
manages two grant programs than
have seeded partnerships with CSU
personnel on numerous projects, such
as the Roundtables’ Water Supply
Reserve Account and the Alternative
Agricultural Water Transfer Methods
program. “This relationship,” he adds,
“has helped bring the CWCB together
with researchers and academics on
water resource management issues
that otherwise might not have
occurred.”
A good case study for some of this
work is the Lower Arkansas River
Valley where a number of programs
have benefited from CWCB and
CDPHE support. If there were a state
scale for water scarcity and quality
concerns (think the travelers alert we
hear at airports), the Lower Arkansas
probably would show up as dark
orange. This is a region wrestling
not only with the side-effects of
irrigated land dry-up or “buy and
dry” and river compact obligations
with Kansas, but also with serious
water quality concerns—especially

1. Projects funded by CWCB often involve cooperation with the Colorado Division of Water Resources (CDWR). The Division of Wildlife and State Parks also has a significant role in state water due its broad aquatic life and water-based recreational interests, but its
scope is relatively narrow.
2. Source: Colorado State University Office of Sponsored Programs.
3. CWCB. Oct 2011. “Water Supply Reserve Account Annual Report.” DNR Report to the respective House of Representatives and Senate committees for Colorado’s consumptive and non-consumptive water needs.
4. 2011NPS Colorado 319 program funding announcement: http://npscolorado.com/2011%20Announcement.pdf

16

The Water Center of Colorado State University

Figure 1. The AgLet EZ software user interface for optimizing the use of irrigation water leasing.

salinity and selenium. CSU, CWCB,
and CDPHE have been cooperatively
seeking to answer the challenging
questions these problems present for
a number of irrigation seasons, and
they’re starting to bear fruit.
In an attempt to alter the historic
trends towards “buy-and-dry,” and
instead to support strategies to keep
agriculture viable, several fallowing
and leasing projects centered at the
Rocky Ford Research Center have
been commissioned. Since 2009, this
CWCB-funded $92,000 three-year
project has explored the profitability
and stewardship potential of cropping
systems that fallow proportions
of land to incorporate potential
water leasing arrangements. Such
lease-fallow arrangements allow
temporary water transfers to be
controlled by the water rights holders
in the Lower Arkansas Valley, thus
helping satiate the growing thirst
of front-range municipalities while
preserving productive irrigated

land. Mike Bartolo and Jim Valliant,
research scientists at the Rocky Ford
Agricultural Experiment Station,
have been the primary partners
working through CWCB’s Alternative
Agricultural Water Transfers Methods
Program5 to host this critical
research. An important product of
the study has been an Excel®-based
lease-fallow simulator, developed in
coordination with Harvey Economics
and James Pritchett. This Agricultural
Leasing Evaluation Tool, known
as “AgLet,” is an irrigator-focused
software program that optimizes
crop and fallow mixes based on
market prices for leased water and
commodities. Under the supervision
of Perry Cabot and Caleb Erkman,
the project team is developing an
“EZ” version (Figure 1) that includes
a user-friendly platform.
At the conclusion of the Colorado vs.
Kansas litigation6 on the Arkansas
River compact, the Special Master
accepted a new method for calculating

potential evapotranspiration (ET)
in the computer model that is used
to determine compact compliance.
This new method involves the use
of the Penman-Monteith equation.
The resulting Penman-Monteith
reference (potential) ET number is
then multiplied with a crop coefficient
for the ET of a specific crop. To better
understand more precisely the implications of using this new ET method
for determining compact compliance,
CWCB funded the installation and
operation of two precision weighing
lysimeters7 at Rocky Ford.
Allan Andales of CSU’s Soil
and Crop Sciences has led the
project partnering with other CSU
personnel, the Arkansas Valley
Research Center, and the Colorado
Division of Water Resources. A
four-year $375,000 project has been
supporting the day-to-day operation
and maintenance of one large
and one small reference weighing
lysimeter for determining local
crop coefficients and for comparing
physically-measured local ET to
Penman-Monteith ET calculations
(Figure 2). 2011 was the first year of
simultaneous measurement of alfalfa
ET on both lysimeters. This data will
begin the process of formulating
Lower Arkansas Basin crop coefficients that will improve consumptive
use estimates that are used to ensure
compact compliance. Better estimates
of crop consumptive use can also
help improve local irrigation water

5. http://cwcb.state.co.us/LoansGrants/alternative-agricultural-water-transfer-methods-grants/Pages/main.aspx
6. Montgomery, D. Oct 2003. “Lessons Learned from the Arkansas River Case.” Keynote Presentation – South Platte River Forum.
http://wsnet.colostate.edu/cwis31/ColoradoWater/Images/Newsletters/2003/CW_20_6.pdf
7. A lysimeter is a means of precisely quantifying crop water use by accounting for weight changes in a known mass of soil (a “monolith”) growing a specific crop.

Colorado Water — March/April 2012

17

Figure 2. A view at the Arkansas Valley
Research Center of the large lysimeter and
associated sensors.

management, such as irrigation
scheduling.
Timothy Gates of CSU’s Civil
and Environmental Engineering
Department will this year conclude
a $501-thousand dollar 3-year phase
of research targeted on selenium and
salt fate and transport in the Lower
Arkansas River Valley, with 40 percent
matching funds provided primarily
by the Colorado Agricultural
Experiment Station at CSU. The local
Pierre shale soils are rich in selenium
and salts that, upon contact with
irrigation water, dissolve and concentrate in the groundwater aquifer
and flow into the Arkansas River.
Apart from the salinity challenge
this presents for eastern plains and
Kansan irrigators, there are aquatic
life implications as well. Selenium is
essential for most forms of life, even
humans, but each species usually has
an acceptable range of concentrations
for healthy intake. Outside this range
selenium can become particularly
disruptive to physical development.
Fish are highly sensitive to the

slightest increases above background
selenium levels. Scientists from the
United States Department of the
Interior are on record attributing
population problems for a number
of fish species in Colorado to above
normal selenium concentrations in
fish habitat reaches.8
The work of Gates and his team is
aimed at reaching an understanding
of the physical and chemical processes
that influence salt and selenium
mobilization. The resulting data are
essential for designing agricultural
best management practices (BMPs)
that potentially reduce or eliminate
contaminant loading. “We have
enjoyed a long and productive
relationship with Gates in the Lower
Arkansas and a number of other CSU
faculty,” says Greg Naugle, Restoration
and Protection Unit Manager at
CDPHE’s Water Quality Control
Division. “Dr. Gates’ work,” Naugle
continues, “will allow for large-scale
and cost-effective remediation of
selenium concerns.”

Results of related work (some funded
prior to this CDPHE project) suggest
that groundwater salt movement and
accumulation is inflicting damage on
some agricultural ground, evidenced
by water logging and high salt levels
in otherwise productive soils. More
recent determinations confirm the
long held suspicion that nitrogenbased fertilizers have the potential
to chemically accelerate selenium
loading rates and slow compliance
progress for the Arkansas river with
the state selenium standard (4.7
ppb) – posing another challenge for
the CSU and CDPHE partnership to
address in their pursuit of preserving
Arkansas Valley agriculture and
mitigation for selenium pollution.
All of these projects provide a
foundation for relevant work in
other river basins around the state.
For example, fallowing schemes are
very much a part of the picture in the
South Platte and Republican River
Basins, and selenium is already a big
piece of a Programmatic Biological
Opinion for endangered fish species
recovery in the Lower Gunnison River
Basin. The less obvious component
is the relationships that develop
between staff members from these
agencies as a result of these projects.
This often results in informal problem
solving outside of the scope of specific
projects, adding value to the overall
service that CWCB, CDPHE, and
CSU are tasked with providing to the
state’s water-using community.

8. Lemley, DA. 1987. “Aquatic Cycling of Selenium: Implications for Fish and Wildlife.” US-DOI Fish and wildlife Leaflet 12: http://www.
cerc.usgs.gov/pubs/center/pdfDocs/90562.PDF. Also: Hamilton, SJ; et al. 2002. “Toxicity of selenium and other elements in food
organisms to razorback sucker larvae.” Aquat Toxicol. 2002 Sep 24;59(3-4):253-81.
9. Gates, T., Garcia, L., and Labadie, J. 2006. “Toward Optimal Water Management in Colorado’s Lower Arkansas River Valley: Monitoring and Modeling to Enhance Agriculture and Environment.” CWI Report: 205. CSU AES: TR06-10.Morway, E., and Gates, T. 2012.
“Regional Assessment of Soil Water Salinity Across an Intensively Irrigated River Valley.” Journal of Irrigation and Drainage Engineering, 138(5): In Press.
10. Gates, T. et al. 2009. “Assessing Selenium Contamination in the Irrigated Stream-Aquifer System of the Arkansas River, Colorado.”
Journal of Environmental Quality, 38:2344-2356. Bailey, R., Hunter, W., and Gates, T. 2012. “The Influence of Nitrate on Selenium in
Irrigated Agricultural Groundwater Systems.” Journal of Environmental Quality, 41:In Press.

18

The Water Center of Colorado State University

Twin Lakes Reservoir.

Photo by Bill Cotton

Variables Controlling Basin Scale Sediment
Yields to Reservoirs in Dry Lands of the
Western U.S. and Central Turkey
Umit Duru, Ph.D. Candidate, Geosciences,Colorado State University
Faculty Advisor: Ellen Wohl

Introduction
Reservoirs around the world
experience problems with sediment
filling, which results in loss of storage
capacity and operating potential.
Sediment accumulation in reservoirs
has environmental and economic
consequences, especially in semiarid
regions where reservoirs were mostly
built for irrigation and water supply,
as well as generating electricity or
flood control. In some cases, the
sediment delivery is large compared
with the reservoir capacity, and
reservoir capacity and useful life
are depleted faster than planned.
Also, in many regions, reservoirs
have already been constructed in
the most desirable areas. If these
existing reservoirs completely fill with
sediment, new reservoirs would be
constructed in less desirable and more
expensive areas.

Sediment input to reservoirs likely
reflects several potential controls
(e.g., drainage area, relief, lithology,
land use, disturbances such as fire
or deforestation) on basin-scale
sediment yields in arid and semiarid
regions. The smallest sediment
particles may not be kept within
the reservoir for a long time,
but may instead be discharged
downstream without settling in the
reservoir. Larger particles may be
retained in a reservoir, depending
on how completely suspended
sediment settles out in the reservoir.
Furthermore, during peak flow
seasons, inflowing water with huge
volumes of sediment can enter a large
reservoir and not be subsequently
disturbed. To overcome the effect
of sediment deposition, a portion
of the volume is reserved for
sediment storage in large reservoirs,
which requires extra volume for

Colorado Water — May/June 2012

the reservoir and increases the
construction expenses.
Sediment accumulation also occurs
throughout the reservoir. As the
useful storage capacity starts to be
depleted, the reservoir becomes
insufficient to maintain the intended
purposes. For example, 600,000 cubic
meters of sediment have filled Strontia
Springs Reservoir in Colorado, in
large part due to the 2002 Hayman
Fire and, to a lesser extent, the 1996
Buffalo Creek Fire. The fires scorched
the vegetation on the land upstream
from the reservoir.
Previous work in the western U.S.
and central Turkey thus suggests that
topography, land cover, and disturbances such as wild fire influence
sediment yield, but it remains unclear
how the relative importance of these
factors varies at temporal and spatial
scales that are particularly relevant
to reservoirs in the region, namely

7

50-100 years and 1,000-7,000 km2,
respectively. The primary objective
of my work is to assess the relative
importance of several potential
control variables in terms of influence
on sediment yield in the specific study
areas. Potential control variables
include lithology, topography, land
cover, land use, and disturbance
history. A second objective is to
develop a sediment yield model based
on statistical analyses of correlations
among the potential control variables
and sediment yield. The final objective
is to evaluate regional differences
in correlations between potential
control variables and sediment yield
among Colorado, other portions of
the western U.S., and central Turkey.
These objectives will be evaluated by
testing the following hypotheses:

1. Sediment yield correlates most
strongly with disturbance history,
and to a lesser extent with
lithology, topography, land cover,
drainage density, and land use.

and disturbance for each reservoir
and for the entire set of reservoirs,
and (ii) average sediment input and
all control variables for the entire set
of reservoirs.

2. The relative importance of
potential control variables will be
consistent among diverse arid/
semiarid regions of moderate to
high relief (the Colorado Front
Range, other portions of the
western U.S., and the Central
Anatolian Plateau of Turkey

3. Sediment yield will not be evenly
spread across the contributing
basin upstream from a reservoir.
This hypothesis is based on the
fact that it might be possible to
identify which tributary potentially brings more sediment input
to the reservoirs based on variable
characteristics such as land cover,
natural disasters, and topography
in the basin.

Hypotheses 1 and 2 will be tested by
statistically evaluating correlations
among (i) sediment input and
temporally variable control variables
(land cover, disturbance), either at
annual intervals or averaged over
time intervals dictated by the availability of information on land cover

4. A correlation exists between
reservoir size or shape and
volume of sediment accumulated
per year (i.e., total sediment
volume normalized by time
interval of accumulation).

Study Location
The research focuses on the Colorado
Front Range, other sites in the arid/
semiarid portions of the western U.S.
for which suitable reservoir data are
available, and the Central Anatolian
Plateau of Turkey (Figure 1).

Locations of selected reservoirs in the U.S. and Turkey.

8

First, three reservoirs (Halligan,
Cheesman, and Strontia) that have
the most available data were selected
for study in the Front Range. Second,
I used the Reservoir Sedimentation
Information System (RESIS) II
database of the Army Corps of
Engineers, Bureau of Reclamation,
and U.S. Geological Survey to choose
additional reservoirs that met three
criteria: arid or semiarid climate,
mountainous or hilly terrain, in the
western United States. From this
database, I identified 16 additional
reservoirs that met these criteria.
Third, I have selected reservoirs in
Turkey for which suitable sedimentation data are available and which are
comparable to those in the western
U.S. based on climate, topography,
and drainage area.

The Water Center of Colorado State University

Reservoirs across the United States
Halligan Reservoir, CO

Cascade, ID

Prineville, OR

Cheesman Lake, CO

Caballo, NM

Thief Valley, OR

Strontia Reservoir, CO

El Vado, NM

Unity, OR

Paonia, CO

Altus, OK

Warm Springs, OR

Anderson Ranch, ID

Agency Valley, OR

Starvation, UT

Arrowrock, ID

Bully Creek, OR

Black Canyon, ID

Ochoco, OR

Blue Mesa Reservoir.

Photo by Bill Cotton

Reservoirs across Central Turkey
Hirfanli, Kirsehir

Cayoren, Balikesir

Cubuk 1, Ankara

Kesikkopru, Ankara

Doganci, Bursa

Cubuk 2, Ankara

Bayindir, Ankara

Hasanlar, Duzce

Demirkopru, Manisa

Some of the reservoirs listed above
have limited data on reservoir
operations and sedimentation over
time. Numerous conversations with
water resource managers and requests
for information have indicated that
data on sediment yield or patterns
of sediment accumulation within
reservoirs since the time of reservoir
construction are very limited. These
conversations also indicate that we
are not likely to receive permission
to conduct bathymetric surveys
of reservoirs for which original
bottom topography data (i.e., bottom
topography at time of reservoir
construction) are available. To date,
I have been able to obtain data for
nine reservoirs and 1:250.000 scale
digital maps for these reservoirs in
central Turkey, three reservoirs in
Colorado, and 10 reservoirs in the
western U.S. Climate and hydrologic
conditions are similar within the

regions in which these reservoirs are
located. I am continuing to contact
water resources managers in an effort
to identify additional reservoirs for
which either (i) sedimentation data
over time are available or (ii) original
bottom topography data are available
and bathymetric surveys will be
permitted.

Method
For each reservoir chosen for
inclusion in this study, I will complete
the following analyses:
1. I will characterize variables
potentially influencing sediment
yield, including catchment
geology, drainage area,
topography, annual precipitation,
land cover and disturbance
history, history of reservoir
construction and operation,
and initial bottom topography

Colorado Water — May/June 2012

and subsequent sediment
accumulation.
2. I will use GIS software to
characterize the variables and
to statistically evaluate correlations between potential control
variables and sediment yield via
stepwise linear regression and
other statistical approaches.
3. I will undertake these analyses
for each reservoir individually,
and then for progressively larger
subsets of all of the reservoirs
(i.e., Colorado Front Range, other
sites in western U.S., Turkey, and
all sites combined). Most of the
empirical erosion rate approaches
are based on the universal soil
loss equation (USLE), MUSLE
(modified USLE), sediment yield
as a function of drainage area,
and sediment yield as a function
of drainage characteristics.

9

Large Aperture Scintillometers for
Evapotranspiration Evaluation
Evan Rambikur, MS Candidate, Civil and Environmental Engineering, Colorado State University
Faculty Advisor: José L. Chávez

Introduction
How do we effectively manage
application of irrigation water for
crop production in arid and semi-arid
environments? One of the primary
inputs necessary for knowing
appropriate timing and amounts of
irrigation is actual evapotranspiration
(ET). For practical applications, ET
can be estimated using a reference
ET value (e.g., alfalfa, ETr) and a crop
coefficient (Kc).The value of ETr is
computed using weather data from
a local standard weather station, and
Kc values for different crop types
are published in the literature. On a
research basis, different methods for
estimation/measurement of actual
ET have emerged including scintillometry, which uses electromagnetic
radiation transmission to capture
information on the turbulence in the
atmospheric boundary (near-surface)
layer. For the specific case of the
large aperture scintillometer (LAS),
estimates for the surface sensible heat
flux can be obtained for representative
path lengths up to 4.5 km (2.8 mi.).
Sensible heat flux (energy) occurs as
a result of air temperature gradients
between the land surface and some
height within the boundary layer (e.g.,
two m). Since ET is also a process
that uses available energy at the land/
crop canopy surface, researchers
can take advantage of a land surface
energy balance in conjunction with
LAS measurements to indirectly
estimate (vegetative) ET rates. Thus,
ET estimates using an LAS are
Image 3. LAS 1 receiver at the dry grassland
site, along with net radiometer (left) and ancillary
sensors and data collection equipment.

Photo by Evan Rambikur

14

obtained from LAS sensible heat flux
(H) and ancillary measurement of net
radiation (Rn) and soil heat flux (G).
In this study, LAS technology was
tested at two different locations in
the Arkansas Valley, Colorado. Three
LAS systems (LAS model, Kipp and
Zonen B.V., Delft, The Netherlands)
were deployed during the 2011 study
period. An LAS system operates by
emitting a near-infrared light beam
from a transmitter to a receiver, which
is set up at least 250 m (820 ft) away.
The transmitter and receiver have the
same aperture diameter and must
be aligned with each other. For the
optimum (performance evaluation)
case study, the LAS should be set up
over a horizontally uniform terrain at
least 1.5 m (five ft) from the ground
or crop canopy surface. It is worth
noting that the Kipp and Zonen LAS
has been criticized in the literature
for having issues with inter-sensor
variability and inherent (design)
biases. This study tested the performance of the Kipp and Zonen LAS
for predominantly dry and irrigated
surfaces in order to more comprehensively evaluate the LAS method
of ET estimation. The evaluation of
the LAS results was performed using
concurrent heat flux measurements
made with an Eddy Covariance
system at both the dry and irrigated
sites. The Eddy Covariance (EC)
instrumentation consisted of a
3D sonic anemometer (CSAT3,
CSI, Logan, UT) and a krypton
hygrometer (KH20, CSI, Logan, UT).

The 3D sonic anemometer provides
information on wind speed in three
orthogonal directions (i.e., x, y, and
z), as well as sonic (air) temperature,
and vapor pressure is measured by
the hygrometer. The EC system yields
direct estimates of sensible heat and
ET fluxes.

Field Campaign
During the 2011 summer, a
short-term experiment was conducted
with three LAS units operating over a
uniform, dry grassland area in order
to assess the LAS inter-sensor consistency. Following this experiment, two
of the LAS units were removed with
one of them (LAS 2) being re-located
to the Colorado State University
(CSU) Arkansas Valley Research
Center (AVRC), while one unit (LAS
1) remained at the grassland site (LAS
3 was moved to another location near
Iliff, CO). The EC instrumentation
was also set up at the grassland site
for some time, overlapping the period
of the LAS inter-comparison study.
Eventually, the EC instrumentation
was moved to the AVRC, providing
a reference for LAS 2. At both sites,
sensors were installed to measure air
temperature, relative humidity, and
horizontal wind speed. These sensors
were necessary for processing the LAS
data. At the dry grassland site, soil
water content sensors were installed at
two locations in the near surface soil
along with soil temperature sensors
and soil heat flux plates, in order to
capture the heat flux into the soil (G).

This misalignment is assumed to have
occurred due to strong, stormy winds,
which caused a physical shift in the
alignment of the transmitter and/or
receiver.

LAS to EC Comparison

(Left to right) Abhinaya Subedi, Stuart Joy, and Mcebisi Mkhwanazi measure the height of a LAS
transmitter tripod at the dry grassland site.

Photo by Evan Rambikur

Net radiation (Rn) sensors were also
installed at the same two locations on
site. At the AVRC, LAS 2 was installed
with a path length spanning two
irrigated alfalfa fields. There were four
available stations for measurements
of Rn and G at the AVRC. In addition,
eight soil water content sensors (ACC,
TDT, Acclima, Inc., Meridian, ID)
were installed at four depths and two
locations during the study period.
These were installed to estimate ET
from two neighboring corn fields
south of the LAS path. Unfortunately,
the data from these sensors were
unreliable, and therefore no further
analysis with these data was made.
The alfalfa in both fields was
harvested about three weeks following
the LAS installation, and reached a
height of approximately 40 cm (16 in)
near the end of the study period. Due
to the nature of the surface (furrow)
irrigation timing for both alfalfa
fields, the alfalfa growth conditions
were generally not homogeneous.

Results
Data were collected periodically
from both sites and processed using
standard algorithms in order to

obtain time series flux estimates. The
data were processed to produce 30
minute averages of sensible heat (H)
and evaporative heat (ET) flux. For
the LAS inter-comparison, the H
fluxes were compared and for the LAS
to EC comparison, both H and ET
fluxes were compared.

LAS Inter-comparison
In regard to LAS consistency, based
on the results observed at the
grassland site, it is considered that
the deviation in H between LAS units
is dependent on inherent bias and
conditional bias. For part of the study
when the LAS units were well aligned,
the mean bias deviation, normalized
by the mean absolute value of the
LAS H reference (MBE/|Ō|), ranged
between six and 11 percent. This
relative deviation corresponds to the
assumed inherent bias. After a slip in
alignment, the scatter and deviation
in H increased between the LAS units.
The estimated misalignment-induced
error increased the mean bias to
a maximum observed value of 24
percent (MBE/|Ō|). Note that LAS
2 almost completely lost alignment
for approximately half of the study.

Colorado Water — May/June 2012

At the dry grassland site, the sensible
heat flux (H) obtained with the
LAS correlated fairly well with the
corresponding H obtained with the
EC system. It was observed that the
H from each LAS was approximately
equal to or larger than the H from the
EC. The coefficient of determination
(r2; for the linear regression of LAS
to EC H) was better than 0.9 for all
LAS units. Further, the ET derived
from the LAS was consistently larger
than the ET from the EC for the study
period at the dry grassland site. At
the AVRC site, H from the LAS was
generally larger than H from the EC.
However, the correlation between
LAS and EC H values was not as
consistent as was observed for the
dry grassland site. Furthermore, at
the AVRC, the magnitude of the ET
derived from the LAS was generally
similar to that of the EC system,
albeit with some observed scatter.
For the AVRC site, the heterogeneous
surface conditions (crop type, growth,
surface wetness) must be considered
for appropriate understanding of
the heat flux results. It was observed
that H from the LAS and H from the
EC correlated better when the wind
direction was from the east/southeast
direction (during the daytime). This
result suggests that the heat flux
source areas contributing to the LAS
and EC fluxes were similar for this
wind direction. During these periods
of better H correlation, the ET
derived from the LAS was generally
greater than or equal to the ET from
the EC.

Discussion
Comments on the LAS performance
are based on the assumption of

15

validity of the EC-measured H and
ET. Based on the results observed
in this study, it can be concluded
that, in general, the LAS-predicted
sensible heat fluxes correlated well
with EC-predicted H. However, the
correlation was impacted by apparent
LAS receiver and transmitter inherent
bias and misalignment issues. The
assumed inherent bias issues may
have actually been a result of setup
issues which were manifested in a
different power requirement for each
LAS, and would thus be a correctable
(and not inherent) bias. Further,
the conclusion of good LAS H
performance relies on the assumption
(above) that the disagreement
between LAS- and EC-derived H at
the AVRC site can be explained by
differences in the heat flux source
areas. Despite the fair agreement of H
fluxes between the LAS and EC, the
poor correlation between LAS- and
EC-derived ET is discouraging, which
was especially apparent for the dry
grassland site results. Nonetheless,
this result reflects on the accuracy/
spatial representativeness of the
Rn and G measurements and the

validity of the land surface energy
balance model rather than on
the ability of the LAS to predict
H. Therefore, it is tentatively
concluded that the LAS
can predict H
with reasonable
accuracy in both
dry and irrigated
environments,
but that caution
must be taken in
further predicting
ET as a residual
of the energy
balance. This
subsequently
limits the validity
Advisor José Chávez and Investigator Evan Rambikur.
of the LAS energy
Photo by Abhinaya Subedi
balance method for
estimation of crop ET for irrigation
research. We also are thankful to the
management or validation of other
Colorado State University Colorado
ET estimation methods.
Agricultural Experiment Station for
their support. In addition, we want
Acknowledgements
to extend our appreciation to the
following individuals, who in one way
The investigator and advisor would
or another participated in the study:
like to acknowledge and thank the
Allan Andales, Michael Bartolo, Lane
Colorado Water Institute (CWI) for
Simmons, Gale Allen, Darell Fontane,
sponsoring this study. We are grateful
and Stuart Joy.
to the CWI for supporting graduate
LAS 2 receiver at the AVRC site with data logger enclosure and laptop in the foreground. Alfalfa field
was being cut (harvested).

Photo by Evan Rambikur

16

Novel Technique for Evaluation of
Relationships Between Phytoplankton
and Dissolved Organic Material
Alia Khan, MS Candidate, Civil and Environmental Engineering, University of Colorado-Boulder
Faculty Advisor: Diane McKnight

M

aintaining adequate supplies
of clean drinking water is
vital to human health. Technological
advancements in water treatment
allow the removal and treatment
of some pollutants and pathogenic
bacteria. However, disinfectants such
as chlorine can react with natural
organic matter (NOM), which is
measured as dissolved organic
carbon (DOC) concentration, in
source waters to create disinfection
byproducts (DBPs), some of which
are known carcinogens. In recent
years, documented rises in DOC
concentrations have occurred across
the northeastern United States as a
response to the amelioration of acid
rain. In Colorado, changes in DOC
concentrations in the future may be
driven by increasing growth of algae,
a large source of DOC, due to a longer
period of ice-free
conditions
on lakes and
reservoirs under a
changing climate
and increasing
nutrient inputs
from atmospheric
deposition and
other anthropogenic sources.
These changes
may present
challenges to
ensure safe
drinking water
as a result of
increased DOC
in Colorado.
Removal of
the DBPs post

treatment is possible, but is often
difficult and costly for drinking
water utilities. Furthermore, because
the formation of chlorinated
disinfection by-products have been
directly correlated with DOC levels,
prevention of elevated DOC levels
pre-treatment could be more efficient
for drinking water utilities.
In the summer of 2010, the Colorado
Department of Public Health and
Environment (CDPHE) conducted
a High Quality Water Supply study
to assess the impact of algal growth
in Colorado lakes and reservoirs
on DOC concentrations and the
potential to form DBPs. Twenty-eight
lakes were sampled during July and
August, at the peak of summer stratification, and 10 other drinking water
reservoirs were sampled biweekly

from May through September 2010.
Chlorophyll-a, an indicator of algal
biomass, was used to assess the relationship between algal concentrations
and DOC concentrations. During
the field sampling, additional surface
samples were taken and preserved
with Lugol’s, an iodine based solution,
for phytoplankton identification and
enumeration with a Fluid Imaging
Technologies FlowCAM®. Funding
from the Colorado Water Research
Institute supported the development
of a protocol to analyze the phytoplankton samples.

Identification of phytoplankton
species and relative abundances can
help understand the drivers of the
phytoplankton dynamics and chlorophyll levels aiding in further comprehension for protecting source water
quality in lakes
and reservoirs.
Unlike traditional
microscopy,
the FlowCAM®
enables rapid
monitoring of
particles in fluid
by combining
flow cytometry
with microscopy.
Flow cytometry
is the process of
quantifying and
phenotypically
identifying cells
suspended in a
fluid by passing
them through
a laser beam
and capturing
the amount of
Adviser Diane McKnight and student Alia Khan, discuss how different phytoplankton species found in
the samples may impact the DOM quality of the respective lake sample. The species in this picture is
annabeana, a filamentous cyanobacteria found in high abundance in some of the samples.

Courtesy of Alia Khan

Colorado Water — May/June 2012

17

associated with each of the dominant
algal species. Total particles counts
were also noted.
Results show that Cyanobacteria,
diatoms, and green algae are the most
abundant algal groups present. In the
samples with the highest chlorophyll
a concentrations the phytoplankton
community was dominated by
filamentous cyanobacteria.

Geographic distribution of Colorado lakes and reservoirs sampled for the study.

light scattered by every particle. The
FlowCAM® automatically counts
and images each particle, while also
evaluating characteristics of the
digital image, such as shape and
intensity. Such imaging microscopes
are becoming used more frequently
by water treatment plants in order to
monitor algal activity in source water
lakes and reservoirs, such as in the
case of invasive species.
A newly developed protocol was
needed to take advantage of the
capability of this instrument’s
potential for new and novel applications to ongoing research on the
ecology of alpine and sub-alpine lakes
and reservoirs. A method has been
identified to routinely analyze the
samples from the High Quality Water
Study, which may be representative
of the range of phytoplankton

communities occurring in Colorado.
First, 150mL of the 500mL grab
sample was transferred to a settling
tube for 24 hours. Next, 130 mL of
the sample was aspirated from the top
of the sample in order to not disturb
the settled particles. The sample was
then transferred to a 50ml centrifuge
tube. If the sample looked visibly
cloudy, it was filtered with a 100um
mesh net to avoid clogging in the flow
cell. The 10X objective was used with
a 100um flowcell. Acetone was run
for five minutes to clean the flowcell
and tubing. The FlowCAM® was then
focused using a small volume of spare
sample. A 2mL of sub-sample was
then run through the FlowCAM®.
After the sample finished running,
image library files were made through
the interactive data platform, and
sorted based on image characteristics

The results from the analysis of the
phytoplankton using the FlowCAM®
are being analyzed to understand the
statistical relationships between the
phytoplankton species, chlorophyll-a,
nutrient levels, physical characteristics
of the lake, and DOC concentrations.
These results will be the basis of a MS
Thesis in the Environmental Studies
Department at University of Colorado
– Boulder.

Acknowledgements
Thanks to the Colorado Water
Institute for funding to support the
development of a protocol for the
Fluid Images FlowCAM for phytoplankton analysis of Colorado lakes
and reservoirs. We also appreciate
access to phytoplankton samples
collected for the High Quality Water
Study from the Colorado Department
Public Health and Environment to
assess algal impacts on disinfection
byproduct formation. Lastly thanks to
collaborators Prof. Fernando Rosario,
Prof. Scott Summers, and Amanda
Hohner at the Department of Civil,
Environmental and Architectural
Engineering at the University of
Colorado.

Cyanobacteria
(left) and
diatoms
were two
of the most
common
types of algae
found in the
study.

18

The Water Center of Colorado State University

Combined Source Infrastructure Assessment Model
Anne Maurer, MS Candidate, Civil and Environmental Engineering, Colorado State University
Faculty Advisor: Tom Sale

Figure 1. CSIAM Conceptual Model

Purpose of Study
The world is facing the critical
problems of increasing population,
climate change, and intensifying
competition for water resources.
With all of this, integrated utilization of surface and groundwater is
becoming an ever more important
strategy for sustaining water

production needed to address
irrigation, domestic supply, and
industrial demands. The term
“conjunctive use” is used to describe
the coordinated management
and development of surface and
groundwater. Conjunctive use
includes the ability to store and/or
utilize surplus water from one source

to meet the deficit of another source.
Unfortunately, design and analysis of
costs associated with conjunctive use
projects can be difficult. Challenges
include 1) appropriate sizing of water
storage, water treatment, and well
fields under conditions of evolving
demands; 2) resolving timing of
surface water use, groundwater
use, and groundwater storage; and
3) efficiently developing estimates
of costs associated with a range of
options.
The purpose of the study was
to develop a Combined Source
Infrastructure Assessment Model
(CSIAM) that can be used to 1)
resolve appropriate infrastructure and
operations for combined source water
systems and 2) develop feasibility
level cost estimates.
General approaches to conjunctive
use include combined use of surface
and groundwater with and without
groundwater recharge. The primary
advantages to systems with groundwater recharge include an ability

Anne Maurer with her faculty advisor, Tom Sale, Civil and Environmental Engineering, CSU.

Courtesy of Anne Maurer

Colorado Water — May/June 2012

19

to “bank” water in aquifers during
periods when surplus surface water is
available, and to reduce the necessary
capacities of surface water structures
(e.g., water treatment plants) to meet
peak demands.1 A central tenant of
the model is to recharge groundwater

when surplus surface water is
available. This is based on minimizing
the size of surface water reservoirs
and, correspondingly, minimizing
water losses to seepage and evaporation. Funding for the project was
provided by the Colorado Water

Institute and the Town of Castle Rock,
Colorado.

Research Objectives
The objective of this research is to
develop a model that can assist with
design and analysis of costs associated
with conjunctive use strategies. The
vision of the model is that of a general
tool that can be used for a wide
variety of water supply options. Figure
1 represents a conceptual view of
the combined source system that the
model is based on.
The research objectives for this study
included:

Figure 2. Comparison of Cumulative Pumping (+)/Injection (-) Volumes for Each Scenario

1. Development of both a
deterministic and stochastic
hydraulic model that determines
long-term water demands, surface
reservoir volumes, volume of
water delivered to a surface water
treatment plant, number of wells,
injection/recovery volumes
from wells, and resolution of
required infrastructure needed
for combined source system
operation
2. Development of a cost model
based on the hydraulic model
that estimates the capital costs,
operation and maintenance costs,
life-cycle costs, and present value
costs of the combined source
system being evaluated
3. Application of the model to
determine the least-cost option
that maximizes reliability of
the combined source system by
testing different surface water
treatment plant sizes.

Figure 3. Comparison of Life-Cycle Costs for Each Scenario

The town of Castle Rock was used as
a test case for the CSIAM.2 The town
is located in the high plains of central
Colorado at the base of the Front
Range. Historically, the Castle Rock
has relied primarily on groundwater
from the Denver Basin aquifers.

1. Pyne, R. D. G. (2005). Aquifer Storage Recovery: A Guide to Groundwater Recharge through Wells, ASR Press.
2. CH2M Hill, Inc. (2006). Town of Castle Rock Water Facilities Master Plan. Castle Rock.

20

The Water Center of Colorado State University

Three future water use scenarios are
considered, including:

supply plans are not included in this
analysis.

•

Results

Scenario A: Use of groundwater,
treated wastewater, and return
flows (treated surface water
collected downstream of the
town’s wastewater treatment
plant)

•

Scenario B: Use of groundwater
only

•

Scenario C: Use of a hypothetical
new surface water source

While the town of Castle Rock
provides a basis for applying the
model, the results should not be
viewed as having direct bearing on
future actions in the town of Castle
Rock. Many of the key issues that
will ultimately drive the town’s water

Each scenario was evaluated using
the deterministic and stochastic
version of CSIAM. Figure 2 presents
a comparison of the cumulative
groundwater use for a 30-year
period. Figure 3 presents life cycle
costs for a 30-year period. Figures
4 and 5, respectively, present the
number of pumping and injections
well needed. Results indicate that
combined use (Scenario A) results in
a 55 percent reduction in cumulative
groundwater pumping relative to a
groundwater-only system (Scenarios
B). Furthermore, Scenario A is $91
million less expensive than Scenario
B. Another key result is that Scenario

A is $231 million less expensive
than the surface water-only option
(Scenario C).

Conclusion
The CSIAM provides a basis for
resolving infrastructure components
and costs associated with combined
source water systems. Per the test
case, potential benefits of combined
source systems include reduced use of
groundwater and lower costs relative
to solely relying on groundwater.
Furthermore, the test case indicates
that the combined source system
has a lower cost than solely relying
on surface water. A comprehensive
presentation of the CSIAM, methods,
assumption and results is presented in
Maurer (2012).3

Figure 4. Number of Pumping Wells for Each Scenario

Figure 5. Number of ASR Wells for Each Scenario

3. Maurer, A. (2012). Combined Source Infrastructure Assessment Model. (Master’s Thesis) Colorado State University.

Colorado Water — May/June 2012

21

Figure 2. Irrigation practices
in the Arkansas River Valley.

Photo by Bill Cotton

Nutrient Management Practices
and Groundwater Protection
Assessing Adoption by Colorado Producers
Troy Bauder, Extension Water Quality Specialist, Colorado State University
Catherine M.H. Keske and Erik Wardle, Department of Soil and Crop Sciences,
Colorado State University

A

ccording to the U.S. Census
Bureau, the Earth’s estimated
human population has surpassed
seven billion. It is certain that each
and every one of these people will
require food and clean water for
survival. Nutrient use in agriculture is
closely tied to providing both of these
basic needs. Agricultural productivity
critically depends upon adequate
soil nutrients. Replenishment of soil
system nutrients removed by crop
production is not only necessary
for agricultural productivity, it is
also essential for the sustainability
of the soil resource. However, these
soil nutrients must be appropriately
managed in order to protect water
quality. This article summarizes
recent findings regarding Colorado
agriculture soil nutrient management

8

and the costs of adopting nutrient
management practices.

Nutrients in Cropping Systems
and the Environment
In the context of agricultural
production, the nutrients nitrogen
(N) and phosphorus (P) are typically
referred to as “macronutrients” due to
the large amounts necessary for crop
production relative to the other 16
essential nutrients for plants. While N
is ubiquitous in the environment as a
stable gas (N2), reactive Nitrogen (Nr)
forms of N such nitrate and ammonia
are most limiting for biological
systems. In most systems, Nr can be
a potential pollutant in both surface
and groundwater. Due to solubility
and use as a plant nutrient, the nitrate
ion (NO3-) form of nitrogen has been

a primary concern. While critical to
increased plant growth, water quality
impairments from N and P have been
well-documented and researched in
many environments and cropping
systems.

Colorado Policies and
Educational Programs
Groundwater contamination from
nitrate is currently a recognized issue
related to agricultural nutrients in
some areas of Colorado. Beginning
in the late 1980s, sampling began
to show certain regions of the state
where elevated nitrate-nitrogen
concentrations above the EPA
drinking water standard of 10 mg/L
(ppm) of nitrate-nitrogen could limit
the use of groundwater resources for
drinking water supplies. As concern

The WaTer CenTer of Colorado STaTe UniverSiTy

over these findings increased, in
1990 the Colorado General Assembly
passed proactive legislation for
addressing nitrate contamination
in groundwater. This legislation
was written as an amendment to
the Water Quality Control Act, and
established what would later become
the Agricultural Chemicals and
Groundwater Protection Program
(Groundwater Program). This
multi-agency program is led by the
Colorado Department of Agriculture
(CDA), who partners with Colorado
State University Extension and
the Colorado Department of
Public Health and Environment,
to achieve the following program
goals: 1) remedy areas of nonpoint
source groundwater impairment, 2)
prevent new contamination, and 3)
understand trends in groundwater
vulnerability and quality. The
Groundwater Program has used a
combination of three approaches
to achieve these goals: targeted
regulation, education through
demonstration and outreach, and
groundwater monitoring.

Costs of Adopting Nutrient
Management Practices and
Current Trends
In an effort to understand
current adoption of nutrient best
management practices (BMPs) by
Colorado agricultural producers,
the Groundwater Program conducts
periodic assessments of trends
and costs of nutrient management
practices. As follows is a summary of
methodology and results from a 2011
study.
The 2011 assessment consisted of a
mail-back survey that queried 2,000
irrigating agricultural producers
about BMP adoption rates and costs
for the 2010 growing season and
calendar year. The survey was pilot
tested with 16 producers, extension
specialists, agency personnel, and

Figure 1. Average annual expenditures on nutrient management practices

university faculty during development. Survey questions focused on
determining which BMPs producers
were using to determine their nutrient
rate, form, timing and placement. In
addition, practices that are generally
termed ‘precision agriculture’ were
queried to better understand how
producers are incorporating this
new technology into their nutrient
management. Producers were also
asked about nutrient management
practices that reduce off-field nutrient
transport, recordkeeping and cost of
BMP implementation.
The survey sample was drawn from
farm operators utilizing 100 acres or
more of irrigated land for production.
The National Agricultural Statistics
Service (NASS) stratified the sample
of Colorado irrigators by county.
Producer identities were anonymous
to researchers at all times, as surveys
were mailed directly to producers by
NASS. In order to ensure a successful
response rate, widely recognized
survey design methodologies were
followed. Surveys were initially
mailed in February 2011, and later in
March to those who did not respond

Colorado WaTer — JUly/aUGUST 2012

to the first mailing. Producers who
did not complete and return the
second mailing were contacted by the
NASS call center to increase response
rate.
The final overall response rate was
44.8 percent. To control for the
diversity of cropping practices in
Colorado, survey responses were
grouped into six geographic regions
based upon county. This regionalization also allows for comparison to
regional data presented in previous
Colorado surveys conducted in 1997
and 2002. A few highlights of the
survey are provided in the following
table and figure. A complete report
will be published in a CWI bulletin
soon.
Among the sampled producers,
certain BMPs, such as soil testing
in the E. Plains and S. Platte regions
showed very high adoption rates
(Table 1). Results indicate that
this basic BMP is well accepted by
irrigating producers in these areas to
help determine the correct amount
and type of nutrient required to
achieve high crop yields. In contrast,
plant tissue testing is adopted at a

9

Ark. Valley
41.1%

E. Plains
86.2%

Region of Colorado1
Mts.
S. Platte
21.2%
75.4%

San Luis Valley W. Slope
50.0%
44.7%

Soil Test
Analysis
72.5%
2.5%
43.1%
38.7%
21.8%
Split Apply N2 46.3%
Keep Written
32.1%
67.0%
26.3%
52.1%
49.1%
30.6%
Records
Establish Yield 30.4%
51.1%
14.1%
41.2%
30.6%
15.9%
Goals
Use Paid Crop 14.3%
47.9%
1.0%
22.8%
23.2%
1.9%
Consultants for
Advice
Deep Soil Test 12.5%
36.2%
0.0%
26.6%
18.6%
5.9%
Plant Tissue
5.4%
22.3%
4.0%
12.3%
20.4%
4.7%
Samples
1Respondents were asked to indicate multiple management practices incorporated therefore response estimates
calculated across region will not sum to 100.
2Refers to applying N fertilizer in two or more doses, typically one of these is during the growing season to maximize
efficiency
Table 1. Percentage of respondents incorporating selected nutrient management practices

lower rate across all regions since
the practice is typically limited to
certain higher value crops. Record
keeping, which is required to
qualify in some USDA cost sharing
programs, has been adopted at a
rate of less than 50 percent in four
of six regions. However, this is
still a higher rate than reported in
a previous survey. The percent of
producers using paid crop consultants to determine fertilizer rates
is highest in areas of higher value
crops and where crop consultants
are actively seeking clients.
Figure 1 shows expenses the
respondents reported for costs to
manage nutrients during the 2010
cropping season. These included
nutrient management BMPs and
other practices, such as conservation
tillage, that prevent nutrient losses
from fields. These costs varied
among regions similar to patterns
seen with BMP adoption, with the
exception being the Arkansas Valley
(figure 2). It is important to point
out that many of these costs also

10

have benefits, such as improved yield
or reduced fertilizer expenses, but
others do not have net return for the
producer. In many cases, cost-sharing
programs from the USDA Natural
Resources Conservation Service and
other programs can help producers
with these expenses and improve
adoption.
A key result from this survey is that
nutrient BMP adoption and expenditures on BMPs varies widely by
region of the state. These differences
are expected, as Colorado’s irrigated
farming regions are diverse in terms
of crop and livestock systems utilized,
irrigation systems and water sources,
nutrient type and amount applied,
input costs, and management styles.
Additionally, crop landscapes vary
from high altitude mountain hay
meadows to intensive vegetable row
crops in some river valleys. In general,
nutrient BMP adoption is highest
within the regions where fertilizer and
manure nutrients are utilized more
and in areas with higher value crops.

Summary
Supplemental nutrients, particularly
N and P, are critical components of
highly productive, profitable irrigated
agriculture and to meet the food
intake requirements of an increasing
global population. This study found
that most of the Colorado producers
who responded to our survey are
implementing some level of nutrient
management practices to enhance
nutrient use efficiency and prevent
losses from irrigated fields. The
BMPs with higher rates of adoption
tend to be those with lower costs
or are cost neutral to the producer,
whiles others may require incentive
programs to achieve higher levels of
adoption. Ultimately, the decision on
whether to implement a BMP or suite
of BMPs can only be made at the
local watershed scale, incorporating
local knowledge of field conditions
and cropping systems.
Contact Troy Bauder, Extension
Specialist 970-491-4923.
[email protected]

The WaTer CenTer of Colorado STaTe UniverSiTy

A wetland and pond adjacent to an irrigated
pasture in the Livermore valley. Both the wetland
and pond are entirely dependent on irrigation
canal leakage for hydrologic maintenance.

Incidental Wetland Creation in
an Irrigated Landscape
Jeremy Sueltenfuss, MS Candidate, Ecology, Colorado State University
Faculty Advisors: Rick Knight, Reagan Waskom, and David Cooper

Introduction

A

gricultural productivity in the
semi-arid American West has
relied on irrigation for centuries.
Early irrigation efforts were often
located in floodplains adjacent to
rivers and utilized small, hand dug
canals to irrigate pastures (Morgan
1993). As larger areas of land were
settled, canals became larger and
longer, and transported water to
uplands far from the original water
source. Irrigated land in the West
has continued to expand from
three million hectares (ha) in 1900
(Pisani 2002) to over 17 million ha of
irrigated land today (Gollehon and
Quinby 2000).
Irrigation canals across the American
West are known to have water
losses up to 50 percent due to
leakage (Luckey and Cannia 2006).
Though the negative impacts of
water diversions on rivers are well

documented (Strange et al. 1999),
the environmental changes created
by irrigation canal leakage remain
understudied. Although some authors
have suggested a direct competition
for water between irrigated agriculture and wetland ecosystems (Lemly
et al. 2000), others have mentioned
the possibility of canal leakage
creating and maintaining wetland and
riparian habitat (Kendy 2006).
Wetlands are an important part of a
landscape, yet estimates of historical
wetland loss due to river diversions
and land conversion in some western
states range between 50 and 90
percent (Yuhas 1996). Because
wetlands provide habitat to a disproportionate number of animal species
and perform essential ecosystem
services related to water quantity and
quality (Zedler 2003), understanding
the influence of irrigation canals on
the hydrologic regime of wetlands is
necessary for future water planning

Colorado WaTer — JUly/aUGUST 2012

and wetland conservation. The
present study sought to answer the
following questions: (i) Are there
hydrologic processes linking canals
and reservoirs to wetlands, and (ii)
What types of wetlands are supported
by irrigation canals?

Study Area
North Poudre Irrigation Company
(NPIC) is one of many irrigation
water delivery companies in northern
Colorado. Located in the South Platte
River Basin on the plains and foothills
north of Fort Collins, Colorado, NPIC
has a total service area of 23,300 ha
and delivers water to 9,700 ha of
irrigated land utilizing 16 holding
reservoirs and approximately 250 km
of canals (Figure 1), 89 percent of
which are unlined earthen canals that
have been in place for over a century.
Water diverted from the North
Fork and main stem of the Cache la
Poudre River is transported through

11

the canal system from April through
September to upland areas away
from river corridors. In 2010, NPIC
diverted approximately 89,400 acre
feet, 45 percent of which was lost to
evaporation and canal seepage (pers.
comm. NPIC manager). Previously
measured NPIC canal water losses
range from zero percent to 50 percent
per canal (Riverside Technology, Inc.
2005).

Methods
Wetland Mapping
Wetlands were mapped using
National Wetland Inventory maps
from 1975 and were refined using
aerial images in ArcMap 10. The
hydrologic source of each mapped
wetland was visually determined
with aerial photographs by tracing
surface water flow paths or subsurface
flow paths as detected by increased
primary productivity back to a source.
Vegetation was characterized using
aerial images for every wetland
in the study area. Because aerial
images were not precise enough to
identify vegetation to the species
level, vegetation was separated into
three broader categories: “Marsh”
communities visible in the image as
tall, dense stands of Typha latifolia,
“Meadow” communities visible as
shorter stands of sedges such as Carex

Figure 1. Study area map of North Poudre Irrigation Company canals and reservoirs adjacent to the
Cache la Poudre River in northern Colorado.

spp, and “Salt flats” visible due to the
presence of white salt on the land
surface with sparse vegetation such as
Atriplex spp.

Wetland Hydrology
A total of 70 monitoring wells were
installed in 20 wetlands throughout
the NPIC service area. Wells were
dug to approximately one meter

depth, cased with 1.5 inches schedule
40 PVC pipe with holes drilled
approximately every five centimeters
and backfilled with native soil. Water
tables were measured approximately
every two weeks from May through
November 2011. Pressure transducers
(In-Situ Rugged Troll 100) were
installed in six monitoring wells to
record hourly water table depths.
Wetland water table fluctuations were
compared to both daily canal flow
and precipitation. Daily canal flow
was estimated from daily irrigation
order records from NPIC customers
along each canal. Precipitation data
were collected from six precipitation
stations in the Community
Collaborative Rain, Hail & Snow
Network (www.cocorahs.org).

Results
Wetland Mapping
Aerial image of an irrigation canal transporting water across a semi-arid landscape. Various points
of water leakage in the canal lead to the flow of water down the landscape, converging to create
wetland habitat in topographic depressions.

12

A total of 176 wetlands covering 652.3
ha were mapped within the NPIC

The WaTer CenTer of Colorado STaTe UniverSiTy

boundary. Of these, 56 wetlands
covering 173.7 ha were associated
with irrigation canal leakage (Table
1). According to previously measured
canal water loss data, 50.6 percent
of canals had high percent water
loss greater than 17 percent, 36.5
percent of canals had moderate water
loss between seven percent and 17
percent, and 12.8 percent owf canals
had low water loss less than seven
percent. The majority of wetlands
associated with canals were below
high water loss canals with percent
water losses greater than 17 percent.
Along with canal seepage, seepage
from pond and reservoir dams was a
major hydrologic source for wetlands,
sustaining 52 wetlands totaling 186.7
ha. Within the study area, agricultural
water storage, conveyance losses, and
application were visually attributable
for 89 percent of the number of
wetlands, and 92 percent of the total
wetland area.
Within the study area, 43 percent (279
ha) of the wetland vegetation was
marsh, 40 percent (263 ha) meadow,
and 17 percent (111 ha) salt flats.

Wetland Hydrology
Wetland water table depths adjacent
to canals with high water loss were
heavily influenced by changes in canal
flow (Table 2). The highest wetland
water table depth change recorded
Table 1. Census of mapped wetland attributes
corresponding to their hydrologic source.
Canals are separated by percent water loss as
previously measured from Riverside, Inc. The
number of wetlands, the total wetland area,
and average wetland size are reported for each
infrastructure category. “Intentional Water
Delivery” refers to managed wetlands with
water deliveries. The hydrologic source for 18
wetlands located below multiple irrigation canals
could not be determined, and are reported
as “unknown source, below canal.” Only two
wetlands were located above irrigation canals.
“Tail water” refers to wetlands located at the
low point of irrigated fields. “Pond/reservoir
outlet” refers to wetlands downhill of ponds or
reservoirs. “Reservoir Fringe” refers to wetlands
along the banks of NPIC reservoirs.

from when a canal was flowing to
when it stopped flowing was 131.4
cm. The Buckeye Main canal recorded
the highest flows through the
irrigation season, and its interaction
with an adjacent wetland serves as an
example consistent with most instrumented wetlands. Groundwater levels
in this wetland immediately adjacent
to the Buckeye Main canal increased
as canal flow increased throughout
the summer. Once the canal stopped
transporting water in the fall, the
water table in the wetland declined
by 60 cm (Figure 2), with very little
response to precipitation throughout
the year. The trend of decreasing
wetland water tables following the
drying of irrigation canals was seen
in the majority of instrumented
wetlands.

Discussion
The functions of agricultural ditches
running through areas already
saturated and those traveling across
arid land are fundamentally different.
For already saturated land, ditches
are used to lower water tables and
manipulate them for the benefit of
crops, often leading to a decline in
wetland area (Krause et al. 2007). In
arid and semi-arid regions, ditches
are used to convey water from river
corridors, groundwater pumping
stations, and reservoirs to uplands

where it is applied to arid lands.
Although intended to irrigate arid
lands to produce livestock forage
and crops, not all diverted water
is consumptively used by plants
(Fernald et al. 2010). As seen in
this study, excess water that leaks
from canals and dams, as well as the
over-application of water to fields,
creates a large amount of wetlands on
previously arid land.
The transport of water from streams
and reservoirs in irrigation canals
and ditches, some with seepage
rates exceeding 50 percent, and the
excessive amount of water applied to
some irrigated fields has resulted in
the unintentional creation of a wide
range of wetland types in this study
area, and likely in many parts of the
western U.S. as well. Though some
authors suggest that competition
for water occurs between wetlands
and agriculture (Lemly et al. 2000),
irrigated agriculture appears to
have played an important role in
the redistribution of water and the
creation and maintenance of a large
proportion of the total wetland area
in many western landscapes (Peck et
al. 2001).
Non-riparian wetlands have
groundwater as a primary water
source (Mitsch and Gosselink 2000)
and are generally independent of
precipitation in arid regions (Laubhan

Wetland hydrologic source

# Wetlands

Total
Wetland
Area (ha)

<7% Loss Canal

3

7.1

2.4

7-17% Loss Canal

17

31.8

1.9

>17% Loss Canal

36

134.8

3.7

Intentional Water Delivery

12

98.5

8.2

Unknown Source, Below Canal

18

51.1

2.8

Above Canal

2

1.1

0.5

Tail Water

7

13.1

1.9

Pond/Reservoir Outlet

52

186.7

3.6

Reservoir Fringe

29

128.1

4.5

Colorado WaTer — JUly/aUGUST 2012

Average
Wetland Size
(ha)

13

2004). Kendy et al. (2004) found that
changes in groundwater had large
impacts on wetland ecosystems.
Canals may therefore act analogously
to streams in arid regions, and
influence or control water table
position through the subsurface
movement of water from the canal
to surrounding areas (Francis et al.
2010). Because canal seepage can
raise local water tables (Harvey and
Sibray 2001), the current wetland
distribution in many agricultural
areas is likely a result of the location
and functioning of the irrigation
infrastructure (Kendy 2006).
Hydrologic regime is often identified
as the key determinant of wetland
structure and function (Mitsch and
Gosselink 2000). This study has
highlighted the importance of canal
seepage in influencing the hydrologic
regime of wetlands and its control
over the types of wetlands in an
agricultural landscape. Similar to
previous accounts (Crifasi 2005)
many wetlands in this study were
found on hill slopes directly below
irrigation canals and were dominated
by wet meadow plant species,
including members of the genera
Juncus and Carex. Slope wetlands
are often the first wetland type to be
lost due to land use change (Skalbeck
et al. 2008), but are thought to
support high biodiversity (Stein et al.
2004), and may be some of the more
resistant wetlands to future climate
change (Winter 2000). Wetlands that
have been created by irrigation water
may be indistinguishable in form and
floristic composition from wetlands
with more natural water sources (Peck
and Lovvorn 2001) and may provide
greater ecosystem services due to
their longer hydroperiods (Kendy
2006), such as biodiversity support
(Rumble et al. 2004), flood abatement
(Zedler 2003), and water quality
improvements (Fennessy and Craft
2011). Lining canals, transferring
irrigation water to cities, or altering

14

current irrigation practices in the
name of increased efficiency could
therefore have detrimental impacts
on both wetland functions (Fernald
and Guldan 2006) and biodiversity
(DiNatale et al. 2008).

Conclusions
Water in the American West is
a limited resource, and its use is
contentious between agriculture,
growing municipalities, and the

environment. Though agricultural
practices are often viewed as
inefficient, large wetland complexes
are maintained through seepage from
canals, pond and reservoir dams, and
tailwater from irrigated fields, as well
as through interactions with shallow
aquifers. Because water quality and
biodiversity support are growing
concerns in many landscapes, future
work should focus on the functions
and services of agricultural wetlands,
as well comparisons between the

Figure 2. The effect of daily precipitation and adjacent canal flow on water tables from one wetland.
Monitoring wells were located in two vegetation communities in a wetland adjacent to the Buckeye
Main canal during the summer of 2011. The dominant plant species occurring at each well is used as
that well’s name. Water levels represent hourly data within a Carex nebrascensis community (solid
line) and bi-weekly data within an Eleocharis macrostachya community (dashed line). Points along the
dashed line represent specific measurements. A 50 day lag occurred between the declining flow in the
canal and the declining groundwater level for the C. nebrascensis community, with a shorter lag for the
E. macrostachya community.

The WaTer CenTer of Colorado STaTe UniverSiTy

Infrastructure Category Category Amount
< 7% Loss Canal
7-17% Loss Canal

> 17% Loss Canal

Pond/Reservoir

32.2 km
13% of total
91.5 km
36% of total
127 km
51% of total

1571.2 ha
Surface area

Intrumented Wetlands
Distance to
Source (m)
13.5
135
30.2
9.8
41.7
16.6
13.2
10.3
6.8
10.7
11.7
50
58.8
23.9
70
15.7
16.4
20.8
49.4

Colorado WaTer — JUly/aUGUST 2012

Water Table
Change (cm)
83
50.6
None
None
None
103.6
14.6
12.4
17.7
51.3
None
131.4
59.3
102.7
120.5
52.7
None
None
None

location of historic wetlands and
those currently in existence. Water
transfers and changing agricultural
practices to increase water efficiency
put existing wetlands at risk,
necessitating an understanding of
policy and management implications
on agricultural wetland ecosystems.
Current wetlands may only be as
permanent as the irrigation practices
that sustain them.

References avaliable upon request.
Table 2.Characteristics of NPIC canals and
reservoirs as well as the instrumented wetlands
associated with them. The length of each canal
and the percent of total canals are reported for
each canal percent loss category as well as
the total surface area of ponds and reservoirs.
Characteristics of the instrumented wetlands
associated with each category include the
distance to the associated category as well as
the wetland water table response to the stopping
of the adjacent canal flow. Note that most
wetlands had changes in water table position in
response to changes in canal flow.

15

Report on Arkansas River Valley Irrigation Available

T

he Colorado Water Institute
(CWI) Completion Report
221, Irrigation Practices, Water
Consumption, & Return Flows
in Colorado’s Lower Arkansas
River Valley: Field and Model
Investigations, has been released
and made available (see below for
more information). The report is
based on field investigations taking
place over the 2004-2008 growing
seasons in the Lower Arkansas River
Valley of Colorado. The study’s
main purpose was to describe and
compare surface irrigation and
sprinkler irrigation practices and
their interaction with the larger
stream-aquifer system of the Lower
Arkansas River Valley. Primary
funding came via grants from the
Colorado Water Conservation Board,
the Colorado Division of Water
Resources, the Colorado Department
of Public Health and Environment,
the Southeastern Colorado Water
Conservancy District, the Lower
Arkansas Valley Water Conservancy
District, and the Colorado
Agricultural Experiment Station.

Summary
By Timothy K. Gates, Luis A.
Garcia, Ryan A. Hemphill,
Eric D. Morway, and Aymn
Elhaddad
The LARV in Colorado has a
long history of rich agricultural
production, but is facing the
challenges of soil salinity and
waterlogging from saline shallow
groundwater tables, high concentrations of salts and minerals in the river
and its tributaries, water lost to nonbeneficial consumption, and competition from municipal water demands.
Significant improvements to the
irrigated stream-aquifer system are
possible, but they are constrained by

28

the need to comply with the Arkansas
River Compact. Making the best
decisions about system improvements
and ensuring compact compliance
require thorough baseline data on
irrigation practices in the LARV. This
report summarizes the methods,
analysis, results, and implications of
an extensive irrigation monitoring
study conducted by Colorado
State University (CSU) during the
2004-2008 irrigation seasons in
representative study regions upstream
and downstream of John Martin
Reservoir (referenced herein as
Upstream and Downstream). A total
of 61 fields (33 surface-irrigated, 28
sprinkler irrigated) were investigated.
Results from 523 monitored irrigation
events on these fields are presented.
Data and modeling results from
more extensive studies conducted by
CSU between 1999 and 2008 also are
provided.
Data on applied irrigation, field
surface water runoff, precipitation,
crop evapotranspiration (ET),
irrigation water salinity, soil water
salinity, depth and salinity of groundwater tables, upflux from shallow
groundwater, crop yield, return flows
to streams, and salt loads to streams
are presented. Deep percolation and
application efficiency for irrigation
events on each field are estimated
using a water balance method implemented within the CSU Integrated
Decision Support Consumptive Use
(IDSCU) Model. Tailwater runoff
(surface water runoff at the end of a
field) fraction ranges from zero to 69
percent on surface irrigated fields,
averaging about eight percent, while
deep percolation fraction ranges from
zero to 90 percent, averaging about 24
percent. Application efficiency ranges
from two to 100 percent on surface
irrigated fields, with an average of
about 68 percent. No significant

runoff is observed on sprinklerirrigated fields, and estimated deep
percolation typically is negligible.
On sprinkler-irrigated fields average
application efficiency is about 82
percent, but in many cases these
fields are under-irrigated. Upflux
from shallow groundwater tables
below irrigated fields is estimated
to average about six percent of crop
ET, ranging between zero percent
and 40 percent. Average measured
total dissolved solids concentration
of applied surface irrigation water is
532 mg/L Upstream and 1,154 mg/L
Downstream. Average estimated salt
load applied per surface irrigation
event is 997 lb/acre Upstream and
2,480 lb/acre Downstream. Average
estimated salt load applied per
sprinkler irrigation event is 1,217
lb/acre Upstream and 446 lb/acre
Downstream. Soil saturated paste
electrical conductivity averaged
over all Upstream fields ranges from
3.7-4.7 deciSeimens per meter (dS/m)
over the monitored seasons and from
4.5-6.4 dS/m over Downstream fields.
Water table depth averaged over
Upstream fields varies from 7.8-12.1
feet over the monitored seasons and
average specific conductance (EC)
of groundwater varies from 1.8-2.3
dS/m. Water table depth averaged
over Downstream fields varies from
12.6-15.0 feet with average EC from
2.3-3.0 dS/m. Analysis reveals trends
of decreasing crop ET with increasing
soil salinity on several investigated
fields. Trends of decreasing relative
crop yield with increasing soil salinity
on corn and alfalfa fields also are
detected.
Calibrated regional groundwater
models indicate an average recharge
rate to shallow groundwater
of 0.10 in/day and 0.06 in/day
over modeled irrigation seasons
1999-2007 Upstream and 2002-2007

The WaTer CenTer of Colorado STaTe UniverSiTy

Irrigation Practices, Water Consumption,
& Return Flows in Colorado’s Lower
Arkansas River Valley
Field and Model Investigations
By Timothy K. Gates, Luis A. Garcia, Ryan A. Hemphill, Eric D. Morway, and Aymn Elhaddad

Completion Report No. 221

Downstream, respectively. Upflux to
non-beneficial ET in the regions is
estimated to be about 26,000 ac-ft/
year Upstream and 35,000 ac-ft/year
Downstream, with an approximation
for the entire LARV being 82,000
ac-ft/year. Average groundwater
return flow rate to the Arkansas
River within the Upstream and
Downstream regions is estimated

CAES Report No. TR12-10

as 30.9 ac-ft/day per mile and 12
ac-ft/day per mile along the river,
respectively. Salt load in return flow
to the river over the modeled years is
estimated at about 93 tons/week per
mile Upstream and about 62 tons/
week per mile Downstream.
The significance and implications of
these findings are discussed. Also,
a number of specific questions of

Colorado WaTer — JUly/aUGUST 2012

concern to water managers and
regulatory agencies are addressed.
The full report will can be accessed at
www.cwi.colostate.edu, or obtain a
hard copy by contacting the Colorado
Water Institute, E102 Engineering,
1033 Campus Delivery, Fort Collins,
CO 80523-1033, 970-491-6308, or
[email protected].

29

Guiding Landowners and Agencies Dealing
with Domestic Energy Development in
the Northern Plains and Mountains
Julie Kallenberger, Assistant Regional Water Coordinator, Colorado Water Institute
Troy Bauder, Water Quality Specialist, Department of Soil and Crop Sciences, Colorado State University
Reagan Waskom, Director, Colorado Water Institute
Jim Bauder, Professor Emeritus/Adjunct, Montana State University
Ginger Paige, Professor, University of Wyoming

A

s recently as a decade ago, the
impacts of oil and natural gas
development on water resources were
mainly confined to issues related to
off-shore drilling for oil, ruptured
pipelines, and grounded oil tankers.
Today, new terms, like coalbed
methane (CBM), coal seam natural
gas, and drilling and extraction
practices, like horizontal drilling and
fracking (formally known as hydraulic
fracturing), are gaining a lot of
attention, particularly in the Northern
Plains and Mountains (NPM) Region.
Much of this attention is due to better
understanding of the potential for
oil and gas resource development

to affect land and water resources
by industry, society, and regulatory
agencies.
Regarding the current thrust of
unconventional oil and gas development in the NPM Region, landowners
frequently voice concerns about
whether fracking can or will contaminate their domestic water supplies.
Irrigators wonder whether discharge
of CBM-produced water will cause
changes in irrigation water quality
and regulatory, and governmental
agencies need to know what values
should be assigned to water quality
parameters to assure protection of
water resources.

The NPM Regional Water Program,
a USDA sponsored partnership of
six land-grant universities, initiated
a project to help guide landowners
and agencies dealing with the impacts
of domestic energy development
on their land and water supply. The
activities performed in this project
have led to the development of a
widely-viewed informational video
documentary, online educational
tools, stakeholder forums, conferences, regional workshops, and
productive collaborative partnerships
among landowners, governmental
agencies, and oil and gas companies.

Sodicity and salinity impacts to corn crop irrigated with river water
downstream of CBM discharge area.

Photo by Troy Bauder, Colorado State University

22

The Water Center of Colorado State University

Advances in Oil and Gas
Extraction Technologies and
Impacts on Regional Water
Supplies
In the mid-1990s, the natural
gas industry developed efficient
processes for locating and extracting
CBM from shallow coal deposits
throughout the Intermountain West.
A significant increase in natural gas
prices prompted the drilling and
development of nearly 31,000 CBM
wells in the NPM Region by 2010.
Concurrently, the increase in crude
oil prices prompted expanded exploration and drilling for oil and natural
gas reserves. This expanded drilling
was complemented by new drilling
techniques and improved methods for
withdrawing natural gas and crude oil
from underground oil reserves.
The two most noteworthy advances
have been horizontal drilling and
improved hydraulic fracturing, a
process whereby industry-proprietary
chemicals, mixed with large volumes
of water and sand, are injected into
underground geologic formations to
open and expand pores and channels
so that oil and gas can more readily
flow to the well cavity. Additionally
driving the oil and gas development
industry has been the discovery of
large, prolific oil and gas reserves
contained in the Niobrara and Bakken
shale deposits, underlying southeast
Wyoming, northeast Colorado,
northeast Montana, and northwest
North Dakota. Extraction of CBM
requires pumping and disposing of
often large volumes of water from
coalbeds. This water ranges in quality
from nearly fresh to brackish and
saline. Pumping and discharge of
water from CBM operations onto the
landscape and into storage impoundments and rivers has increased
dramatically in the past decade.
The discharge and disposal of CBM
produced water was found to alter the

quality of some
Sampling CBM discharge water in the Raton Basin of Colorado.
Photo by Troy Bauder, Colorado State University
streams, rivers,
and groundwater.
Research has
documented that
CBM production
water can often
negatively alter
soil properties as
well. Each of these
circumstances can
pose a threat to the
quality of water
used for irrigation,
livestock watering,
range land,
The team and their partners
and aquatic habitat sustainability.
developed a Land & Water Inventory
Additionally, severance of mineral
Guide for Landowners in Areas
rights from surface rights often means
of CBM Development which has
that landowners, whether dealing
been used to educate landowners
with CBM or unconventional oil/
concerning CBM issues and assist
gas drilling, have little control over
with monitoring and assessment
drilling operations and must rely on
of impacts to land and water
surface use agreements and negoresources. Team members also
tiations with gas and oil production
produced Prairies and Pipelines, a
companies to guide operations on the
public television documentary that
landscape.
addresses the science and social
issues behind CBM recovery and
Educational Resources
associated water management. Also,
The NPM Regional Water Team
inquiries from private well owners,
responded to needs of landowners,
Extension field staff, and EPA Region
concerned citizens, and governmental
8 staff prompted the development
agencies and administrations by:
of a comprehensive website on the
• Researching impacts of CBM
hydraulic fracturing extraction
produced water discharges
processes and potential implications
on irrigation water quality
for water resources. This website
and management alternatives
provides information about drilling
on semi-arid landscapes and
and hydraulic fracturing techniques,
irrigation water
water quality testing, surface use
agreements, perspectives on water
• Developing educational resources
quality and quantity, and potential
for landowners, regulatory and
health issues related to hydraulic
natural resource management
fracturing.
agency personnel, litigants,
attorneys, consultants, scientists,
For additional information about the
students, the media, educators,
NPM Regional Water Program and
and policy makers
these resources please visit
www.region8water.org and
• Transferring science-based
http://waterquality.montana.edu/
information to the general public,
docs/methane.shtml.
media, landowners potentially
impacted by CBM extraction, and
other decision makers

Colorado Water — September/October 2012

23

Paleohydrology of the Lower Colorado River Basin
and Implications for Water Supply Availability
Jeff Lukas, Western Water Assessment, University of Colorado
Lisa Wade1, Department of Civil and Environmental Engineering, University of Colorado
Balaji Rajagopalan, Department of Civil and Environmental Engineering, University of Colorado

Introduction
As the annual demand on the
Colorado River system approaches
the annual supply, the contribution
from the Lower Colorado River Basin
(LCRB)—on average about 15 percent
of total system flows—becomes more
critical. In fall 2010, our research
team began a project to develop
new paleo-reconstructions of LCRB
hydrologic variability from tree-ring
records, and incorporate them into
an assessment of water supply risk
for the Colorado River Basin. This
project was primarily motivated by
the interests of the Colorado River
District, which is responsible for
the conservation, use, protection,
and development of Colorado’s
apportionment of the Colorado
River. The project was carried out
with funding from the Colorado
Water Institute, the Colorado
River District, the Western Water
Assessment, and graduate student
support from the Department of Civil
and Environmental Engineering,
University of Colorado.
The general framework of the project
was to (1) develop naturalized flow
records for the Gila and non-Gila
subbasins of the LCRB (Figure 1);
(2) compile existing tree-ring data
for the LCRB (described in the April
2011 article); (3) generate tree-ring
reconstructions of streamflow using
multiple methods; and (4) use the
reconstructions to inform improved
system risk modeling of the entire
Colorado River Basin. A previous
article for Colorado Water (April
2011) described in some detail the
context, objectives, and methods of

Figure 1. The Lower Colorado River Basin
(LCRB). The Gila River basin is outlined in
black, and the non-Gila portion of the LCRB is
outlined in red. The Gila River near Dome, AZ
gage is shown in purple. Reclamation’s nine
CRSS model nodes within the LCRB are shown
in blue and yellow (see text for explanation).

the project, so we will not repeat that
information here.

Results
The results for the main components
of the project are described below.
Analyses of gaged flows in the LCRB
and development or selection of
naturalized annual flow records for the
historic period (~1906 to present) to
use as targets for the paleohydrologic
reconstructions for these two locations:
•

The flow for the Gila River near its
confluence with the Colorado

•

The intervening flow on the
Colorado River between Lee Ferry
and Imperial Dam

The hydrology of the Gila River is
almost entirely modified by reservoir
operations and depletions before
it joins the Colorado River, and
these modifications began in the

first decade of the 1900s (Figure
2). Several headwater gages on the
mainstem Gila and its major tributaries (Salt River, Verde River, Tonto
Creek) are above the dams, and most
diversions and remain mainly natural
(Figure 2). In 1946, the Bureau of
Reclamation developed estimates of
natural flow at gages downstream of
the dams and diversions, including
Dome, Arizona (the closest gage to
the mouth), for the period 1897–1943.
After extensive analysis of the gaged
records for the Gila River Basin,
we developed a local polynomial
regression model between the Bureau
of Reclamation-estimated naturalized
flow at Dome for the 1897–1943
period and the near-natural gaged
flows at the headwater gages. The
modeled estimated natural flows for
the Gila near Dome cover the period
1915–2010. We also retained the
gaged flows at Dome as a calibration
series since they represent the inputs
to the Colorado from the Gila under
current managed conditions and are
more relevant for the system risk
modeling as we implemented it.
The naturalized intervening flow
on the Colorado River between Lee
Ferry and Imperial Dam proved to
be an elusive quantity. Reclamation
maintains a natural flow dataset of the
Colorado River and major tributaries
(see Figure 1) for the 29 input nodes
for their Colorado River Simulation
System (CRSS) model, but for the
nine nodes in the LCRB, these flows
have not been explicitly naturalized,
and some may contain artifacts of
the water-balance modeling used to
reconcile the total flows entering the

1 Current affiliation: Riverside Technology, Inc., Fort Collins

2

The WaTer CenTer of Colorado STaTe UniverSiTy

top of the LCRB with those gaged at
the bottom (Imperial Dam). In fact,
we discovered that of the nine LCRB
nodes, flows from 1906–2008 at five
of the nodes (shown in blue in Figure
1) were well-correlated with observed
precipitation and streamflow in
adjacent basins, while the flows at the
other four nodes (shown in yellow)
were essentially uncorrelated with
observed hydroclimate. We found
also that the total flows at the five
“good” nodes were well-correlated
with flows simulated by Reclamation
using the VIC hydrology model. Thus,
we retained only the flows at the five
good nodes to represent the Lee Ferry
to Imperial reach, for calibration
with the tree-ring data, recognizing
that the magnitudes of the total flow
at all nine nodes will require further
investigation. Reclamation engineers
have indicated to us that as a followup
to the Colorado River Basin Study,
they will revisit their natural flows
data for the LCRB.
Generation and evaluation of tree-ring
reconstructions for Gila flows and
the mainstem intervening flows using
multiple methods
Tree-ring paleohydrologic reconstructions have been generated using many
different statistical approaches, all
of which have particular strengths
and weaknesses. The most common
approach has been multiple linear
regression (MLR); thus, to establish
a baseline for comparison with new
approaches, we used two variants
of forward-stepwise MLR, with
and without Principal Components
Analysis (PCA). We also used Lowess
regression, which uses a smoothedand-fitted-curve relationship instead
of a linear relationship, and a
recently-developed non-parametric
K-nearest-neighbors (K-NN) method.
We also implemented two new
statistical methods for tree-ring
reconstruction of streamflow. For the
first method, Local Poly, we employed

a cluster analysis on our regional
network of tree-ring chronologies to
identify spatially coherent subregions
that have a common climate signal,
then performed PCA on the clusters
to obtain the main modes of variability. The main modes are used
as predictors in a local polynomial
model, within a Generalized Linear
Model (GLM) framework, fit to the
observed natural streamflows. This
approach is similar to the K-NN
resampling method but has the
ability to produce flows beyond the
range of the observed data while also
capturing non-linearities. The second
method introduces the extreme
value analysis (EVA) peaks-overthreshold (POT) method to tree-ring
reconstructions of streamflow. The
EVA-POT models the probability
of threshold exceedance, and the
magnitude of exceedances, and is
especially suited for reconstructing
intermittent streamflow, such the
gaged flows at the
mouth of the Gila
River.
The tree-ring
reconstructions of
Gila River natural
flows using five
different methods
explain between
41 percent and
61 percent of
the variance,
respectively, in
the observed
flows. They all
capture the low
flows better than
the high flows,
as is typical
for tree-ring
reconstructions,
and they track
each other very
well both during
the observed
period (Figure
2) and the longer

Colorado WaTer — noveMBer/deCeMBer 2012

paleo-period (Figure 3), testifying
that the underlying tree-ring information is robust to the statistical method
used. The Local Poly and Lowess
methods are able to express larger
magnitudes in high-flow years than
the MLR reconstructions. Across the
methods, mean reconstructed flows
are generally lower before 1900 than
after 1900, and the 20th century also
appears to be anomalous compared
to preceding three centuries in having
two multidecadal wet periods. We
used three methods to reconstruct the
mainstem Colorado River intervening
flow, with lower explained variance
(37 percent–52 percent) than with
the Gila, probably reflecting the
aforementioned issues with the
observed natural flow record used to
calibrate the reconstructions. As with
the Gila, the mainstem low flows are
reconstructed more accurately than
the high flows.

Figure 2. Five different methods for tree-ring reconstruction of natural
annual streamflows (1915–2005; colored lines) for the Gila River
near Dome, AZ, compared with the estimated natural streamflows
(“Observed”). The “Local Poly” model (blue line) also has gray shading
showing the five and 95 percent confidence intervals around that
reconstruction.

Figure 3. Same as Figure 2, but showing the full common length (1612–
2005) of the five tree-ring reconstructions of natural flows for the Gila
River near Dome, AZ. Note that the reconstructions show several annual
flows higher than any observed flow, and that the 1900s were unusual in
having two sustained wet periods.

3

study, the waterbalance model
was driven by
natural variability alone and
with two climate
change scenarios
(progressive
flow reductions),
under two
Figure 4. Tree-ring reconstruction of the “as-managed” gaged annual
flows for the Gila River near Dome, AZ (1612–2005) using the Extreme
different
Value Analysis (EVA) Peaks-over-Thresholds (POT) method. Most of the
reservoir
reconstructed flows are zero, reflecting the high intermittency of the
gaged annual flows. The occasional high discharges into the Colorado
operation rules
River allow some reduction in the releases from Lake Mead.
and demand
management
The EVA reconstruction of the gaged
alternatives, for a total of 12 scenarios.
Gila River flow shows that highly
We found that the periodic Gila River
intermittent annual flow series, with
discharges do provide measurable
above-zero flows in less than half of
mitigation of water supply risk. They
all years, can be effectively reconreduce the Colorado River system risk
structed using tree rings (Figure 4).
slightly under all scenarios. Figure
Note the dense cluster of high flows
5 shows the evolution of cumulative
in the early 20th century compared to
probability of storage depletion by
the preceding 300 years. In total, these
2057 for four of the 12 scenarios, and
new reconstructions for the LCRB
the difference when each scenario is
also demonstrate that long-term
run with and without the Gila River
hydrologic variability in the LCRB is
inflows. Furthermore, including the
different enough from the variability
Gila reduces the average shortage
in the Upper Colorado River Basin to
volume per year, increases the storage
justify including the former in system
volume in the system, and reduces
risk assessment as a complement to
the average number of shortages. An
the latter.
important caveat is that the modeling
Performed system response analysis
assumed that 100 percent of the Gila
using the new LCRB reconstructions
as input to a modification of the
Rajagopalan et al. water-balance
“bathtub” model of the Colorado River
Basin
The water-balance model is simple yet
representative of the water resources
system in the basin, and has been
previously used to investigate the risk
of active system storage (60 million
acre-feet; MAF) being depleted under
different scenarios. For this project,
the model setup was modified to
so that variability in LCRB flow
was consistent with the new paleoreconstructions, and so that periodic
inflows from the Gila River could
serve to reduce the releases needed
from Lake Mead. As in a previous

4

River inflows (up to 1.5 MAF/year,
the delivery obligation to Mexico) can
be used to reduce Lake Mead releases.
In practice, due to flow timing and
water quality issues, the substitution
achieved has been much less than
100 percent. But the modeling result
points to the potential for more
deliberate management of Gila
inflows to reduce system risk.

Summary
The project was successful in its
objectives of (1) robustly representing
the long-term hydrologic variability
of the LCRB using multiple statistical
methods, including two promising
new approaches, and (2) incorporating that variability into Colorado
River Basin system risk modeling.
We have found that the variability
of LCRB flows does matter to the
system, and that in particular the Gila
River can have a measurable impact
on system risk due to its periodic,
significant discharges into the
mainstem. Potential follow-up work
could be focused two different tracks:
improving the estimates of natural
flows for both the Gila and the LCRB
mainstem, and investigating the
feasibility of actively managing Gila
River inflows for risk reduction.

Figure 5. Probability of depletion of aggregate Colorado River Basin system storage, as modeled
under four scenarios: reduction in flows of 10 percent (left panel) or 20 percent (right panel)
by 2057 due to climate change; (A) the current (2007) policy for implementing Lower Basin
shortages or (B) a more aggressive policy for implementing shortages; and (all scenarios) basin
demands increasing per Reclamation projections from the 2007 EIS. Each scenario was then run
with and without periodic Gila inflows. In all four scenarios, the Gila inflows measurably reduce
overall system risk.

The WaTer CenTer of Colorado STaTe UniverSiTy

Mapping Irrigated Agriculture in
the Colorado River Basin
Melinda Laituri, Department of Ecosystem Science and Sustainability, Colorado State University
Faith Sternlieb, Research Associate, Colorado Water Institute

T

he Geospatial Centroid at
Colorado State University (CSU)
(gis.colostate.edu) was funded by The
Nature Conservancy (TNC) to develop
a geospatial database of existing
irrigated agriculture in the Colorado
River Basin (CRB). The CRB includes
246,000 square miles that produce
15 percent of the nation’s crops from
approximately 1.8 million acres of
irrigated agriculture—a key component
of consumptive use. This project
has run in parallel with other CRB
projects. The Environmental Defense
Fund funded the Agricultural Water
Governance Mapping project, and the
U.S. Department of Agriculture funded
a research project on agricultural
water, both of which are described in
this issue. We are exploring ways to
integrate the entire suite of publicly
available data collected from these
projects into a singular dataset with the
long term aim of delivering the data
online. Such a dataset is unique in that
data from multiple sources (i.e., U.S.
Bureau of Reclamation [USBR], U.S.
Geological Survey [USGS], National
Agricultural Statistics Service, and
agricultural water supply organizations
of all basin states) and multiple themes,
such as governance, agricultural lands,
and hydrology, will be collected and
organized to create a value-added
dataset of the CRB.
The objective for the TNC project
was to create comprehensive spatial
coverage depicting the extent of
irrigated agriculture, to uniformly map
irrigated crops using existing data from
the USBR, and to identify gaps in the
spatial data. The database produced
for this report juxtaposes the extent
of irrigated agriculture across the
landscape with the size and extent of
the entire CRB.

Table 1. Existing data collected for CRB Irrigated Agriculture mapping. Refer to Demonstration
Mapping for Increasing Agricultural Water Security across the Colorado River Basin, January 2012,
prepared for The Nature Conservancy by Ownby and Laituri for metadata.

Data
Upper Colorado River Basin
Consumptive Use and Loss
Data: Irrigation by Status and
Type1
Irrigated Parcels from
Division 4 (Gunnison),
Division 5 (Colorado),
Division 6 (Yampa/White),
Division 7 (San Juan/Dolores)
Lower Colorado River Basin
Consumptive Use and Loss
Data: Crops (by season)3
Cropland Data Layer4
Salinity Control Projects
(Colorado only)
Salinity thresholds
Irrigated Agriculture
303d listed streams
Selenium Areas6

Source
Bureau of
Reclamation

Colorado
Decision Support
System

Year
Five year reporting cycles:
1990 – 19952
1996 – 2000
2001 – 2005
2005

Bureau of
Reclamation

2005

USDA - NASS
Bureau of
Reclamation
SPARROW5

2010
2009
2009

Environmental
2008
Protection Agency
USGS
1999

1 Irrigation is mapped according to status or type in the UCRB.

Status refers to lands
that are fallow or irrigated. Irrigation type refers to general type: flood, sprinkler, or
unknown. The BoR has generated or obtained new irrigated crop acreage estimates for
all UCRB states for at least one year within each 5-year reporting period.
2 The 1990-1995 irrigated crop layer was an early effort to map irrigation using a
consistent methodology across the UCRB. Since then, BoR has produced crop maps of
only portions of the UCRB that have not been mapped by their respective states.
3 The Lower Colorado River Accounting System (LCRAS) is used to inform the CUL
reports and was developed to refine estimates of agricultural consumptive use, based
on ET and water balance. A GIS database is developed from the processing and
interpretation of remotely sensed data. In addition, BoR collects ground reference
survey data for approximately 12% of irrigated fields in study area, selecting survey
sites in each major irrigated area.
4 The CDL does not include irrigation or seasonal information explicitly.
5 The 2009 dissolved-solids SPARROW (Spatially Referenced Regressions on Watershed
Attributes) model was developed for the Upper CRB as a spatially explicit estimation of
salinity loading. The current SPARROW model uses the 1991 climate year and the BoR
1990-1995 extent of irrigated lands layer.
6 Selenium pollution data are from the USGS report – Areas Susceptible to IrrigationInduced Selenium Contamination of Water and Biota in the Western United States.

Colorado WaTer — noveMBer/deCeMBer 2012

5

their CULRs
in either the
Upper or Lower
Basins. Rather,
the spatial
information
about irrigated
agriculture is
used in analysis
to inform the
accounting for
consumptive
use, presented in
tabular format.
Creating spatial
products from
the USBR data
is inherently
imperfect as
these data are
a snapshot in
time, where
often further
accounting
metrics are
assigned to
Figure 1. Irrigated and agricultural lands of CRB, including the extent of both irrigated and dryland agricultural based on additional
determine the
data collected from 2011.
areal extent of
irrigated
agriculture
from
other data
The database is made up of the
and USBR selenium data for the
sources (i.e., Census of Agriculture) for
following data derived from multiple
Upper Colorado River Basin (UCRB)
an output that is not spatial but tabular.
sources. Base layers downloaded from
were examined. The EPA’s 303d listed
Additionally, the USBR’s accounting of
the National Atlas include the Colorado
streams were also incorporated into the
irrigated agriculture is an estimation
River and its tributaries, the USBR
database.
built upon best available data
management boundary, the boundary
The products created from this research
collected from a variety of sources. In
between the Upper and Lower
include both a query-able ArcGIS
constructing this dataset, the data were
Colorado river basins, state and county
geodatabase and an interactive set of
stitched together across the entire CRB
boundaries, and eight digit hydrologic
PDF maps. In May, a workshop at CSU
and amalgamated and standardized to
units obtained from the USGS National
utilized the projection-based Google
present a holistic snapshot of the CRB.
Water Information System. A spatial
Liquid Galaxy (http://lib.colostate.edu/
and temporal database (Table 1) was
USBR methods of data collection for
services/computers/google-liquidcreated of digital data (1990-2005)
the CULR are different for the Upper
galaxy) to present the results to TNC,
provided by the USBR using the
and Lower basins. In the Upper Basin,
USGS, the Environmental Defense
Consumptive Uses and Losses Reports
states estimate their consumptive
Fund, and CSU. Since completion of
(CULRs) in the Upper Colorado River
uses and losses of CRB water using
this project, additional agricultural
Basin (UCRB). Spatial data were also
methods different from those used
information has been added that
provided by the USBR of irrigation for
by the USBR and between states, so
encompasses dryland agriculture across
the lower main stem of the Colorado
estimates may differ between entities.
the entire basin, including irrigated
River. These data layers were compared
The CULR use USBR methodologies to
agricultural lands (Figure 1).
with other data from USDA—Cropland
estimate consumptive uses and losses
Data Layer (CDL) and data from the
There were several challenges
based on the modified Blaney Criddle
Colorado Water Conservation Board’s
associated with the development of
method for all Upper Basin states with
Colorado Decision Support System
this dataset. The USBR does not create
the exception of New Mexico. The
(CDSS). Additionally, USGS salinity
maps of irrigated agriculture as part of

6

The Water Center of Colorado State University

USBR uses a process to further refine
their statistics on irrigated agriculture
in which data are collected from the
USDA Census of Agriculture (COA)
that is conducted every five years and
state’s annual County Agricultural
Statistics (CAS). In the Lower Basin,
the USBR accounts for use on the main
stem using a “diversion minus flow”
methodology for all water users within
the Lower Basin states, as published
in Water Accounting Reports and the
CULR. Until 2000, the CULR included
irrigated acreage and estimated
consumptive use and losses in the
Lower Basin tributaries. The USBR
recognizes that there are discrepancies

between the various accounting
approaches and are seeking to resolve
these discrepancies in both the Upper
and Lower basins.
To map irrigated agriculture, a common
crop type classification was developed
to map crop types across the entire
basin and to compare against the crop
types from the CDL and CDSS. This
Common Classification was adapted
from the classification procedures
developed for the South Platte Decision
Support System in Colorado (Table 2).
Without the Common Classification,
crop types would be classified
differently between the Upper and
Lower Basins. The data were reclassified

Table 2. Common Crop Classification used for the CRB. adapted from Schneider, Martin, and
Woodward, 2006, SPDSS Memorandum 89.2 – Crop and Land Use Classification Procedures for Year
2001.

Crop
Alfalfa

Characteristics
A flowering plant cultivated as an important forage crop in
Colorado. It usually greens up during April and early May
and is harvested 3-4 times during the growing season that
ends in early October.
Bluegrass/Sod A lawn grass, which comprises less than 2% of total irrigated
area in Water Divisions 4-7 in Colorado.
Sod or turf is grass used to establish lawns. This comprises a
negligible portion of the irrigated areas in Water Divisions
4-7 in Colorado.
Corn
Includes corn used for grain or silage. Planted between late
April to early May and harvested from September through
November. Includes sorghum and sudan.
Cotton
Cotton
Dry Beans
Includes pinto beans, white beans, and others. Planted
between May to early June and harvested from late August to
late September.
Grass Pastures Includes pastures with cultivated grass and hay. It greens up
in spring and early summer
Orchard
May include Ground Cover. Apples, peaches, plums, and
grapes are the major crops grown in orchards in the region.
Small Grains
Includes winter wheat, spring wheat, oats, barley, rye, and
millet. Winter wheat is planted in September of the previous
year and is harvested around early July. Oats and barley are
planted in March or early April and harvested in July.
Vegetables
Includes a variety of crops such as potatoes, squash, onions,
pumpkins, lettuce, spinach, and broccoli.
Other
Includes everything else: Aquaculture, Blueberries, Camelina,
Clover/Wildflowers, Cranberries, Herbs, Hops, Mint, Other
Crops, Rice, Sugarbeets, Sugarcane, Sunflower, Vetch.

Colorado WaTer — noveMBer/deCeMBer 2012

to represent consistency of crop types
across the basin, and assumptions have
been made in re-categorizing data. For
example, the original CDL classification
included 91 different crop types within
the basin that were reclassified for this
project by aggregation (such as pasture,
hay) or exclusion (such as dryland
agricultural crops; crops not found in
the CRB) into the 10 crops types of the
Common Classification System.
Changes are underway with respect
to mapping the CRB irrigated lands.
For example, the USGS is developing
a spatial dataset from the mid to late
2000s of irrigation for the Upper CRB.
This mapping will be used to improve
the outputs from the SPARROW
model, will refine the extent of
irrigation in the Upper CRB by status
and type, and will be used as a baseline
for monitoring change in salinity
loading from irrigation. Also, the USBR
is working on changing procedures for
estimating evapotranspiration in the
UCRB from crop maps combined with
surface weather information to remote
sensing-based energy balance models
for 2006-2010. However, relationships
between crop types will need to be
made explicit to estimate consumptive
water used by agriculture.
Collection of agricultural data for
the CRB has continued after the
completion of the TNC project. Efforts
to include recent, available data from
various entities are essential to creating
a current and holistic database of the
CRB. Governmental organizations
in partnership with universities are
developing classification techniques
utilizing remotely sensed data with the
long term aim of creating real-time
representation of irrigated agriculture
in the CRB. If you are interested in
learning more or would like to include
your data in the CRB database, please
contact Melinda Laituri,
[email protected].

7

Mapping Agricultural Water Governance
in the Colorado River Basin
Faith Sternlieb, Ph.D. Candidate, Geosciences, Colorado State University
Melinda Laituri, Department of Ecosystem Science and Sustainability, Colorado State University

Introduction
Emerging cooperative arrangements
for water use, development, and
conservation in the Colorado River
Basin (CRB) indicate changes in
both the political and environmental
climate. These arrangements are
geographically taking shape at the
intersections of hydrologic, political,
and social boundaries. Water agencies
and organizations (e.g. private/
public, national/local, governmental/
non-governmental, etc.) are struggling
with ways to address these complexities
and, as a result, are creating new rules
and arrangements that necessitate
new datasets and visualization
techniques. Agricultural (Ag) water
supply organizations are central
actors in new arrangements because
they hold 70-80 percent of the water
rights. In order to better understand
these new rules and arrangements
and how they affect Ag water supply
organizations, the development of a
geospatial database will facilitate the
analysis of linkages between sectors
and political jurisdictions at multiple
scales that intersect with hydrologic
adaptations throughout the basin.
These intersections will identify
locations where strategic arrangements
with Ag already exist and where new
arrangements may flourish.
This paper describes the process,
evolution, and continued development
of a basin-wide geospatial database
describing agricultural water
governance (complimentary to
the project “Addressing Water for
Agriculture in the Colorado River
Basin,” this issue). For the purposes of
this article, Ag water governance is the
interface between Ag, hydrological,
and human systems where formal
and informal policies, rules, and

8

Figure 1. This map layout demonstrates U.S. Federal and Tribal Lands in the Colorado River Basin
overlaid on a topographic basemap.

practices shape human interaction
with the environment. The Colorado
River Basin Agricultural Water
Governance database is an effort to
collect data about governance and
heighten awareness about the changing
circumstances of decision-making
about water for Ag in the CRB. The aim
of this project is to compile data for the
entire CRB in one place to provide an
online clearinghouse that will inform
stakeholders, water users, and decision
makers about Ag water in the basin.

Geography
The CRB encompasses seven U.S.
states (Arizona, California, Colorado,
Nevada, New Mexico, Utah and
Wyoming), two Mexican states (Baja
California and Sonora), and at least
43 U.S. tribes (not including Mexican
indigenous tribes). The Colorado River
boundary in Figure 1 is defined by the

Bureau of Reclamation. The length of
the Colorado River when measured
from the Green River, Wyoming is
1,700 miles (2,736 km) long or 1,400
miles long when measured from Rocky
Mountain National Park (43°09’13”N
109°40’18”W) to the mouth of the Gulf
of California otherwise known as the
Sea of Cortez (31°39’N 114°38’W). The
drainage basin encompasses an area
of 246,000 square miles (637,137.08
square km). The hydrology of the
river is highly controlled through
a series of dams and reservoirs
which harnesses water for energy,
consumptive, and non-consumptive
purposes in the basin. Ninety percent
of native in-stream flows originate from
snowmelt of the Green (Wyoming),
Gunnison and San Juan Rivers
(Colorado). The current average flows
are estimated at 14.7 million acre feet,
and the total storage capacity is at
60 million acre feet. The majority of

The Water Center of Colorado State University

Table 1. Federal agencies and their classifications under the Department of the Interior (DOI) that
own and administer land in the Colorado River Basin: Bureau of Land Management (BLM), Bureau of
Reclamation (BOR), Department of Defense (DOD), the Forest Service (FS), Fish and Wildlife Service
(FWS), and the National Park Service (NPS).

DOI
Federal Lands Classification
Area in % of Land in
Agencies
Miles2 the CRB*
BLM
National Conservation Areas, National
82,920 34%
Monuments, National Recreational
Areas, Public Domain Land, Wilderness,
Wilderness Study Areas
BOR
1,173
< 1%
DOD
Air Force, Army Corps of Engineers, Marine 5,596
2.3%
Corps, Navy
FS
National Forests, National Recreation Areas, 47,014 19%
Wilderness, Wilderness Study Area
FWS
National Wildlife Refuges, Wilderness
3,739
1.5%
NPS
National Historic Parks, National Historic
8,805
3.5%
Sites, National Memorials, National
Monuments, National Parks, National
Preserves, National Recreation Areas,
Wilderness, Wilderness Study Areas
TOTAL
149,247 60.8%
* These percentages are based on the Bureau of Reclamation Colorado River
Basin management boundary, obtained from the BOR Lower Basin Office, which
includes the Mexican portion of the basin. The area is estimated to encompass
246,000 mi2.
Table 2. Due to the complexity of overlapping jurisdictional boundaries in the Colorado River Basin,
identifying boundary types and governance layers clarifies how decisions are made and who is
affected by those decisions.

Boundary Type
Physical

Governance Layer
Hydrologic Unit Code

Hydrographic
Administrative

Legislative
Judicial
Political

Sector

Agricultural Water
Supply Organization

outflows include trans-basin diversions
(San Juan Chama, Central Utah Project,
NCWCD/Big-Thompson, Colorado
River Aqueduct/All American Canal,
Fryingpan/Arkansas) and evaporation
from major reservoirs.

Description
Based on natural drainage systems
defined by the National Hydrology
Dataset (USGS)
Based on drainage basin delineated
by each state and tribe
Based on federal, state and tribal
laws and policies
Based on U.S. Federal, District and
Appellate Court system
Based on governmental jurisdictions (federal, state, tribe, county,
municipality, city)
Based on state statute and organizations’ bylaws
The majority of land (60.8 percent) in
the CRB is owned and administered by
the U.S. federal government and under
the jurisdiction of the Department of
the Interior (DOI) of federal agencies
(Figure 1, Table 1).

Colorado WaTer — noveMBer/deCeMBer 2012

Tribal lands constitute 16 percent or
40,462 square miles (104,797 square
km) of the CRB and are federal lands
that are overseen by the Bureau of
Indian Affairs (BIA) but administered
independently as sovereign nations
by the respective tribal governments.
Although farmers and ranchers
depend on the federal lands for grazing
their livestock, all of the farming and
Ag production takes place on the
remaining private lands. The federal
agency that has the largest presence in
the CRB for water supply is the Bureau
of Reclamation. In light of their water
management responsibilities, the
bureau holds the least amount of land
(less than one percent).

Geospatial Database
Development
The geospatial database is currently
under development. Much of the
spatial data for the CRB is accessible
online but is dispersed on the internet
through various non-governmental
organizations and governmental
agencies. In addition, some of the
data may or may not be available for
download and/or viewed. Challenges
in creating such a geodatabase include
data collection and compilation from
multiple sources (some of which
are private and hold proprietary
information) at multiple scales and
for different purposes. Compounding
the challenges are the different types
of data such as satellite imagery, paper
maps, historical records, and field
data collection, as well as techniques
used to collect data including global
positioning systems, surveying
instruments, and photogrammetry,
among others. Finally, data collection
at a coarse versus fine resolution,
disparate standards for metadata, and
minimal coordination in data collection
efforts make it difficult to mainstream
datasets.
The spatial data is organized in
“governance layers.” which describe
physical and administrative
jurisdictions as well as jurisdictions

9

that are socially and/or hydrologically
organized. Governance layers are
defined by two key components: 1)
mandated or naturally occurring
geographic boundaries and 2) decisions
made based on those boundaries. Each
governance layer may be represented
in a geospatial database by a geospatial
file. Each jurisdiction is governed by
distinct rules, actors, and cultural,
social, and behavioral codes. By
overlaying governance layers in a
geographic information system (GIS),
jurisdictions overlap, affecting multiple
levels of decision-making. Governance
layers describe the complexity of water
governance in the CRB because they
demonstrate overlapping organizations
and arrangements as well as the norms
and behaviors of actors who have
different and sometimes opposing
claims in the use, management, and
development of water resources.
Special districts such as Ag water
supply organizations are central to
water development in the CRB. Such
service and supply organizations
can be classified in two types: 1)
private owned by shareholders, and
2) public, which are federal, state, or
quasi-governmental. Private Service
and Supply Organizations are water
utilities, mutual water companies,
carrier ditch companies, and mutual
ditch and irrigation companies. Public
Service and supply organizations are
municipalities, irrigation districts,
conservancy districts, conservation
districts, reclamation districts, water
control districts, fresh water supply
districts, and municipal water districts.
“Water supply organizations such as
irrigation and conservancy districts
are formed primarily to raise revenue
(by property taxation and bond sales)
and to construct and operate irrigation
projects. Some [organizations]
contract with the federal government
to administer government-financed
reclamation projects” (Getches 2009, p.
453).
Data collection has become more
prevalent, and an increasing number

10

Figure 2. Irrigated and agricultural lands overlaying Ag water supply organizations in the CRB.
Ag water supply organizations represented are those that have: a) contracts with the Bureau of
Reclamation, b) subcontractors for Colorado River water through Bureau projects (e.g., irrigation
districts that have subcontracts for Central Arizona Project water), or c) entities responsible for
water supply through state legislature (e.g. Water Conservancy Districts in Utah).

of organizations are collecting data
and producing reports, resulting in
fragmented datasets. This is especially
true in the CRB. Data have been
collected continuously from different
governmental agencies, CRB states,
Ag water supply organizations, and
non-profit organizations, as well as
local public and private entities. This
data collection exercise has been
conducted in parallel with The Nature
Conservancy-funded project discussed
in this issue. Geospatial data includes:
•

Hydrologic boundaries defined
both by state and by hydrologic
unit

•

Boundaries for Ag water
jurisdictions within the basin
including but not limited to Bureau
of Reclamation projects (including
infrastructure), irrigation
districts, water conservancy
districts, conservation districts
(relating to water management
and administration), water users
associations, and private irrigation
and ditch companies

•

Boundaries that demonstrate
environmentally sensitive areas
such as salinity control areas,
wild and scenic stretches of the
Colorado River and tributaries, and
areas where endangered species
are of concern or are actively being
protected

Spatial data in the database also
includes governance layers describing
Mexican jurisdictions. In addition, we
are in the process of integrating data on
Ag and irrigated lands collected as part
a project of The Nature Conservancy in
collaboration with CSU (see article on
Ag lands in the Colorado River Basin in
this issue) and the Geospatial Centroid.
Data on Ag water supply organizations
together with Ag lands are being
compiled to create one comprehensive
geospatial database for the CRB (Figure
2).

Future Research
The Agricultural Water Governance
project on CRB and The Nature
Conservancy’sproject on irrigated

The Water Center of Colorado State University

Ag in the CRB combine two datasets
that have never before been created.
To demonstrate this dataset, an
interactive geospatial database is under
development. The aim of compiling this
dataset is to capture Ag water supply
organizations that use Colorado River
water and deliver the information
through a basin-wide database
accessible to water users. The breadth,

depth and purpose of the database are
dependent in part on the contributions
and sharing of information and data by
Ag water users in the CRB and will be
useful to them as the water landscape
in the CRB changes. Complimentary
information about Ag water supply
organizations including water rights,
contracts, and federal and state policies
will be collected and compiled to add

value to the dataset. Representing this
information spatially will complement
the water quality/availability data that
has been collected, processed, and
made available. The best available data
has been collected. If you are interested
in more information about this project
or would like to include your data in
this database, please contact Faith:
[email protected].

Upper Yampa Scholarships Announced
The Upper Yampa Water Conservancy District John Fetcher Scholarship provides financial assistance to a committed and
talented student who is pursuing a water-related career in any major at a public university within the state of Colorado.
Congratulations to this year’s scholarship recipients, Tyra Monger and Benjamin Von Thaden.

Tyra Monger

Benjamin Von Thaden

“Being raised on
a cattle and hay
ranch outside
of Hayden, I
understand the
value of water.
I also have
understood and
been schooled
in the value of
being a great
steward of the
land/water. Once
I have graduated
from Colorado
Mesa University, I am hoping to find a career
working in Colorado. Being an outdoors person
and being able to maintain the environment
have been my lifelong dreams. Currently I am an
Environmental Science/Technology major with
a Watershed minor. I believe that these programs
will become an ever more important field of
study to our country and economy. One of the
hopes for my future is to return to Routt County
to volunteer to further nourish 4-H programs.
4-H provides skills to young adults that can be
used throughout their lives as they fulfill their
careers. I hope to also be able to help on my
family ranch.”

“I feel very privileged to have been raised in Routt County and I
can definitely see myself living and working in the Yampa River
Basin in the future. In 2009 I participated in a Tamarisk removal
trip on the Yampa River through Dinosaur National Monument.
The trip was very eye opening for me and I would like to do more
work, and possibly research, in the fight against invasive species
such as Tamarisk and Russian Olive in the Colorado River Basin.
After I graduate I plan on joining Engineers Without Borders and
traveling around South America to help create better access to safe
drinking water and improve sanitation. When I was a sophomore at
the Lowell Whiteman School I traveled with the school to Bolivia for
my foreign trip. As a service project my group installed a water filter,
utilizing rocks, gravel, sand, clay, and silt, to provide safe drinking
water to a small village close to Rurrenbaque, Bolivia, in the Amazon
Basin. It was an amazing experience
to help these less-fortunate people by
providing safe drinking water, and I feel
I have an obligation to participate in
similar projects in the future, hopefully
on a larger scale. I have learned that
water-related problems are often times
very complex and do not have a simple
solution, but require collaboration
between many groups and industries.
While I am not sure of the exact
direction that my career will take, I am
very excited about having a career in the
water industry.”

•
•
•
•

University: Colorado Mesa University
Anticipated Graduation: 2014
Major: Environmental Science and Technology
Areas of Interest: Watershed

•
•
•
•

University: Colorado State University
Anticipated Graduation: 2013
Major: Watershed Science
Areas of Interest: Water quality monitoring, snow hydrology,
water allocation, climate change, and water-related recreation

Colorado WaTer — noveMBer/deCeMBer 2012

11

Addressing Water for Agriculture in the Colorado
River Basin: A Project Progress Report
Peter Leigh Taylor, Department of Sociology, Colorado State University
MaryLou Smith, Policy and Collaboration Specialist, Colorado Water Institute
Julie Kallenberger, Assistant Regional Water Coordinator, Colorado Water Institute
Faith Sternlieb, Research Associate, Colorado Water Institute
Reagan Waskom, Director, Colorado Water Institute

C

olorado State University’s
Colorado Water Institute (CWI)
is spearheading a U.S. Deartment
of Agriculture-funded research
project on water for agriculture in
the Colorado River Basin (CRB).
Carried out in partnership with the
seven CRB land-grant universities
—Colorado State University,
University of Arizona, University
of California, University of Nevada,
New Mexico State University, Utah
State University, and University of
Wyoming (Figure 1)—we want to
find out what farmers, ranchers, and
water managers are thinking about
the current and future status of their
agricultural water. Through this
project, we hope to identify ways in
which land-grant universities can

better assist agricultural water users
and managers with the challenges
they are facing.
Here, we briefly report on our
progress with the research, which
includes in-depth exploratory
interviews and survey and mapping
activities.

The Interviews
We have completed in-depth
telephone interviews with more than
sixty farmers, ranchers, and water
managers in all seven CRB states. Our
other university partners helped us
identify areas of high significance for
agricultural water within each state
and assisted us in contacting potential
interviewees. We asked interviewees
open ended questions about what

they felt were the main pressures,
if any, on agricultural water, how
farmers were responding, how they
saw the future of agricultural water,
and how land-grant universities might
help. Although we are in the process
of analyzing the rich information
from these discussions, below we
provide some preliminary thoughts
on what we have learned.

The Survey
The project team will be
administering an online survey of
farmers and ranchers in selected
counties of Colorado and Arizona
who use Colorado River water. The
survey will address similar topics
as those covered in the interviews,
but will gather information from a

The CRB Land-Grant Universities Team at a February 2012 Workshop in Tucson.

Photo by Sam Fernald

12

The Water Center of Colorado State University

districts, water users associations,
and private irrigation and ditch
companies
•

Figure 1. Addressing Water for Ag project team members’ Land Grant Universities

broader audience in order to help
formulate collective solutions to keep
irrigated agriculture viable in the
Colorado River Basin. The survey
seeks to:
(a) Identify what CRB agricultural
water users think about the current
and future state of their water
supplies and production activities
(b) Identify and compare the
attitudes, beliefs, and perceptions
held by agricultural water users
towards the changes and pressures
they are/are not facing with their
water supplies, changes in water law
and policy, and how to meet future
water demands
(c) Gather data on agricultural
producers’ interest and involvement
in temporary and permanent
agriculture water transfers and water
banks
(d) Identify how agricultural
producers work cooperatively
with other agricultural and
non-agricultural stakeholders
(e) Identify how land-grant
universities can better assist farmers
and ranchers with the challenges

they are facing, or will be facing with
regard to their agricultural water
(f) Gather ideas for projects,
partnerships, and other initiatives to
work with agricultural producers to
help address the challenges they are
facing with regard to their water and
operations

The GIS Mapping Activities
The project team conducted a
mapping exercise in December 2011
with approximately 40 agricultural
representatives from the CRB. A
geospatial database is being created
to help us better understand how
agricultural water is administrated
and managed in the seven CRB states.
Data collected includes:
•

Political jurisdictions including
counties, states, tribal lands,
counties, and municipalities

•

Hydrologic boundaries defined
both by state and by hydrologic
unit

•

Agricultural water jurisdictions
within the basin including Bureau
of Reclamation projects, irrigation
districts, water conservancy
districts and conservation

Colorado WaTer — noveMBer/deCeMBer 2012

Environmentally sensitive areas
such as salinity control areas,
designated wild and scenic
stretches of the Colorado River
and tributaries, and areas where
endangered species are identified
as of concern or are actively being
protected

Maps have also been an integral part
of the interview process. With help
from water leaders in each state, we
created maps to help us locate areas
where agricultural water is especially
important and where we needed to
interview individuals and key water
organizations’ representatives (see
Figure 2 for interviewee locations).
Though the interviewees’ identities
are confidential, during the interviews
we referenced digital maps showing
local political jurisdictions, waterways
and other features to help us locate
our discussion in the complex
geographic space occupied by the
interviewees.
All of the base maps were created
from a comprehensive geospatial
database of the CRB that is being
developed under the direction of
Melinda Laituri (see both articles on
agricultural water governance and
agricultural lands in this issue).

Preliminary Results from the
Interviews
Agricultural water users across the
CRB are of course, very diverse.
They operate across geographical
contexts that vary from Upper to
Lower Basin, high-altitude to sea
level areas, and from forested to
semiarid regions. They engage in a
wide range of agricultural activities,
from cattle ranching and cropping
of pasture, alfalfa, and small grains,
to high value vegetables, fruits, nuts,
and more. Agricultural water users

13

agriculture and
from energy,
environmental,
recreational,
and municipal/
industrial sectors.
Many respondents
have talked about
the need for
storage to manage
effectively for
multiple use and
conservation but
often express
concern about
the barriers
posed by negative
public views
of storage and
time-consuming
and expensive
permitting
processes.
Conjunctive
Figure 2. Pushpins indicate where interviews were conducted with
management
agricultural water managers, users, and their respective agricultural
water supply organizations.
of surface and
groundwater
poses
increasingly
and managers operate under the
complex
problems
of
water access
1922 Colorado River Compact and
and
management.
Many
have
the Law of the River, yet each state
commented on how government
provides distinctive frameworks for
regulatory frameworks, especially the
agricultural water use, management,
Endangered Species Act, the National
and transfer. Agricultural water users
Environmental Protection Act, the
and managers operate in a complex
Clean Water Act, and health and
set of organizational contexts, from
safety regulations, have fundamentally
individual surface water diverters
changed not only how water is used,
and groundwater users to ditch
but agricultural production itself.
companies, irrigation districts,
Many farmers have expressed concern
and water conservancy districts.
about the need to strengthen public
Nevertheless, agricultural water users
understanding of the importance of
and managers report a number of
agriculture for a secure and healthy
common challenges (though their
food supply. Many also have observed
experience of them is shaped by
that the key role irrigated agriculture
geographic location, the history and
plays in creating ecological and
seniority of their water rights, the
amenity values is not well understood
type of agriculture and ranching, the
by many in the environmental and
proximity of urban areas and other
recreation communities. Others
competing water users, etc.).
have remarked on the increasingly
These common challenges include
litigious environments in which
uncertain water supplies, extended
discussions of water are occurring
drought and the threat of climate
and suggested that more real progress
change, and competition and conflicts
can be made when people can stay out
with other water users within
of court. Our interviewees have also

14

spoken, often with great poignancy,
about uncertain futures for family
farms and agribusinesses as younger
generations choose not to continue in
agriculture. Numerous interviewees
have spoken of farming’s future as
one integrated with growing cities,
with fewer traditional operations and
many smaller “amenity” farms. Some
farmers spoke of selling parts of their
land and water rights to developers
or even acting themselves as
development investors, with returns
reinvested in agriculture elsewhere or
in helping secure their retirement.
It seems clear that agricultural
water users are not affected the
same way by the challenges facing
them today. Many interviewees
describe themselves as positioned
to move ahead and either surmount
these challenges or adapt to them
in new and productive ways. These
well-positioned users of agricultural
water are found in all parts of the
CRB represented by our interviews.
Yet agriculture and agricultural
water is described as strongest where
geographic and climatic conditions
allow highly productive agriculture
with year-round, high-value
commercial cropping. Water users
with the most senior water rights
are more cushioned from the
uncertainties of an intensively used
river and of supplies threatened by
extended drought and predicted
climate change. Though having
urban areas nearby generally
results in significant pressures from
non-agricultural water demands,
transportation and communication
infrastructure also mean lower
costs of production and marketing.
Significantly, it is in these areas that
interviewees spoke more consistently
of new generations entering farming,
ranching and related agribusiness.
Agricultural water users working in
geographical areas where climatic and
soil conditions pose higher obstacles
to productivity, shorter growing

The WaTer CenTer of Colorado STaTe UniverSiTy

seasons, and greater isolation from
markets face special challenges in
adapting to new water pressures.
More of these respondents spoke
poignantly about their sense of the
threats to a traditional farming way
of life, as their children seek futures
outside of agriculture. Yet these
interviewees are clearly not giving up;
on the contrary, they express deep
commitments to what is in many
cases, multi-generational investments
in their land, water and agricultural
way of life. They also express a strong
commitment to providing food for
our society, and their concern for
national food security. Moreover,
they are working hard to develop
innovative ways to protect their water
and their communities.

participants in successful experiences
have spoken of what can be achieved
with key visionary leaders, a focus
on common interests of all parties
in healthy local economies and
riparian ecologies, willingness of all
user groups to compromise, and a
commitment to generating concrete
results quickly, even if on a small
scale. Other innovative responses
reported by interviewees include
diverse groundwater recharge
programs, formal and informal
water banking, and a range of leasing
mechanisms. Numerous interviewees
have reported on innovative
approaches to planning storage as
a key to developing secure future
supplies of water for multiple uses,
including agriculture, environmental,
and recreational uses.

Indeed, interviewees throughout the
CRB have talked about innovative
What Needs to be Done?
strategies they are developing to
Our interviewees have spoken of
overcome or adapt to pressures on
possible paths to a positive future for
agricultural water. In many areas,
agricultural water. They suggest that
as in California, Arizona, and
the broader public might be helped
Colorado, agricultural water users
to better understand the importance
and managers have embarked on
of irrigated agriculture, not just for
new agreements with large urban
securing high quality and safe food
water users to develop water supplies
for our nation, but also for creating
for multiple objectives, including
significant environmental and
urban, environmental, recreation, and
amenity values. As one Wyoming
agriculture. Several water managers
rancher put it, “This is an oasis in the
have described their organizations’
services to multiple user
groups and their need to
plan for more urban and
municipal demands while
maintaining support for
agriculture. In several
areas, such as Wyoming,
Colorado, and New Mexico,
multi-stakeholder forums and
organizations have formed
to try to manage conflicting
claims and perspectives on
water by bringing agriculture,
environmental, recreation,
and other groups to the
negotiating table. These
initiatives are not easy and
have had mixed results, but
The Water for Agriculture Interview Team at CSU.

high desert. But God didn’t make the
oasis. It’s man-made. It takes lots of
water, diverted regularly in almost
impossible quantities to keep it that
way.” Interviewees remarked that
regulatory frameworks could better
recognize both the continuing need
for a viable agriculture throughout
the CRB as well as its obstacles.
Competing water users/stakeholders
could develop more effective ways to
negotiate based on understanding if
not agreement with other perspectives
and the need for a strong agriculture
in the future.

What is the Role of
Land-grant Universities?
Most interviewees have expressed
positive views of land-grant
universities. They speak of the
Extension agents who help them
improve efficiency of irrigation
technology and water management,
introduce new seeds, and implement
better soil practices. Interestingly,
although most of our open-ended
questions about the agricultural
water community’s challenges
stimulated discussion of issues that
are largely political, economic, social,
and cultural in nature, relatively
few respondents had experience
with universities helping with these
issues. This suggests to us
that land-grant universities
have an opportunity to
bring to bear new kinds of
social science research and
outreach on the problems
facing agricultural water users
and managers, in addition
to their traditional strengths
in natural science and more
technical disciplines.

Photo by Bridget Julian

Colorado WaTer — noveMBer/deCeMBer 2012

Results from the Addressing
Water for Agriculture in the
Colorado River Basin project
will be summarized and
posted on the project website
(www.CRBagwater.colostate.
edu) in the spring of 2013.

15

Courtesy of Denis Reich

30 Years of Salinity Programming—What
Does it Mean for the Colorado Today?
Denis Reich, Water Resources Specialist, CSU Extension, Colorado Water Institute

F

or anyone who’s driven past the
Bookcliffs desert near the Grand
Junction airport in the spring, salt is
a common sight. The streaks of white
are sometimes as thick as heavy frost
on the adobe hills. This is Colorado
River Basin salt at its most visible. The
less obvious behind-the-scenes story
is soil borne salt’s contamination of
our most famous Western river. The
response, the Colorado River Salinity
Control Program, has been one of the
most involved yet successful water
quality programs in United States
history.
With an average of about 10 inches of
precipitation per year, the tight clay
soils of Western Colorado’s arid agricultural valleys—such the Grand and
Uncompahgre—see few downpours
or sustained showers. This prolonged
lack of water has historically not been
enough to penetrate below the surface
and flush the resident mineralized

salts—the same that surface in the
adobes each spring—out of the clay
subsoil and downstream.
With the arrival of Europeans to
Western Colorado, irrigated agriculture effectively raised the average
application of water from a few inches
to a few feet. As canals and headgates
were installed, the desert bloomed.
Less dramatic were the millions of
tons of otherwise dormant salt that
irrigation water, percolating deep
into the soil, began quietly releasing
into rivers. It took a few decades,
but once reclamation activities (e.g.,
reservoir filling and increased water
availability) peaked in the 1960s
downstream users in the lower basin
began to notice.
By 1970 Colorado River users
from the United States and Mexico
were raising concerns over salinity.
Levels of 8001 ppm (as TDS) and

higher were becoming the norm in
California and Arizona irrigation
water, rendering it harmful to
many crops. The formation of the
Environmental Protection Agency
and a fear of being regulated with
state-line limits encouraged the seven
basin states to work with federal
agencies to draft special salinity
legislation for the Colorado River.
In 1974, the Colorado River Basin
Salinity Control Act was passed by
Congress.
The act was amended several times
(1984, 1995, 1996, and 2008) and now
exists as the Colorado River Basin
Salinity Control Program, or “Salinity
Program.” The Salinity Program is a
unique and successful collaboration2
between the Department of Interior
(Bureau of Reclamation, Bureau
of Land Management, and the
Geological Survey), the Department
of Agriculture (Natural Resources

1 Drinking water typically has <500 mg/L TDS and Seawater >30,000 mg/L TDS. Most crop damage starts to occur once water in the

root zone reaches 700 mg/L TDS or higher – this is often a function of soil and water salinity.

2 There are three stakeholder groups that manage and inform the Salinity Program: the Salinity Forum—the basin states

representatives; the Federal Advisory Committee—where the forum and federal agencies consult on federal salinity expenses; and
the technical workgroup that advises the two policy-making groups.

26

The WaTer CenTer of Colorado STaTe UniverSiTy

Figure 1. Flow adjusted (LOWESS curves) salinity loads from various gages on the Colorado River in Colorado showing the impact of the Salinity Program on
levels of dissolved salt (TDS). Water Years 1986 to 2003.

Courtesy Leib and Bauch, USGS Scientific Investigations Report 2007-5288

Conservation Service), the Basin
States, and most importantly private
landowners voluntarily participating
in cost share and incentive payments.
In 2010 the Grand Valley Unit of
the Colorado River Salinity Control
Program achieved its target of 132,000
tons per year of salt prevented

from reaching the river through
on-farm irrigation improvements.
This represents 30 years of sustained
effort on the part of Colorado’s
Natural Resources Conservation
Service (NRCS) and key partners
like Reclamation. Recently retired
Assistant State Conservationist Frank

Colorado WaTer — noveMBer/deCeMBer 2012

Riggle has had more experience
than most when it comes to on-farm
salinity control.
“The Salinity Program is unique,” says
Riggle. “I don’t think there’s another
water quality program anywhere that
has seen this amount of work done
across such a large area for this long

27

Mt Garfield of the Bookcliffs stands over the salty adobe hills of the Northern Grand Valley. The
orchards and vineyard owners of the Palisade area and East Orchard Mesa have been early adopters
of Salinity Program irrigation improvements that prevent thousands of tons of salt reaching the
Colorado River each year.

Courtesy of Denis Reich

a period with such a significant and
measureable impact. Quite a feat,”
he continues, “for a river the size
and magnitude of the Colorado” (see
Figure 1). The Program’s success has
since become a model for public/
private partnerships tackling large
scale natural resource problems.
In addition to the nonpoint source
problem, some of the larger point
source salt problems have also been
tackled by the program. Natural
saline springs such as those used to
feed the Glenwood Hot Springs Pool
are the major salt contributors to the
river. At the point of the program’s
inception, nearly 10 million tons of
dissolved salts were passing annually
below Hoover Dam. The Salinity

Program has traditionally focused on
mitigating the agricultural portion
of this load. Irrigation on the eastern
edges of the Colorado Plateau is
responsible for almost half of the salt
contributions to the system.3
The largest point source project
completed so far is the Reclamation
owned and operated deep well
brine injection system near Paradox,
Colorado. It is estimated that the
Paradox injection well project
successfully prevents approximately
110,000 tons of salt per year from
entering the Colorado River system
by capturing shallow saline groundwater that is tributary to the Dolores
River and disposing of this brine over
14,000 feet below the surface into a

geologically confined layer. However,
the injection well is now approaching
or even exceeding its design life,
and the receiving zone is close to
full, which is reflected in increasing
pumping pressures needed to bury
the offending water. Whether to drill
a second well in a new location or
try a new strategy such as membrane
treatment and evaporation ponds is
under consideration via an alternatives NEPA analysis being performed
by Reclamation.
In a sense the Salinity Program is now
at a crossroads. “The low hanging
fruit has already been picked,” reflects
MaryLou Smith of the Colorado
Water Institute. Smith is a subcontractor with URS Engineering on a

3 The Environmental Protection Agency has identified that 62 percent of the salt load contributions into Hoover Dam are from

natural sources.

28

The WaTer CenTer of Colorado STaTe UniverSiTy

new multidisciplinary project,
”Comprehensive
Planning Studies
for Salinity
control measures
in the Upper
Colorado River
Basin.” Working
with URS
Engineers under
the leadership
of Dave Merritt,
Smith is interviewing farmers
and identifying
barriers to user
participation
in remaining
cost effective
salt control
projects. “By
learning more
about what is
preventing some

farmers and irrigation companies
from participating in the Salinity
Program, administrators will have the
opportunity to tweak the program for
improved impact,” says Smith.
The rising cost of salt control clearly
underlies many of the obstacles to
participation. “Western Colorado
agricultural producers and water
users have benefitted from the Salinity
Program, but moving forward in
the era of financial constraints is
quite a challenge” observes Dave
Kanzer, Colorado River District
Senior Water Resources Engineer
and Salinity Program workgroup
member. “Therefore, we anxiously
await results from the ‘planning
studies’ project to help us improve the
implementation and success rate of
the Salinity Program. It’s a program
that is essential to wise water use in
the Upper Colorado River basin,”
concludes Kanzer.

Steve Gunderson, Director of the
Water Quality Control Division at
the Colorado Department of Public
Health and Environment agrees. “The
Salinity Program has not outlived its
usefulness,” says Gunderson. “The
Lower Basin states are still very much
invested in Salinity mitigation and
in the Upper Basin we have come to
depend on the multiple benefits of the
Salinity Program such as Selenium
control.” In a sense selenium is the
new salinity. Found with mineralized
salt in some shale soils, it’s highly
concentrated in Western Colorado,
particularly the Lower Gunnison
Basin. It contaminates the river at
very low concentrations, not harmful
to crops or humans, but surprisingly
destructive to many forms of aquatic
life, some of which are endangered.
Thanks in part to salinity program
funded control projects, concentrations of dissolved selenium are
dropping towards, and in some cases
even below, the state standard of 4.6
parts per billion.
Thanks to its continued success,
the Salinity Program continues to
be a benchmark for water quality
programs across the United States and
around the globe. While funding to
other natural resources collaborative
processes are particularly vulnerable
given the current economic climate,
the Salinity Program has found ways
to adapt and remain viable in spite of
these pressures. In 2013 there will be a
celebration in Grand Junction for the
Grand Valley exceeding its target for
removal. It should be the first of many
to come.

Acknowledgements

Bad experiences with the first pivot sprinklers in the 1980s have delayed adoption of newer
technologies among row-crop farmers in the salt affected areas of the Upper Colorado. This producer
adjusts an emitter on a more modern pivot, which runs on lower pressures—around 30 psi—
producing smaller droplet sizes, which greatly improves infiltration and crop water uptake.

Thanks also to Travis James of NRCS
in the Salt Lake Reclamation office,
and Terry Stroh and Dan Crabtree
of the Bureau of Reclamation Upper
Colorado Regional Office in Grand
Junction for their assistance with this
article.

Courtesy of Denis Reich

Colorado WaTer — noveMBer/deCeMBer 2012

29

USGS Summer Intern Program
None.

USGS Summer Intern Program

1

Category
Undergraduate
Masters
Ph.D.
Post-Doc.
Total

Student Support
Section 104 Base Section 104 NCGP
NIWR-USGS
Grant
Award
Internship
7
0
1
4
1
1
4
1
0
0
0
0
15
2
2

Supplemental
Awards
5
5
3
0
13

Total
13
11
8
0
32

1

Notable Awards and Achievements
• Kurt Fausch Presenter at NDSU Distinguished Water Seminar
• Upper Yampa Scholarships Announced

Awards and Achievements

Kurt Fausch Presenter at NDSU Distinguished Water Seminar
Dr. Kurt Fausch of the Colorado State University Department of Fish, Wildlife, and Conservation Biology
was invited to present the 2nd Distinguished Water Seminar at North Dakota State University (NDSU) on
Feb. 21, 2012, titled, “Linked for Life: The importance of sustaining hidden connections for conservation in
streams.” A main focus of his talk was how human impacts like nonnative fish invasions and riparian grazing
alter key linkages between streams and riparian zones that sustain not only stream fish but also birds, bats,
lizards, and spiders in the riparian zone. The invited seminar was sponsored by the North Dakota Water
Resources Research Institute, the NDSU Environmental & Conservation Sciences Graduate Program, and the
Department of Biological Sciences. For more information, visit
http://www.ndsu.edu/wrri/Image/Flyerfinal.pdf.
Upper Yampa Scholarships Announced
The Upper Yampa Water Conservancy District John Fetcher Scholarship provides financial assistance to a
committed and talented student who is pursuing a water-related career in any major at a public university
within the state of Colorado. Congratulations to this year’s scholarship recipients, Tyra Monger and Benjamin
Von Thaden.
Tyra Monger
University: Mesa State College
Anticipated Graduation: 2014
Major: Environmental Science and Technology
Areas of Interest: Watershed
“Being raised on a cattle and hay ranch outside of Hayden, I understand the value of water. I also have
understood and been schooled in the value of being a great steward of the land/water. Once I have graduated
from Colorado Mesa University, I am hoping to find a career working in Colorado. Being an outdoors person
and being able to maintain the environment have been my lifelong dreams. Currently I am an Environmental
Science/Technology major with a Watershed minor. I believe that these programs will become an ever more
important field of study to our country and economy. One of the hopes for my future is to return to Routt
County to volunteer to further nourish 4-H programs. 4-H provides skills to young adults that can be used
throughout their lives as they fulfill their careers. I hope to also be able to help on my family ranch.”
Benjamin Von Thaden
University: Colorado State University
Anticipated Graduation: 2013
Major: Watershed Science

Notable Awards and Achievements

1

Areas of Interest: Water quality monitoring, snow hydrology, water allocation, climate change, and
water-related recreation
“I feel very privileged to have been raised in Routt County and I can definitely see myself living and working
in the Yampa River Basin in the future. In 2009 I participated in a Tamarisk removal trip on the Yampa River
through Dinosaur National Monument. The trip was very eye opening for me and I would like to do more
work, and possibly research, in the fight against invasive species such as Tamarisk and Russian Olive in the
Colorado River Basin. After I graduate I plan on joining Engineers Without Borders and traveling around
South America to help create better access to safe drinking water and improve sanitation. When I was a
sophomore at the Lowell Whiteman School I traveled with the school to Bolivia for my foreign trip. As a
service project my group installed a water filter, utilizing rocks, gravel, sand, clay, and silt, to provide safe
drinking water to a small village close to Rurrenbaque, Bolivia, in the Amazon Basin. It was an amazing
experience to help these less-fortunate people by providing safe drinking water, and I feel I have an obligation
to participate in similar projects in the future, hopefully on a larger scale. I have learned that water-related
problems are often times very complex and do not have a simple solution, but require collaboration between
many groups and industries. While I am not sure of the exact direction that my career will take, I am very
excited about having a career in the water industry.”

Awards and Achievements

2

Publications from Prior Years
1. 2005CO117B ("Occurrence and Fate of Organic Wastewater Contaminants in Onsite Wastewater
Systems and Implications for Water Quality Management") - Water Resources Research Institute
Reports - Borch, Thomas, Yun-Ya Yang, James L. Gray, Edward T. Furlong, Jessica G. Davis,
Rhiannon C. ReVello. 2012, Steroid Hormone Runoff from Agricultural Test Plots Applied with
Municipal Biosolids, Colorado Water Institute, Colorado State University, Fort Collins, CO. 9 pages.

Publications from Prior Years

1