RECLAMATION 


Managing Water in the West 


Colorado River Basin 

Water Supply and Demand Study 

Technical Report F-Development of Options and Strategies 

U.S. Department of the Interior 

Bureau of Reclamation December 2012 
Mission Statements

The U.S. Department of the Interior protects America’s natural 

resources and heritage, honors our cultures and tribal communities, 

and supplies the energy to power our future. 

The mission of the Bureau of Reclamation is to manage, develop, 

and protect water and related resources in an environmentally and 

economically sound manner in the interest of the American public.
U.S. Department of the Interior

Bureau of Reclamation December 2012

Colorado River Basin 

Water Supply and Demand Study

Technical Report F — 

Development of Options 

and Strategies

December 2012 F-iii

Contents

Page

1.0 Introduction .............................................................................................................. F-1

2.0 Approach for Options and Strategies Development ............................................. F-2

3.0 Summary of Options Received ............................................................................... F-3

4.0 Characterization of Options.................................................................................... F-5

4.1 Approach for Characterization ....................................................................... F-5

4.2 Characterization Criteria and Assumptions ................................................... F-5

4.3 Limitations of Characterization Process ........................................................ F-8

5.0 Option Characterization Results ............................................................................ F-9

5.1 Importation ..................................................................................................... F-9

5.3 Reuse .............................................................................................................. F-19

5.4 Local Supply .................................................................................................. F-23

5.5 Watershed Management................................................................................. F-26

5.6 Municipal and Industrial Water Conservation ............................................... F-33

5.7 Agricultural Water Conservation ................................................................... F-39

5.8 Energy Sector Water Use Efficiency ............................................................. F-48

5.9 System Operations ......................................................................................... F-50

5.10 Water Transfers, Exchanges, and Banking .................................................... F-57

5.11 Water Management and Allocation ............................................................... F-61

5.12 Tribal Water ................................................................................................... F-63

5.13 Data and Information ..................................................................................... F-65

5.14 Characterization Summary ............................................................................. F-67

6.0 Development of Portfolios ....................................................................................... F-68

6.1 Defining Portfolios and Option Preferences .................................................. F-72

6.2 Portfolio A ..................................................................................................... F-73

6.3 Portfolio B ...................................................................................................... F-76

6.4 Portfolio C ...................................................................................................... F-79

6.5 Portfolio D ..................................................................................................... F-81

6.6 Portfolio Comparison ..................................................................................... F-83

6.7 Implementing Dynamic Portfolios in CRSS .................................................. F-85

7.0 Summary and Limitations ...................................................................................... F-86

8.0 References ................................................................................................................. F-87

Disclaimer ............................................................................................................................. F-89

Tables

Page

F-1 Criteria Used to Characterize Representative Options .............................................. F-6

F-2 Study Area M&I Conservation Assumptions ............................................................ F-36

F-3 Reductions in Colorado River Basin Demand (afy) for Each Demand Scenario 

and Conservation Level at 2060 ................................................................................ F-37
Colorado River Basin

Water Supply and Demand Study

F-iv December 2012

Tables (continued)

Page

F-4 Estimated Costs per af Demand Reduction for Each Conservation 

Level at 2060.............................................................................................................. F-38

F-5 Estimated Potential Water Savings Percentages at the Farm Scale for 

Each Agricultural Water Conservation Measure ....................................................... F-43

F-6 Estimated Potential Water Savings at the Farm Scale for Each 

Agricultural Water Conservation Measure ................................................................ F-44

F-7 Agricultural Conservation Annual Costs per af of Savings by 

Implementation Type ................................................................................................. F-45

F-8 Summary of Option Cost and Potential Yields by 2035 and 2060 ............................ F-68

F-9 Option Criteria and Categories Utilized in the Development of Portfolios ............... F-72

F-10 Option Criteria Preferences for the Four Portfolios ................................................... F-73

F-11 Summary of Included Options for Portfolio A .......................................................... F-75

F-12 Summary of Included Options for Portfolio B .......................................................... F-78

F-13 Summary of Included Options for Portfolio C .......................................................... F-80

F-14 Summary of Included Options for Portfolio D .......................................................... F-82

F-15 Frequency of Option Inclusion Across the Four Study Portfolios ............................. F-84

Figures

F-1 Overall Study Approach ............................................................................................ F-2

F-2 Distribution of Options Received .............................................................................. F-4

F-3 Summary Characterization for Importation Options ................................................. F-15

F-4 Summary of Characterization Ratings for Desalination Options .............................. F-20

F-5 Summary of Characterization Ratings for Reuse Options ......................................... F-24

F-6 Summary of Characterization Ratings for Local Supply Options ............................. F-27

F-7 Summary of Characterization Ratings for Watershed Management Options ............ F-34

F-8 Summary of Characterization Ratings for M&I Conservation Options .................... F-40

F-9 Summary of Characterization Ratings for Agricultural Water Conservation 

Options ....................................................................................................................... F-47

F-10 Summary of Characterization Ratings for Energy Water Use Efficiency Options ... F-51

F-11 Summary of Characterization Ratings for System Operations Options .................... F-56

F-12 Summary of Options Characterization Ratings (aggregated by option groups) ........ F-70
Technical Report F — Development

of Options and Strategies

December 2012 F-v 

Figures (continued)

Page

F-13 Relationships between Options in the Four Study Portfolios .................................... F-71

F-14 Ordered Options, Yield, Cost, and Timing Availability for Portfolio A ................... F-74

F-15 Total Portfolio Yield over Time by Average Cost for Portfolio A ............................ F-76

F-16 Ordered Options, Yield, Cost, and Time Availability for Portfolio B ....................... F-77

F-17 Total Portfolio/ Yield over Time by Average Cost for Portfolio B ........................... F-79

F-18 Ordered Options, Yield, Cost, and Time Availability for Portfolio C ...................... F-80

F-19 Total Portfolio Yield over Time by Average Cost for Portfolio C ............................ F-81

F-20 Ordered Options, Yield, Cost, and Timing Availability for Portfolio D ................... F-82

F-21 Total Portfolio Yield over Time by Average Cost for Portfolio D ............................ F-83

F-22 Total Yields over Time for Average Costs less than or equal to $750 per af, 

$1,000 per af, and $1,250 per af for Portfolios .......................................................... F-86

Appendices

F1 Options and Strategies Sub-Team Members

F2 Summary of Options Received 

F3 Options Characterization Criteria and Rating Descriptions

F4 Option Characterization – Importation 

F5 Option Characterization – Desalination

F6 Option Characterization – Reuse 

F7 Option Characterization – Local Supply 

F8 Option Characterization – Watershed Management 

F9 Option Characterization – Municipal & Industrial Water Conservation 

F10 Option Characterization – Agricultural Water Conservation 

F11 Option Characterization – Energy Water Use Efficiency

F12 Option Characterization – System Operations

F13 Options Submitted by the Ten Tribes Partnership and the Inter Tribal Council of Arizona 

December 2012 F-vii

Acronyms and Abbreviations 

2007 Interim Guidelines Record of Decision for Colorado River Interim Guidelines for Lower 

Basin Shortages and the Coordinated Operations for Lake Powell and 

Lake Mead 

af acre-feet

afy acre-feet per year

Basin Colorado River Basin 

Basin States Colorado River Basin States 

BLM Bureau of Land Management 

BMP best management practice

CALFED California Water Policy Council and Federal Ecosystem Directorate

CAP Central Arizona Project

CBM coal bed methane

CCP Central Colorado Project

CII commercial, institutional, and industrial 

Compact Colorado River Compact of 1922 

CRSS Colorado River Simulation System 

CUWCC California Urban Water Conservation Council 

desal desalination

DOI U.S. Department of the Interior 

EPA U.S. Environmental Protection Agency 

EIS Environmental Impact Statement

gpcd gallons per capita per day

ICS Intentionally Created Surplus 

IID Imperial Irrigation District

ITCA Inter Tribal Council of Arizona 

kafy thousand acre-feet per year

KBRT Klamath Basin Rangeland Trust

kWh kilowatt hours 

mafy million acre-feet per year

Mexico United Mexican States 

MW megawatts

MWD Metropolitan Water District of Southern California

M&I municipal and industrial 
Colorado River Basin

Water Supply and Demand Study

F-viii December 2012

O&M operation and maintenance 

OM&R operation, maintenance, and replacement 

QSA Quantification Settlement Agreement

Reclamation Bureau of Reclamation

ResOps reservoir operations 

SoCal Southern California 

Study Colorado River Basin Water Supply and Demand Study 

SysOps system operations

TDS total dissolved solids

tribes federally recognized tribes

USGS U.S. Geological Survey 

WaterSMART Sustain and Manage America's Resources for Tomorrow

weather mod weather modification 
December 2012 F-1 

Technical Report F — Development of 

Options and Strategies

1.0 Introduction

The Colorado River Basin Water Supply and Demand Study (Study), initiated in January 2010, 

was conducted by the Bureau of Reclamation’s (Reclamation) Upper Colorado and Lower 

Colorado regions, and agencies representing the seven Colorado River Basin States (Basin 

States) in collaboration with stakeholders throughout the Colorado River Basin (Basin). The 

purpose of the Study is to define current and future imbalances in water supply and demand in 

the Basin and the adjacent areas of the Basin States that receive Colorado River water over the 

next 50 years (through 2060), and to develop and analyze adaptation and mitigation strategies to 

resolve those imbalances. The Study contains four major phases to accomplish this goal: Water 

Supply Assessment, Water Demand Assessment, System Reliability Analysis, and Development 

and Evaluation of Options and Strategies for Balancing Supply and Demand.

Spanning parts of the seven states of Arizona, California, Colorado, New Mexico, Nevada, Utah, 

and Wyoming, the Colorado River is one of the most critical sources of water in the western 

United States. The Colorado River is also a vital resource to the United Mexican States 

(Mexico). It is widely known that the Colorado River, based on the inflows observed over the 

last century, is over-allocated, and supply and demand imbalances are likely to occur in the 

future. Up to this point, this imbalance has been managed, and demands have largely been met as 

a result of the considerable amount of reservoir storage capacity in the system, the fact that the 

Upper Basin States are still developing into their apportionments, and efforts the Basin States 

have made to reduce their demand for Colorado River water. 

Concerns regarding the reliability of the Colorado River system to meet future needs are even 

more apparent today. The Basin States include some of the fastest-growing urban and industrial 

areas in the United States. At the same time, the effects of climate change and variability on the 

Basin water supply has been the focus of many scientific studies that project a decline in the 

future yield of the Colorado River. Increasing demand, coupled with decreasing supplies, will 

certainly exacerbate imbalances throughout the Basin. 

It is against this backdrop that the Study was conducted to establish a common technical 

foundation from which important discussions can begin regarding possible strategies to reduce 

future supply and demand imbalances. The content of this report is a key component of that 

technical foundation and describes the Study’s development of options and strategies. 

This development was initiated in November 2011 when project participants, stakeholders, and 

the public were encouraged to submit options and strategies to help resolve future supply and 

demand imbalances in the Study Area. Through February 2012, 160 ideas were submitted. The

Study does not result in the selection or funding of a particular proposed option or set of options. 

Rather, the Study is intended to explore a broad range of options to help address future 

imbalances and the performance of those options across a range of future conditions. The Study 

also lays the foundation for future development and implementation of a number of options 

identified.
Colorado River Basin

Water Supply and Demand Study

F-2 December 2012

This report describes the submitted options, the process for characterization of these options, the 

results of characterization, and the development of exploratory portfolios from the 

characterization results to address future supply and demand imbalances. 

2.0 Approach for Options and Strategies Development

The overall Study approach and associated technical reports are shown in figure F-1. As outlined 

in Technical Report E - Approach to Develop and Evaluate Options and Strategies, the Study 

objectives center on addressing two primary questions: 

1. What is the future reliability of the Colorado River system to meet the needs of Basin 

resources through 2060? 

2. What are the options and strategies that can mitigate future risks to these resources?

The second question is the focus of this report. This question examines the potential water 

management response to future imbalances in supply and demand. The process to examine this 

response is shown in figure F-1 as the shaded boxes representing the identification and 

characterization of individual options and the subsequent development of portfolios of options. 

The effectiveness of the options and strategies at resolving imbalances and improving the 

reliability of the Colorado River system is described in Technical Report G – System Reliability 

Analysis and Evaluation of Options and Strategies.

FIGURE F-1 

Overall Study Approach

Framing of the Study

Development of Water 

Supply Scenarios

Development of Water 

Demand Scenarios

Identification of System 

Reliability Metrics

Identification and 

Characterization of Options

Development of Portfolios of 

Options

Evaluation of System Reliability without 

Options and Strategies

Characterization of System 

Vulnerabilities

Evaluation of System Reliability with 

Options and Strategies

Summary of Findings and 

Future Considerations

Plan of Study

Technical Report A

Technical 

Report F

Technical Report B

Study Report

Technical Report C Technical Report D

Technical Report E 

Technical 

Report G
Technical Report F — Development

of Options and Strategies

December 2012 F-3 

The following paragraphs provide a high-level summary of the development and characterization 

process as well as the development of portfolios. Additional detail is presented in the sections 

that follow.

An Options and Strategies Sub-Team, composed of representatives from Reclamation, the Basin 

States, federally recognized tribes (tribes) and communities, and conservation organizations, was 

established to develop options and strategies. Sub-Team members are listed in appendix F1 of 

this report. 

The general approach for the development of options and strategies is summarized as follows:

• Solicit input – In order to examine a broad range of potential options, Study participants, 

interested stakeholders and the general public were asked to submit options. 

• Organize options – The options were reviewed and organized into four broad types: 

(1) increase water supply, (2) reduce water demand, (3) modify operations, or (4) governance 

and/or implementation1. Options were further assigned individual categories based on their 

primary function such as importation, desalination, and municipal and industrial (M&I) 

conservation. 

• Characterize options – Each option was characterized using a set of 17 criteria, including 

both quantitative criteria such as timing of implementation, annualized cost per acre-foot (af), 

yield, and energy use, and qualitative criteria such as technical feasibility and implementation 

risk. 

• Develop representative options – In order to avoid redundancy and simplify analysis, 

representative options were developed from the pool of submitted options. 

• Develop portfolios – No single option, or type of project, will likely be adequate to meet all 

of the future demands of the Basin resources. Rather, a combination of options (portfolio) 

will be needed to address the imbalances between supply and demand. As such, portfolios 

representing potential strategies to address future supply and demand imbalances were 

developed from the representative options and option characterization results. Portfolios were 

developed by selecting certain option characteristics based on the particular strategy 

(e.g., remove options that rated low for implementation risk or technical feasibility). 

Each portfolio described in this report was then simulated across all water supply and demand 

scenarios to assess the ability of the strategy to address imbalances between supply and demand 

and resolve individual vulnerabilities. The results of these simulations are described in Technical 

Report G – System Reliability Analysis and Evaluation of Options and Strategies. 

3.0 Summary of Options Received 

A report, Phase 4: Development and Evaluation of Opportunities for Balancing 

Water Supply and Demand – Request for Ideas (Reclamation, 2011), was published to 

provide relevant information to those interested in submitting options and strategies. The 

report provided preliminary projections of future supply and demand imbalances, a 

summary of previous studies that assessed future imbalances and explored options 

 

1 Implementation refers to a mechanism that could be used to facilitate options rather than a specific option (for example, a tax used to raise 

funds for developing projects or monitoring).
Colorado River Basin

Water Supply and Demand Study

F-4 December 2012

and strategies, a description of ongoing efforts for balancing supply and demand, and 

presented a summary of the Study work in progress. 

A total of 160 options were received. The submittals are summarized in appendix F2 and the 

original submittals are available via links from the electronic version of appendix F2 available on 

the compact disc that accompanies this report and the version of appendix F2 on the Study 

website at http://www.usbr.gov/lc/region/programs/crbstudy.html. The options were separated 

into four types based on their approach for resolving the imbalance: 

• Increase Supply: These options include suggestions for importing water into the Basin from 

the Green River, Snake River, from Alaska or the Columbia River via ocean routes, or 

exchanges with Missouri and Mississippi river supplies; desalination projects along the 

Pacific Ocean, along the Gulf of California (Gulf), or brackish water desalting projects in 

California and Arizona; wastewater reuse; greater use of local supplies; and application of 

watershed management techniques such as weather modification or vegetation management

to increase supply. 

• Reduce Demand: These options include suggestions for M&I water conservation, agricultural 

water conservation, and energy water use efficiency.

• Modify Operations: This type includes suggestions for methods for reducing evaporation

from lakes and canals, changing system operations, augmenting storage, and inclusion of 

water banking and transfer programs. 

• Governance and Implementation: These suggestions are related to changes in policy, 

management, legal structure, or future implementation and governance of the Colorado River 

system. 

A total of 55 options were submitted related to increasing supply, 42 options related to reducing 

demand, 22 options related to modifying operations, and 41 options related to governance and 

implementation. The percentage of options represented by each category is shown on figure F-2. 

The options were further organized into categories and groups, from which representative 

options were selected or developed for consideration in the analysis. 

FIGURE F-2 

Distribution of Options Received

34%

26%

14%

26%

Increase Supply

Reduce Demand

Modify Operations

Governance and 

Implementation
Technical Report F — Development

of Options and Strategies

December 2012 F-5 

4.0 Characterization of Options

The Plan of Study (see Study Report, Appendix 1 – Plan of Study) identified specific objectives 

related to the development and evaluation of options. As the Study progressed, a definitive 

process for the characterization of options was developed. This process included the quantitative 

characterization of options through the assignment of ratings to a number of evaluation criteria. 

Additionally, this process included the qualitative characterization of options that do not directly 

increase supply or reduce demand. The qualitative characterization consisted of identification of 

opportunities and constraints, including potential legal and regulatory issues. 

4.1 Approach for Characterization 

Option characterization was performed in order to describe each of the submitted options, 

provide a relative comparison of the option attributes, and support the eventual development of 

option and portfolio evaluations. Characterization of proposed options was primarily based on 

information provided by the option submitter; however, available literature and/or relevant 

studies were reviewed to support the characterization process. 

Characterization of the options was based on 17 evaluation criteria that are consistent with the 

criteria outlined in the Plan of Study. The approach to characterization included the following 

steps to each of the 17 criteria for each of the proposed options: 

1. Review the submission of the option for relevance and completeness of data. In some cases, 

clarification or additional information was requested from the submitter as appropriate and if 

needed for appropriate characterization of the option. Options that have limited definition or 

are not directly amenable to characterization through the 17 evaluation criteria were 

identified and cataloged for future consideration but are not characterized here.

2. Validate and refine information submitted with the option. Criteria information submitted 

with the option was compared with similar information in relevant case studies or readily 

available databases to confirm accuracy. If quantitative information was not readily available 

for a criterion, the Options and Strategies Sub-Team used its collective expertise and 

experience to qualitatively evaluate information submitted. 

3. Characterize each option using a classification system. For the appropriate options, ratings 

were generated for each criterion using the submitted or refined information. Ratings were 

reviewed by the Options and Strategies Sub-Team. A characterization summary table was 

developed by listing each rating for an option. Where possible quantitative information was 

developed (e.g., cost, yield, and timing). In addition, for each option a rating of A, B, C, D, 

or E was also assigned for each criterion. In general, the “A” rating is most favorable and the 

“E” rating is least favorable. If insufficient information was available to assign a rating, the 

associated entry in the option characterization summary table was left blank. 

4.2 Characterization Criteria and Assumptions 

Option characterization was based on the 17 criteria shown in table F-1. A summary description 

of the criteria is provided in the table. A more complete discussion of the criteria and ratings 

descriptions is provided in appendix F3. Attachment A of appendix F3 contains more detailed 

descriptions of the ratings. Attachment B provides the methods used for completing the unit cost 

calculations. Attachment C presents the detailed characterization information and is available on 
Colorado River Basin

Water Supply and Demand Study

F-6 December 2012

the compact disc that accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

TABLE F-1 

Criteria Used to Characterize Representative Options

Criteria Summary Description of Criteria

Quantity of Yield The estimated long-term quantity of water generated by the option—either an 

increase in supply or a reduction in demand

Timing Estimated first year that the option could begin operation

Technical Feasibility Technical feasibility of the option based on the extent of the underlying 

technology or practices

Cost The annualized capital, operating, and replacement cost per af of option yield

Permitting Level of anticipated permitting requirements and precedent of success for 

similar projects

Legal Consistency with current legal frameworks and laws, or precedent with 

success in legal challenges

Policy Considerations Extent of potential changes to existing federal, state, or local policies that 

concern water, water use, or land management

Implementation Risk Risk of achieving implementation and operation of option based on factors 

such as funding mechanisms, competing demands for critical resources, 

challenging operations, or challenging mitigation requirements

Long-term Viability Anticipated reliability of the option to meet the proposed objectives over the 

long term

Operational Flexibility Flexibility of option to be idled from year to year with limited financial or other 

impacts

Energy Needs Energy required to permit full operation of the option, including treatment, 

conveyance, and distribution

Energy Source Anticipated energy source to be used to allow option to be operational

Hydropower Anticipated increases or decreases in hydroelectric energy generation 

associated with implementation of the option

Water Quality Anticipated improvements or degradation in water quality associated with 

implementation of the option

Recreation Potential impacts to recreational activities including in-river and shoreline 

activities

Other Environmental Factors Other environmental considerations, such as impacts to air quality, or 

aquatic, wetland, riparian, or terrestrial habitats

Socioeconomics Potential impacts to socioeconomic conditions in regions within or outside of 

the Basin as a result of implementing the option
Technical Report F — Development

of Options and Strategies

December 2012 F-7 

When performing the characterization, the following overarching assumptions were made: 

• Level of Evaluation - Consistent with the scope of the Study, the options were evaluated at a 

screening level of analysis only. In some cases, very detailed information on the options was 

provided, but in most cases the options were only conceptually described in the original 

submissions. Additional research was performed to validate and refine the submitted 

information, but this was of a limited nature and at an appraisal level. 

• Basin-wide Approach - Where possible, options were conceptualized as distributed, Basinwide options (e.g., conservation and reuse) as opposed to options implemented by specific 

entities in specific geographies. Several options, however, are geographically distinct (e.g., 

specific import options) and were retained in this form. 

• Cost of Options - All costs presented were developed based on annualized capital costs 

added to annual operation and maintenance (O&M) costs (power, chemicals, etc.). Costs for 

infrastructure-related options were derived from industry-based parametric cost estimates 

that are commonly applied for water infrastructure projects. These costs include adjustments 

for proposed location and the scale of the project. Annualization of capital costs was 

performed using federal guidelines (see attachment B to appendix F3). 

• Stepped Implementation of Large Options - Several options are sufficiently large that the 

potential exists to implement only a portion of the total option. In general, any option that 

may have more than 200 thousand acre-feet per year (kafy) of yield was separated into steps 

of up to 200 kafy. This scaling or phasing of large options allowed for characterization to 

reflect increasing complexity as project size increases. 

• Independent Characterization of Options - Although it is likely that several options will be 

combined as part of eventual portfolios, the option characterization considered each option 

independently. 

• Option “Fence Line” - The characterization of the options was limited to the direct effect of 

the action within the boundary, or fence line, of the option itself. For example, conversion of 

water-cooled power plants to air cooling results in a reduction in water demand. However, 

this conversion also results in a reduction of net power generation. Although this could be 

mitigated through energy conservation or energy development elsewhere, the option was 

evaluated independently of actions that may be taken outside of the “fence line.” 

• Sense of Urgency - The success rate and timeframe for which similar past projects have been 

implemented has varied widely. This variation is due to resistance from opponents, urgency 

from proponents, and political support or opposition. When evaluating permitting and 

potential timing of completion, it was assumed that there would be wide recognition of the 

associated issues, and therefore significant political alignment, sense of urgency, and 

consistent pursuit throughout the feasibility, environmental review, permitting, and 

implementation stages. The scope, scale, and timing of potential imbalances suggest the need 

for timely action coordinated among the stakeholders. This coordinated action is an 

important consideration in rating, in particular, the timing of option availability. 
Colorado River Basin

Water Supply and Demand Study

F-8 December 2012

4.3 Limitations of Characterization Process 

The process undertaken to characterize options strived to develop an objective and consistent 

evaluation of the options. Several iterations of the option characterization were performed in an 

attempt to normalize ratings wherever possible. However, several limitations are inherently 

associated with the characterization of such a broad range of options. The limitations of the 

characterization process are as follows: 

• Limited Level of Analysis. The intent of the characterization was to perform a high-level 

analysis of a broad range of options potentially available to resolve Basin imbalances. Study 

resources limited performing highly detailed evaluations. Limiting the level of analysis 

helped ensure that all options were considered at a high level, but also added uncertainty to 

the characterization results because all of the potential challenges associated with option 

development and implementation may not have been considered. Further, the 

characterization did not specifically consider future financing and/or economic impacts. 

• Some options considered have detailed information available from similar developed projects 

and other studies, whereas other options, specifically those associated with agricultural and 

M&I conservation and reuse, require an understanding of development policies, regulatory 

constraints, legal implications, and water planning criteria that vary significantly throughout 

the Study Area. A detailed assessment by individual location for those options was beyond 

the scope of the Study. Instead, the Study provides an appraisal-level approach to 

characterizing these options, and then applies these assumptions Basin-wide. The 

assumptions were adopted for purposes of the Study and do not necessarily reflect 

achievable, or even desirable, local conservation goals for individual municipalities or 

agricultural locations.

• Potential for Subjectivity. The classification system used in the characterization process was 

relatively prescriptive; however, there was still some room for subjectivity when selecting 

the appropriate ratings for each evaluated option. There was also some potential subjectivity 

related to defining the “fence line” of each option. However, the overall methodology applied 

for the option characterization underwent peer review as one means to validate its 

approach. The review was favorable toward the approach taken in the Study, but 

acknowledged the potential for differences in viewpoints for particular criteria Still, not all 

members of the Options and Strategies Sub-Team were in agreement with all ratings, but 

they recognize that future efforts will result in a more in-depth assessment of the criteria. 

• Uncertainty. The characterization was performed based on limited and high-level analyses. 

Therefore, knowledge of items such as costs, permit requirements, and long-term feasibility 

are still highly uncertain. For example, cost estimates for infrastructure-type projects are 

based on similar past projects with adjustments for parameters such as scale and location. 

These adjustments are approximate, especially for projects where the scale of the project is 

larger than any previously completed similar project. Cost estimates for non-structural type 

projects are often even more uncertain because historical documentation of costs for similar 

past projects are often not fully applicable or fully documented, or such projects are based on 

changes in human behavior. In regards to infrastructure-type options, past studies by the 

Association for the Advancement of Cost Engineering show that concept- level estimates can 

typically have an expected accuracy of between -30 to 50 percent. However, it is important to 

note that many of the infrastructure options and most non-infrastructure options have 
Technical Report F — Development

of Options and Strategies

December 2012 F-9 

sufficient uncertainty in cost assumptions that an even wider range of cost variation is 

possible. Despite the uncertainties in estimating the magnitude of costs, a significant effort 

was made to provide cost estimates that are useful when considering relative costs. Similar 

statements can be made related to uncertainty when characterizing options against many 

other criteria. The characterization process for the non-cost items have some degree of 

uncertainty, but it is still useful for providing understanding of the potential advantages and 

disadvantages of the different options, considering a diverse set of criteria.

5.0 Option Characterization Results 

The following sections present the characterization results for each of the representative options 

developed from the major option category. These option categories are: Importation, 

Desalination, Reuse, Local Supply, Watershed Management, M&I Conservation, Agricultural 

Water Conservation, Energy Water Use Efficiency, System Operations, and Water Transfers, 

Exchanges, and Banking. The presentation begins with a summary of the submitted options, 

followed by a description of each representative option in the category. These descriptions are 

followed by the characterization results, summarized by quantity of yield, timing, cost, and other 

key considerations.

5.1 Importation 

River and other out-of-Basin freshwater imports have been proposed to increase the overall 

water supply of the Basin. Fourteen options related to river or other freshwater imports were 

received. The submitted options were reviewed and organized into three groups according to the 

location at which the imported water would provide water to the Colorado River or tributary or 

would provide exchange water for regions reliant upon Colorado River supplies. Representative 

options were developed for each option group to represent the distinct nature of the options 

within each group. When potential yield of a representative option exceeds 200 kafy and the 

option is scalable, the representative option was characterized in progressive 200 kafy “steps” to 

represent likely project phasing. The option groups and representative options are described 

below. 

Additional detail related to the representative options and specific characterization is included 

in appendix F4. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

5.1.1 Imports to the Colorado Front Range 

This group of options includes importing water from the Missouri River or Mississippi River to 

areas adjacent to the Basin that could use this water to meet projected shortfalls and/or reduce the 

amount of water these areas divert from the Basin. All of the Import to Front Range options 

involve large-scale diversion facilities (intake and diversion facilities of at least 800 cubic feet 

per second), more than 700 miles of conveyance infrastructure spanning at least two states, and 

more than 700 megawatts (MW) of power for pumping. Water would be conveyed to the Front 

Range of Colorado and specific areas of New Mexico and integrated into existing water supply 

systems. Although these options are termed “imports,” water would not actually be imported into 
Colorado River Basin

Water Supply and Demand Study

F-10 December 2012

the Basin. Rather, water would be delivered to these adjacent areas to reduce the amount of water 

exported by transbasin diversion (or the amount that could be exported in the future) from the 

upper Colorado and San Juan rivers. In order for this option to become viable, support from the 

State of Colorado would be required. 

Two representative options were developed from this group of options to reflect the differences 

in potential location of diversion, conveyance infrastructure needs, and associated impacts. The 

representative options consist of the following: 

• Missouri River Imports 

• Mississippi River Imports 

5.1.2 Imports to the Green River Headwaters 

This group of options includes diverting water from the upper headwaters of rivers adjacent to 

the Green River to the headwaters of the Green River. Potential sources of supply are diversions 

from the Bear River, upper Snake River2, or Yellowstone River. These potential projects involve 

intake and diversion facilities, pumping plants and conveyance facilities, and delivery to the 

Green River. Because these options are focused on headwaters-to-headwaters transbasin 

diversions, the size of the projects (in terms of magnitude of water and facilities required) are 

smaller in scale than other importation options. 

Three representative options were developed from this group of options to reflect the differences 

in potential location of diversion, conveyance infrastructure needs, and associated impacts. The 

representative options consist of the following: 

• Bear River Imports 

• Snake River Imports 

• Yellowstone River Imports 

5.1.3 Imports to Southern California 

This group of options is focused on importing high-quality water from other regions using ocean 

routes to Southern California coastal areas. Potential sources of water include the Columbia 

River2

, rivers in Alaska, or icebergs. Delivery mechanisms include sub-ocean pipelines for 

Columbia River supplies, tanker ships for Alaskan river supplies, or tug boats for icebergs. All of 

the options in this group require extensive transport or conveyance of water from the source 

regions to Southern California and require relatively complex facilities and operations to 

integrate the supply within the current water supply system in Southern California. 

Four representative options were developed from this group of options to reflect the differences 

in potential location of imported water, modes of transport and conveyance, and associated 

impacts. The representative options consist of the following: 

• Columbia River Imports 

• Icebergs

 

2 Among the more than 150 options submitted to Reclamation as responsive to the Plan of Study, additional importation of water supplies from 

various sources, including importation of water from the Snake and Columbia River systems, were submitted to the Study. Such options were 

appropriately reflected in the Study but did not undergo additional analysis as part of a regional or river basin plan or any plan for a specific 

Federal water resource project. This Study is not a regional or river basin plan or proposal or plan for any Federal water resource project.
Technical Report F — Development

of Options and Strategies

December 2012 F-11

• Tankers

• Water Bags

The options related to Tankers and Water Bags were separated into sub-options of 200-kafy steps

to allow for incremental characterization of these options. 

5.1.4 Characterization of Options 

Quantity of Yield

The total potential yield of all importation options considered in the Study is more than 3 million 

acre-feet per year (mafy). However, because the largest options are limited by the ability to 

convey, integrate, and exchange import water within existing water supply systems in Southern 

California, the Front Range of Colorado, and the Rio Grande in New Mexico, many of the 

options are mutually exclusive (e.g., either Mississippi River imports or Missouri River imports, 

not both). Considering these limitations, the potential yield of the options is more likely in the 

range of 1.2 to 1.3 mafy. The potential yield was assessed independently from technical 

feasibility, reliability, and other criteria. The characterization of these other criteria is 

summarized in subsequent sections. 

The potential quantity of yield from Imports to the Front Range was limited by the realistic 

hydraulic capacity of a single large-diameter pipeline and integration potential within the 

existing Front Range water system. Specifically, limiting the pipe size to 144 inches and 

maintaining flow rates so that friction loss is less than 1 foot per 1,000 feet of pipe length results 

in a yield of about 600,000 acre-feet per year (afy). Similarly, the ability to exchange import 

water for reduced future diversions from the Colorado River to the Front Range limited 

consideration of larger quantities. Because the available diversion from the Missouri and 

Mississippi Rivers is not envisioned to be supply-limited to 600,000 afy, multiple parallel pipes 

could increase the quantity of yield of this option, but it is likely that service areas would need to 

be expanded beyond the Front Range and the Rio Grande to exchange for significantly reduced 

Colorado River diversions. 

Conversely, the potential yield from the Import to Green River Headwaters options were limited 

by estimates of the potentially available supply. Previous analyses prepared as part of the 2008 

Colorado River Augmentation Study (Colorado River Water Consultants, 2008) estimated 

maximum limits to the diversion potential from the Snake, Bear, and Yellowstone Rivers and 

were used in this assessment. The previous study included evaluation of both water rights and 

hydraulic assessments to estimate potential diversion from the adjacent headwaters. The 

projected yield for these import options ranges from 33,000 afy to 75,000 afy. 

The estimates of potential yield from Imports to Southern California were limited by the ability 

to integrate the import supply into the existing water supply system within Southern California. 

The availability of supply for locations in Alaska or the Columbia River was not assumed to be 

the limiting factor. Integrating large quantities of new supply to offset Colorado River diversions 

would be difficult due to infrastructure constraints. Although the exact integration limit is 

difficult to quantify, 600,000 afy was selected based on rough estimates of integration capability.

This volume is coincidentally consistent with other large-scale import options and therefore 

provides some degree of comparability.
Colorado River Basin

Water Supply and Demand Study

F-12 December 2012

Timing

The Import to Front Range group of options consists of large-scale infrastructure projects with at 

least 700 miles of conveyance infrastructure crossing at least two states and requiring at least 

700 MW of power for pumping. Conveyance projects of this scale are rare and would require 

extensive feasibility studies, permitting, and design. Although the scale adds complexity, the 

type of infrastructure required has been implemented in many historical projects and has proven 

to be highly reliable. Confirming technical feasibility is anticipated to take approximately 

5 years. The permitting phase will require multi-state negotiations, possible permits for new 

power plants, National Environmental Policy Act compliance, and evaluation of Endangered 

Species Act impacts. Even if the permit process were pursued with urgency and with political 

support, the process is expected to take up to 15 years. Once permitted, numerous design and 

construction crews could be mobilized to simultaneously construct several segments of the 

project. It is therefore possible to construct large-scale water transmission projects of this size in 

approximately 10 years. The total estimated time before the option could become operational is 

30 years. 

The group of options related to Imports to the Green River Headwaters is anticipated to divert 

quantities of less than 75,000 afy. The conveyance facilities vary in length between 15 miles and 

140 miles and the infrastructure used to convey the water has been proven reliable. Therefore, 

project feasibility could potentially be evaluated within 3 years. Although these projects are not 

major infrastructure projects, the concepts include transbasin diversions from areas designated as 

state or national forests; therefore, special use permits for construction in the public lands will be 

required. Also, transbasin water projects have become increasingly challenging to permit due to 

both political and environmental concerns. Due to these concerns, at least 7 years of permitting is 

anticipated. Once permitted, numerous design and construction crews could implement these 

types of projects in up to 5 years. The total estimated time before options within this group could 

become operational is 15 years. 

All options within the Imports to Southern California group of options could take at least 

10 years to evaluate feasibility. Interstate negotiations would be required, as well as permitting at 

both the source water location and receiving water locations. It is estimated that this permitting 

process could take between 5 and 10 years and could take longer for the sub-ocean pipeline due 

to potential additional marine-related permitting. Once permitted, it would likely take 5 years to 

design and construct the ports and procure the required ships for transfer by tankers, water bags, 

or icebergs. It would take longer to construct more than 1,000 miles of sub-ocean pipeline. In 

summary, the feasibility phase would require at least 10 years; permitting would require at least 

5 years; and implementation would require at least 5 years, totaling at least 15 years. The subocean pipeline is anticipated to require up to 40 years due to the uncertainty related to the 

feasibility of this option and longer time required for construction. 

Cost

To estimate costs for the Import to Front Range option group, topographic and aerial mapping 

were used to select a rough alignment for the proposed conveyance corridor. The pumping needs 

were estimated based on evaluating topographic relief and maintaining industry standard 

pressures. Once the size of the pipeline and number and size of the pumping stations were 

determined, recent historical parametric costs were used to estimate the total capital costs, which 

ranged from less than $9 billion to more than $14 billion for the different options. Annual costs 

include electricity costs, maintenance, repair, and replacement costs. The unit costs were 
Technical Report F — Development

of Options and Strategies

December 2012 F-13

developed by annualizing capital costs and adding in the associated annual O&M cost. The unit 

annual costs for the Import to Front Range options considered in the Study vary between 

$1,700 per af and $2,300 per af. 

The group of options that import water to the Green River was analyzed by assuming 

configurations that utilized existing reservoirs, minimized pipeline lengths and utilized tunnels to 

reduce energy costs where feasible. Once the size and length of the facilities were determined, 

cost database information was used to estimate the total capital costs. Annual costs include 

electricity costs, maintenance, repair, and replacement costs. The unit annual costs for the 

options considered in the Study vary between $700 per af and $1,900 per af. 

Costs for the Import to Southern California option group were based on literature research. 

Specifically, the cost per day to lease a Class VLCC (Very Large Crude Carrier) tanker ship 

(which includes the cost of the ship, crew, and fuel) was researched. The cost to construct a new 

terminal at an existing port near Los Angeles and in Alaska was estimated based on recent 

studies to build a new oil terminal in Los Angeles. The cost to build pipelines and pump stations 

from the port to Diamond Valley Lake was based on the cost of previously completed pipelines 

and pumping stations in this region. Total capital costs were estimated to be approximately 

$3.5 billion. The costs for sub-ocean pipeline concepts were based on previous Reclamation 

studies and were adjusted for inflation. The unit annual costs for the options considered in the 

Study vary between $2,700 per af and $3,400 per af

Other Key Considerations

In addition to yield, timing, and cost, the Front Range importations group of options were 

characterized against several other criteria. All of the Import to Front Range options were 

estimated to have very high energy needs and the potential for significant permitting, legal, and 

policy challenges due to project size, geographic extent, and concern related to potential impacts 

in the source watersheds. The resulting ratings for these criteria are low (“D” or “E”). The Front 

Range projects have high debt service costs because they are capital-intensive projects. 

Therefore, the Front Range options did not score well against operational flexibility criteria 

because the high cost of debt would still be incurred if the project is put into an idle mode. 

Although significant challenges would need to be overcome in order to implement such a 

project, once in operation the long-term viability (reliability of producing the expected yield) is 

expected to be relatively high. Imports to the Front Range would result in less water diverted 

than the State of Colorado is legally entitled to divert from the Colorado River headwaters, 

which would improve Basin hydropower, water quality, and recreation, and may improve some 

environmental conditions in the Basin; however, it is possible that the options would have some 

adverse impacts on the same criteria in the basin of origin due to reduced flows in those rivers. 

Imports to the Front Range would result in water quality that would meet all drinking water 

standards with conventional water treatment, but the source water quality would be poorer than 

the current supply used by many Front Range urban purveyors. Agreement from the State of 

Colorado, and the many water providers within Colorado, would have to occur in order for this 

option to be implemented. Moreover, to the extent that it would require reducing the amount of 

water that the State of Colorado is legally entitled to take from the Basin, this option could 

require an amendment to the Colorado River Compact of 1922 (Compact) and Upper Colorado 

River Basin Compact of 1948. 
Colorado River Basin

Water Supply and Demand Study

F-14 December 2012

In general, imports to the headwaters of the Green River are similar to those described for the 

Imports to the Front Range group of options, with the following exceptions. Implementation risk 

is assumed to be lower because the challenges associated with raising capital are assumed to be 

lower for these smaller projects. Long-term viability is assumed to be more uncertain because the 

diversions are greater in relative percentage to the natural flow than other options and could face

more long-term environmental challenges than diverting water from the Missouri or Mississippi 

rivers. The energy needs are much lower due to starting at higher elevations and the use of 

tunnels. Hydropower and recreation benefits are assumed to be fewer than the Front Range 

imports, due to the significantly lower flow volumes. Water quality impacts are assumed to be 

more positive because the water delivered to the Basin is essentially of the same quality as native 

Basin headwaters; however, water quality impacts in the basin of origin would also need to be 

considered. 

The Import to Southern California group of options rated relatively low for technical feasibility. 

This is because sub-ocean pipelines, iceberg towing at large scale, or tanker operation at this 

scale is largely unprecedented. Permitting, legal, and policy issues will have all of the same 

issues as the other imports and will also have issues related to California Coastal Commission 

permits and marine permits. As with Imports to the Front Range, implementation challenges for 

these options include raising significant capital. In addition, these options are more challenging 

to integrate into existing systems than the other importation options. All of the imports via ocean 

routes required extensive energy or fuel and therefore have long-term viability challenges. 

Impacts to hydropower, recreation, and the environment would depend on the resulting change in 

operations of the Colorado River and potentially could have negative impacts if the Import to 

Southern California water option is exchanged for Colorado River water for diversion by others. 

Bringing this high-quality water to the region is expected to have a positive impact to salinity 

levels in the receiving region. 

5.1.5 Characterization Summary

A summary of the characterization findings are shown in figure F-3. The top portion of the figure 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, some large options were broken into 200-kafy steps to reflect 

increasing complexity as project size increases. These steps are denoted numerically, with “step 

1” being the first 200-kafy step, followed by subsequent steps In general, a “C” rating is typically 

designated as mostly neutral (yellow); “A” is largely positive (green); and “E” is largely negative

(red). Refer to appendix F3 for specific criteria descriptions and rating scales. 
Technical Report F — Development

of Options and Strategies

December 2012 F-15

FIGURE F-3 

Summary Characterization for Importation Options

Southern California (SoCal)
Colorado River Basin

Water Supply and Demand Study

F-16 December 2012

Three representative options were developed from this group of options to reflect the different 

potential desalination plant locations. The representative options consist of the following: 

• Pacific Ocean Desalination in California

• Pacific Ocean Desalination in Mexico

• Gulf of California Desalination

The options related to Pacific Ocean desalination in California and Gulf of California 

desalination were separated into sub-options of 200-kafy steps to allow for incremental 

characterization of these large-scale options. 

5.1.6 Desalination of Agricultural Drainwater

This group of options includes constructing new diversions upstream of the Salton Sea on the 

New River and Alamo River that would capture agricultural drainage water and deliver it to a 

regional brackish water desalination facility. The desalinated water would be delivered back to 

the All American Canal upstream of the East Highline Canal, allowing the water to be delivered 

to Imperial Irrigation District (IID) by exchange to the and Coachella Valley Water District, 

which rely on the All American Canal system. Simultaneously, an in-kind amount of reduction in 

diversions is possible from the Colorado River at Imperial Dam by exchange. 

In this case, only one representative option was developed: 

• Salton Sea Drainwater Reuse

The Salton Sea Drainwater Reuse representative option was separated into sub-options of 

200-kafy steps to allow for incremental characterization of this large-scale options.

5.1.7 Desalination of Brackish Groundwater

This group of options is made up of relatively small local projects by municipal water providers 

in Southern California and Arizona consistent with past similar projects. This concept also 

includes refurbishing the Yuma Desalting Plant back to full-scale production.

Two representative options were developed from this group of options to reflect the differences 

in potential source water location, conveyance infrastructure needs, and associated impacts. The 

representative options consist of the following: 

• Southern California Groundwater Desalination 

• Brackish Water Desalting in the Yuma Area

5.1.8 Characterization of Options

Quantity of Yield

Based on discussions with MWD, yield from the options related to Pacific Ocean desalination in 

California are estimated to be limited to 600,000 afy. Yield from the options related to Pacific 

Ocean desalination near the border in Mexico is estimated to be limited to 75,000 afy. In the case 

of either Pacific Ocean representative option, integration considerations with existing 

infrastructure are the limiting factor. For the Gulf of California, additional yield is assumed to be 

limited to 1.2 mafy. However, for both Pacific Ocean and Gulf of California desalination 

options, sub-options of 200 kafy each were considered to allow for incremental characterization 

of these large-scale projects. 
Technical Report F — Development

of Options and Strategies

December 2012 F-17

Agricultural drainwater desalination is limited to the amount of agricultural drainage water 

entering the Salton Sea and limitations of maintaining sufficient supply to mitigate for 

environmental impacts (e.g., air quality of increased exposed playa) at the Salton Sea. Between 

300,000 afy and 500,000 afy of sustainable yield was assumed. Sub-options of up to 200 kafy

each were considered to allow for incremental characterization of this large-scale option. 

Yield from brackish groundwater desalination is limited by sustainable groundwater extraction 

rates, sustainable brine disposal capabilities, or the capacity of existing facilities. Without 

updating past studies, it is difficult to calculate the amount of remaining sustainable brackish 

groundwater yield in Southern California. A rough estimate based on those studies and 

previously identified projects is about 20,000 afy of additional sustainable yield remaining. The 

yield of brackish groundwater in the vicinity of Yuma, Arizona, is assumed to be limited to 

100,000 afy by the available capacity of the Yuma Desalting Plant.

Timing

Each of the representative options for the ocean desalination group has unique permitting and 

legal challenges. The Pacific Ocean projects would require California Coastal Commission 

permits that can be challenging to obtain and would significantly impact the timing of the 

project. Similarly the Gulf of California ocean desalination option would require international 

negotiations and also environmental mitigation that could take an unknown amount of time. 

These challenges and uncertainties make it difficult to estimate the timing for both types of 

projects. It is roughly estimated that a 200-million-gallons-per-day (approximately 200,000-afy) 

project could require 5 years of feasibility, 10 years of permitting, and 5 years of 

implementation, totaling 20 years. For the Pacific Ocean desalination near the border in Mexico 

option, feasibility studies have been completed and additional studies are underway. It is roughly 

estimated that a 56,000-afy plant at this location could require 10 years of permitting and 5 years 

of implementation, totaling 15 years.

Desalinating agricultural drainwater in the vicinity of the Salton Sea changes the existing flow 

balance, and therefore compliance with the California Environmental Quality Act and National 

Environmental Policy Act would be required, as well as the acquisition of permits from entities in 

California. Mitigation of some of the impacts of reduced Salton Sea inflows is part of the 

Quantification Settlement Agreement (QSA). Consistency with the QSA would need to be 

evaluated. Although these would all take time, it is assumed that the option could be 

accomplished with 5 years of feasibility, 5 years of permitting, and 5 years of implementation, 

totaling 15 years. Each larger increment of this option was assumed to require an additional 5 

years to implement due to greater potential impacts and permitting review. 

For the brackish groundwater desalination group, both the concept related to municipal utilities 

developing relatively small-scale brackish groundwater desalting plants and the concept of 

refurbishing the Yuma Desalting Plant are proven technologies. Therefore, the timing for these 

projects is limited to 5 years of permitting and 5 years of implementation, totaling 10 years.

Cost

Several recent studies have included cost estimates for ocean desalination facilities. In addition 

to the information available from these studies, water treatment plant conceptual design and cost 

estimating tools were used to estimate treatment costs. The ultimate dollar-per-af cost for these 

options can vary significantly, based on scale and conveyance facility requirements. The larger 

the scale and the closer the delivery location, the lower the unit cost. Capital cost estimates 
Colorado River Basin

Water Supply and Demand Study

F-18 December 2012

ranged from approximately $2.8 to $4.2 billion. The unit annual costs for the representative 

options considered in the Study vary between $1,900 per af and $2,100 per af. 

The same cost tools used to estimate the ocean desalination option group were used to estimate 

the desalination of Salton Sea agricultural drainwater option. Unit capital costs as well as 

electricity, chemicals, maintenance, repair, and replacement costs were assumed consistent with 

the ocean desalination option group. Assuming the drain water total dissolved solids (TDS) is 

approximately 2,500 milligrams per liter and the product water is 700 milligrams per liter, a unit 

annual cost of about $1,000 per af was estimated (capital costs were estimated at $2.1 billion). 

The cost of the brackish groundwater group of options is highly dependent on the assumed 

salinity concentration of the groundwater and the method of disposing the brine stream from the 

reverse osmosis units. Capital costs were estimated at approximately $80 million. The unit 

annual costs for the representative options considered in the Study vary between $600 per af and 

$750 per af. 

Other Key Considerations

In regard to technical feasibility, ocean desalination facilities have been completed in numerous 

locations around the world, but none at the scale described for the larger concepts. Therefore, 

technical feasibility characterization varies based on scale and precedence for similar options. 

When considering long-term viability, there is some concern about the potential for increased 

electricity costs to impact viability. None of the desalination options rate high for operational 

flexibility criteria because these options would have high debt service costs that exist even when 

the option is put into an idle mode. These options rely on exchanges along the river to varying 

degrees, and these exchanges allow the yield to be distributed across numerous locations and 

could result in a change in how the river reaches are operated. These options could potentially 

have adverse impacts when considering hydropower, recreation, and other environmental flowdependent resources. In regard to water quality, these options have the potential to have a 

significant positive impact in reducing salinity levels in locations where lower salinity water is 

delivered. Without more-detailed assessments, neutral conditions were assumed for 

socioeconomics. 

The other key considerations for the agricultural drainwater and brackish groundwater 

desalination groups are similar to those described for the ocean desalination options, with a few 

exceptions. These options are rated higher for technical feasibility because they are on a scale 

more similar to existing desalination operations. Implementation risk and long-term viability are 

also rated higher due to the existing precedent for these types of operations and the reliable water 

source. Agricultural drainwater desalination at the Salton Sea is rated high for energy source 

because of the availability of geothermal energy in this region. 

5.1.9 Characterization Summary

A summary of the characterization findings are shown in figure F-4. The top portion of the figure

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, some large options were broken into 200-kafy steps to reflect 

increasing complexity as project size increases. These steps are denoted numerically, with “step 

1” being the first 200-kafy increment, followed by subsequent steps. In general, a “C” rating is 

typically designated as mostly neutral (yellow); “A” is largely positive (green); and “E” is 

largely negative (red). Refer to appendix F3 for specific criteria descriptions and rating scales. 
Technical Report F — Development

of Options and Strategies

December 2012 F-19

5.3 Reuse

Reuse of existing water supplies was proposed as a method of increasing overall water supply in 

the Basin. Ten options were submitted related to wastewater reuse. The submitted options were 

reviewed and organized into three groups. Representative options were developed for each 

option group to represent the distinct nature of the options within each group. When potential 

yield of a representative option exceeds 200 kafy and the option is scalable, the representative 

option was characterized in progressive 200 kafy “steps” to represent likely project phasing. The 

option groups and representative options are described below. 

Additional detail related to the representative options and specific characterization is included in 

appendix F6. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

5.3.1 Municipal Wastewater Reuse

This group of options includes concepts related to reuse of municipal wastewater in major urban 

areas beyond projects currently planned. The group considers reuse options utilized for nonpotable purpose such as irrigation or for potable purposes through indirect or direct methods. 

One representative Basin-wide option was developed for this group, but includes regional 

differentiations related to types of reuse. For example, non-potable reuse was considered in all 

major municipal areas receiving Colorado River water. However, indirect potable reuse was 

considered for areas in Southern California and Arizona due to the current and already planned 

high levels of non-potable reuse programs. The municipal reuse representative option considers 

reuse for municipal uses including parks. 

Current levels of municipal reuse vary throughout the Study Area. In adjacent areas where 

Colorado River water is essentially used to extinction, such as the Front Range of Colorado, 

increases in supply due to reuse are minimal. In addition, the future demand scenarios for these 

areas assume 100 percent reuse of additional Colorado River supplies. 

Municipal Wastewater Reuse was separated into sub-options of 200-kafy steps to allow for 

incremental characterization of these large-scale options. Nonpotable reuse was assumed to 

occur initially such that the first step is entirely nonpotable reuse. 

5.3.2 Industrial Wastewater Reuse

This group of options considers wastewater flows generated from a variety of industries that are 

not discharged through municipal wastewater systems. These are typically industries that have 

their own water supply and are often outside of municipal limits. The reuse of wastewater from 

various industries was considered. In this case, the only representative option is general 

industrial wastewater reuse.
Colorado River Basin

Water Supply and Demand Study

F-20 December 2012

FIGURE F-4 

Summary of Characterization Ratings for Desalination Options

Desalination (Desal); Gulf of California (Gulf)
Technical Report F — Development

of Options and Strategies

December 2012 F-21

5.3.3 Grey Water Reuse

Grey water is generally defined as untreated wastewater that has not been contaminated by any 

toilet discharge, has not been affected by unhealthy bodily wastes, and does not present a threat 

from contamination by unhealthful processing, manufacturing, or operating wastes (California 

Water Code, 2010). The reuse or recycling of this water at individual homes or communities can 

be used for non-potable purposes. This group of options assumes reuse of water for non-potable 

purposes at individual homes and is limited by the amount of residential wastewater generated as 

well as the seasonal nature of the associated non-potable demand. The representative option is 

described as grey water reuse in adjacent urban areas.

5.3.4 Characterization of Options

Quantity of Yield

For the municipal wastewater reuse group of options, potential demand was estimated based on 

their potential for non-potable reuse. This potential was only examined where wastewater return 

flows do not return to the Colorado River. The potential was reduced by currently planned reuse 

programs and generally by limitations on reuse due to water rights obligations. This method 

resulted in a non-potable reuse potential of about 360,000 afy in the Study Area. For California

and Arizona, indirect potable reuse was assumed to be the most likely reuse method. Between 

the two states, yield estimates are approximately 570,000 afy based on integration limitations 

and preference for non-potable reuse where available. The total estimated reuse potential is 

approximately 930,000 afy. 

Industrial reuse targeted specific industries and byproducts. The target industries largely lie 

within the self-supplied or “self-served industrial” category. Targeting 10 percent of the selfserved industrial demand results in about 40,000 afy of reuse water.

Grey water reuse at individual homes for non-potable purposes could potentially supply about 

178,000 afy by 2060. This rate is based on the assumption that 50 percent of residential indoor 

water use could be considered grey water (washing machines, showers, and sinks) and that grey 

water derived from this use could only be utilized to supply residential non-potable demands. 

These demands are on average approximately 60 percent of total household demand. An 

adoption rate of 50 percent was further assumed.

It is important to note that in many adjacent urban areas, such as the Front Range in Colorado, 

Colorado River grey water is treated and re-diverted for reuse by municipalities or for use by 

other downstream diverters entitled to the return flows under Colorado Water Law. Use of grey 

water for irrigation may reduce treatment costs; however, unless the actual outdoor irrigation 

consumptive use is decreased, there will be no net supply increase to the system. 

Timing

Because traditional municipal wastewater non-potable reuse is commonly practiced in the 

Southwest, these options were assumed to require about 3 years for feasibility, 2 years for 

permitting, and 5 years for implementation for a total of 10 years. Indirect potable reuse options 

included an additional 10 years to reflect both their scale as well as associated permitting and

implementation challenges due to integration with municipal treated water supplies. Each 

subsequent 200-kafy increment of municipal reuse was assumed to require an additional 5 years 

to implement.
Colorado River Basin

Water Supply and Demand Study

F-22 December 2012

Industrial reuse was assumed to be implemented in a similar timeframe to traditional non-potable 

reuse.

Grey water reuse options were also assumed to be implementable within a 10-year timeframe. 

The primary constraint is largely related to legal issues associated with plumbing code 

consistencies and health and safety concerns (individual systems). 

Cost

Costs for municipal wastewater reuse were estimated for each type of reuse (e.g., non-potable 

and indirect potable). Traditional non-potable uses were derived from the augmentation study 

(Colorado River Water Consultants, 2008) with unit annual costs of about $1,500 per af. A 

parametric cost estimating tool was used to directly estimate the indirect potable reuse options, 

resulting in unit annual costs of about $1,800 per af due to additional treatment and distribution 

system costs. Capital costs to treat and convey the indirect potable reuse water were estimated to 

be approximately $4.8 billion. Based on the costs for each increment of municipal reuse, it was 

assumed that non-potable programs would be implemented first, followed by indirect potable 

reuse programs.

The industrial reuse group included treatment of produced water with TDS concentrations on the 

order of 15,000 milligrams per liter. Additional costs for collection and distribution of this water 

resulted in a unit annual cost of at least $2,000 per af. 

Grey water recycling costs were derived from information available at www.greywateraction.org 

and had the highest cost of the reuse options due to the distributed nature of the systems. Water 

produced through this option is estimated to cost $4,200 per af. 

Other Key Considerations

In addition to yield, timing, and cost, the municipal wastewater reuse group of options was 

characterized against several other criteria. In general, reuse is highly feasible and has been 

implemented on similar scales in other places in the region, nation, and the world. Reuse scores 

poorly under operational flexibility due to the likely associated debt service for a stranded asset. 

Energy needs range from 500 kilowatt hours (kWh) per af to 4,300 kWh per af for these options, 

with the indirect potable options having the greatest energy use. All options would have power 

from the grid, resulting in a mix of fuel sources. These projects are generally neutral with respect 

to hydropower production due to the distributed nature of Basin-wide reuse, but at larger scales 

the reuse is concentrated in Southern California and may have impacts due to potential for 

reduced releases from Hoover Dam for exchanges. Reuse options in the Upper Basin could result 

in increases in salinity as experienced in areas where reuse is heavily practiced. The indirect 

potable options would likely improve overall water quality given the removal of salt load

through desalination for these options, but will require effluent disposal of concentrated brines, 

which could be challenging. Recreation impacts are assumed to be largely neutral, and no 

appreciable positive or negative impacts to socioeconomics are noted. 

Industrial wastewater reuse characterizes similarly to municipal wastewater reuse. Energy needs 

would be on the order of 1,600 kWh per af with more treatment required than traditional nonpotable reuse but less than for indirect or direct reuse. Industrial wastewater reuse may also 

require diesel fuel as the significant energy source due to hauling from the distributed locations. 

Grey water reuse also characterizes similarly to municipal wastewater reuse. Grey water reuse 

would score well on operational flexibility in that it would likely be implemented on a case–by- 
Technical Report F — Development

of Options and Strategies

December 2012 F-23

case basis, resulting in little debt service and therefore no associated stranded asset. In addition, 

grey water reuse rated high for permitting and other environmental factors in that it would result 

in reduced wastewater discharge to sewer systems.

5.3.5 Characterization Summary

A summary of the characterization findings are shown in figure F-5. The top portion of the figure

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, some large options were broken into 200-kafy yield steps to 

reflect increasing complexity as project size increases. These steps are denoted numerically, with 

“step 1” being the first 200-kafy increment, followed by subsequent steps (e.g., Municipal1, 

Municipal2, Municipal3.) In general, a “C” rating is typically designated as mostly neutral

(yellow); “A” is largely positive (green); and “E” is largely negative (red). Refer to appendix F3 

for specific criteria descriptions and rating scales.

5.4 Local Supply 

Developing new local supply was proposed to increase the overall water supply of the Basin. 

Four options related to local supply were received. The submitted options were reviewed and 

organized into two groups according to the source of local supply. Each group is described 

below. Because of the scope and level of detail provided in the proposed options, the option 

groups are also used as representative options for the characterization process. 

Additional detail related to the representative options and specific characterization is included in 

appendix F7. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

5.4.1 Coal Bed Methane-produced Water

In the process of developing natural gas resources, poor quality groundwater is typically 

“produced” from natural gas wells. The coal bed methane (CBM) industry has generally 

disposed of produced water at the least possible cost rather than treat and use this potential 

resource. In most cases, CBM-produced waters are disposed by injection into Class II 

underground injection wells. This group of options considers treating the relatively high salinity 

water and using it to augment supply in the Basin. 

5.4.2 Rainwater Harvesting

Rainwater harvesting is the capture, diversion, and storage of rainwater for landscape irrigation 

and other uses. This option group considers how individual household rainwater harvesting can 

increase local supply in some areas of the Basin, with particular emphasis on those areas that do 

not provide return flows to other users downstream. 
Colorado River Basin

Water Supply and Demand Study

F-24 December 2012

FIGURE F-5 

Summary of Characterization Ratings for Reuse Options
Technical Report F — Development

of Options and Strategies

December 2012 F-25

5.4.3 Characterization of Options

Quantity of Yield

Field estimates for CBM-produced water are based on recent CBM development data and 

production estimates combined with unit water production data specific to the Rocky Mountain 

region coal basins. Using the CBM reserves data and a conservative unit water production of 

5 to 10 gallons per million cubic feet of CBM gas, total potential produced water volumes for 

the four major coal basins located within the Basin are projected to be between 161,000 to 

322,000 afy, based on proved reserves, and between 279,000 to 558,000 afy, based on total 

estimated reserves. For the purpose of the Study, it was assumed that CBM wells are installed to 

extract all the reserves over the next 40 years, resulting in between 4,000 afy and 14,000 afy. 

Yield estimates for individual rainwater harvesting are based on normal precipitation in specific 

regions combined with average roof size, landscaped area, and number of households. Using this 

information, a simple rainwater harvesting tool was developed to estimate the potential yield 

from implementation of distributed rainwater harvesting systems. The resulting Basin-wide yield 

estimate is approximately 75,000 afy. 

Timing

A number of CBM wells are currently producing water; however, the infrastructure needed to 

treat and convey the water would first require policy incentives and then construction. 

Additionally, to realize full-scale benefits, more CBM wells need to be developed. For the Study, 

the time required to affect policy incentives was assumed to be 5 years. The needed 

infrastructure to treat and convey the water was assumed to need another 5 years for 

construction, and the development of additional wells could take up to 20 years. Therefore, it 

would take 5 to 10 years to produce some volumes of new water, and up to 20 years for largescale benefits to be realized. Availability of this source will be dependent on continued 

CBM production and therefore it will be subject to market volatility and long-term viability 

issues, increasing supply uncertainty. For the purposes of the Study, it was assumed that 

CBM production would occur over the next 40 years until proven reserves are exhausted. 

Rainwater harvesting is already being used in some areas of the Basin. The concept is currently 

feasible, in many cases does not require permitting, and is simple to implement with very little 

infrastructure. Therefore, in locations where there is not a water rights issue, the 50-percent 

adoption rate used to estimate yield could be achieved within 5 years. 

Cost

Because of typically poor water quality, required treatment facilities are the principal factor in 

capital costs. To treat 500 gallons per minute of CBM-produced water with TDS concentration 

of 15,000 milligrams per liter, approximately $4 million in treatment facilities are required. 

Intensive pre-treatment and reverse osmosis result in estimated operating costs of $600 to 

$635 per afy of produced water. When conveyance is considered, an average cost of $2,000 per 

afy was assumed.

The cost for purchase and installation of a 500-gallon storage tank and irrigation modifications 

was assumed to be $1,000 per household. Because of the limited storage capacity and the 

mismatch in timing of rain events and water demand, harvested rainwater only delivers 

approximately 10 percent of outdoor demand, or approximately 0.02 af per household. As a 

result, the calculated unit cost of water is estimated at $3,150 per afy. 
Colorado River Basin

Water Supply and Demand Study

F-26 December 2012

Other Key Considerations

In addition to yield, timing, and cost, the CBM-produced water option group was characterized 

against several other criteria. National Pollution Discharge Elimination System permits would be 

required to discharge the treated water into the watershed, and modifications to existing permits 

would be needed for brine disposal. Challenges associated with implementation include the 

water source’s dependence on the highly volatile energy sector and the large spacing between 

wells, which increases operating costs and reduces flexibility. Finally, the process is energyintensive. Desalting the water would require approximately 4,700 kWh per af, and transporting 

the water from individual wells to collection sites would most likely be done using trucks. In 

addition, there are legal issues that would have to be addressed in order to implement the use of 

CBM-produced water. 

Aside from the high capital cost for individual households, the rainwater harvesting option group 

is easy to implement, is already practiced in many states, has no energy needs, and, depending on 

state and local laws, does not require any permitting. Nonetheless, in some states this option is 

not currently permissible under state laws. Due to water rights concerns to downstream users and 

state law, rainwater harvesting was not considered for Colorado or Utah. 

5.4.4 Characterization Summary

A summary of the characterization findings are shown in figure F-6. The top portion of the figure 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. In general, “C” is typically designated as mostly neutral (yellow); “A” is largely 

positive (green); and “E” is largely negative (red). Refer to appendix F3 for specific criteria 

descriptions and rating scales.

5.5 Watershed Management

Changes to watershed management have been proposed to increase the overall water supply of 

the Basin. Ten options related to watershed management were received. The submitted options 

were reviewed and organized into five groups according to the specific type of watershed 

management recommendations. Each group is described below. Because of the scope and level 

of detail provided in the proposed options, the option groups are also used as representative 

options. When potential yield of a representative option exceeds 200 kafy and the option is 

scalable, the representative option was characterized in progressive 200 kafy “steps”. 

Additional detail related to the representative options and specific characterization is included in 

appendix F8. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 
Technical Report F — Development

of Options and Strategies

December 2012 F-27

FIGURE F-6 

Summary of Characterization Ratings for Local Supply Options
Colorado River Basin

Water Supply and Demand Study

F-28 December 2012

5.5.1 Tamarisk Control

Control of invasive tamarisks has been proposed for riparian areas to reduce their overall 

consumptive use and increase streamflow in the Colorado River. Removal of tamarisk is 

proposed in riparian benches where water that would have otherwise contributed to streamflow is 

being consumptively used by tamarisk. A comprehensive report on the state-of-the-science of 

tamarisk management in the Basin is the Colorado River Basin Tamarisk and Russian Olive 

Assessment prepared for the Basin States by the Tamarisk Coalition (2009). It is the primary 

basis of the yield estimates. 

5.5.2 Forest Management

A large percentage of the runoff from the Basin is derived from forests, particularly in Colorado. 

Previous studies and information have demonstrated that areas in which forest cover is reduced 

by clear-cutting or fires have shown dramatically increased amounts of runoff. This is the result 

of reduced interception, decreased evapotranspiration, and sometimes reduced permeability of 

the soil surface. The magnitude of increased runoff over affected areas may be as much as 

100 millimeters, or 4 inches, per year. The forest management group of options would entail the 

replacement of mature forests that have been cleared by harvesting, fires, or insect infestations 

with stands of replacement growth more likely to be favorable for generating runoff. The 

demonstration of the viability of this option starts in Colorado because the majority of flow of 

the Colorado River system results from runoff generated in that state. Even though Arizona, New 

Mexico, Utah, and Wyoming have significant forested areas, the annual amounts of runoff from 

the forested areas in these states is much lower than in Colorado. The forested area in Colorado 

covers more than 21,000,000 acres, most of which is in the Basin and generates an average 

annual runoff of approximately 11 mafy. 

The Forest Management representative option was separated into sub-options of 200-kafy steps 

to allow for incremental characterization of this large-scale option. 

5.5.3 Brush Control

Brush control involves reducing brush and therefore reducing consumptive use by vegetation 

communities. There is some evidence that removal of brush and replacement with native grasses 

improves runoff conditions, particularly in areas receiving more than 18 inches of rainfall 

annually. The Basin includes as many as 100,000 square miles of land under the control of the 

Bureau of Land Management (BLM) that is vegetated to varying degrees by brush. The brush 

control group of options recommends various techniques available for brush removal including 

chemical spraying, chaining, roller chopping, root plowing, grubbing, and controlled fires. For 

all types of removal, reseeding with native grasses is required. Most removal methods must be 

repeated at approximately 8- to 10-year intervals to prevent new growths of brush from emerging 

and dominating. 

5.5.4 Dust Control

These options propose to control land-based dust sources that contribute to dust accumulation on 

snow, which changes the albedo of the snow resulting in earlier snowmelt (Painter et al., 2007 

and 2010; Skiles et al., 2012) and more evaporative moisture losses. By implementing measures 

to reduce the accumulation of dust on snow, lower evaporative losses are anticipated. 
Technical Report F — Development

of Options and Strategies

December 2012 F-29

The Dust Control representative option was separated into sub-options of 200-kafy steps to allow 

for incremental characterization of this large-scale option. 

5.5.5 Weather Modification

The weather modification group of options was based on two practices. The first is by cloud 

seeding, particularly by introduction of atmospheric silver iodide to serve as condensation nuclei 

that would increase snowfall over mountain regions. The second is to create more inland seas, 

thereby increasing the amount of atmospheric moisture due to increased evaporation. Because 

neither data nor investigations were submitted to support the viability of the second option, the 

primary focus was on evaluating the feasibility of weather modification through cloud seeding. 

Winter cloud-seeding operations have been practiced throughout the West since the late 1940s. 

In recent years, ongoing cloud-seeding operations have been documented in at least five of the 

seven states within the Basin.

The Weather Modification representative option was separated into sub-options of 200-kafy 

steps to allow for incremental characterization of this large-scale option. 

5.5.6 Characterization of Options

Quantity of Yield

The total tamarisk acreage in the Basin has been mapped at 250,000 acres. This value is

considered low because a significant amount of the data are point data with no actual acreage 

assigned to this information. If one-fourth of the total tamarisk acreage can be managed by a 

tamarisk removal program, the total program acreage is about 60,000 acres. As a Basin-wide 

average, normalized for climate, elevation and latitude estimates of water savings due to reduced 

evapotranspiration by removal of tamarisk and replacement by other species are roughly 0.54 af

per acre per year. At this rate of water savings, conversion of 60,000 acres from tamarisk to other 

species would save approximately 30,000 afy of consumptive water use. 

As a simplifying assumption for the forest management group of options, it was estimated that if 

5 percent of the forested area in Colorado were managed to increase runoff and the magnitude of 

the increased runoff was 4 inches, more than 300,000 afy of increased flow would be generated. 

However, the increased yield is expected to rapidly decline as new growth begins to replace 

harvested areas.

Average runoff in the areas of BLM land considered for the brush control group of options is 

minimal, typically in the range of 0.05 to 0.1 inch annually. Therefore, total runoff from this area 

is approximately 250,000 to 500,000 afy. For evaluation purposes, it was assumed that brush 

control could potentially increase runoff by 10 percent. The resultant maximum benefit that 

could be expected if brush control were implemented on all BLM land in the Basin would be 

25,000 to 50,000 afy. 

Referenced modeling studies by the National Oceanic and Atmospheric Administration (Painter 

et al., 2010) and others indicate that as much as 800,000 afy might be recovered by controlling 

the amount of dust accumulating on snow. Due to the uncertainty about the effectiveness of 

measures to control the generation of dust and prevent its deposition on snow, the amount of 

additional runoff that could be obtained was evaluated to be no more that 50 percent of the total 

potential amount, or 400,000 afy. Two steps of this representative option were derived based on 

targeting key areas of emissive lands versus more-distributed dust control. 
Colorado River Basin

Water Supply and Demand Study

F-30 December 2012

For the weather modification group of options, it is estimated that cloud seeding six major 

runoff-producing areas could produce between 1.1 and 1.8 mafy in the Upper Basin and an 

additional 830,000 kafy in the Lower and adjacent basins. Of the total, it has been estimated that 

approximately 1.7 mafy would be available to reduce deficits or meet new demands. Due to the 

large potential of this option, sub-options of 200,000 afy each were characterized to reflect 

potential issues associated with the scale of the option. 

Timing

Several ongoing studies and programs have focused on tamarisk control. It is assumed that 

implementing this option group would involve a new program that would build upon earlier 

efforts. A programmatic approach to permitting is assumed that would result in evaluation of 

feasibility within 2 years, obtaining required permits within 5 years, and then implementation 

over a 5-year time frame. Therefore, it is possible to see full-scale benefits from the tamarisk 

control group of options within 12 years.

The forest management group of options is feasible only if the approach is to perform selective 

harvesting of mature trees in areas where the density is too high, combined with understory 

clearance to minimize forest fires. Other areas of focus would be revegetation of lands that have 

been deforested by forest fires or insect infestations. The time to evaluate the feasibility of forest 

management activities was estimated to be 7 years. The timeframe for permitting was estimated 

to be 3 years, largely due to the consideration that these forest management activities are 

currently being practiced, although not for purposes of increasing runoff. The timing for 

implementation of forest management practices was estimated at 10 years to conform to time 

frames experienced with other forest management measures. Therefore, the total time for 

development of the forest management group of options is estimated to be 20 years. An 

additional 10 years is assumed to implement the program at a full scale.

Brush control on BLM land involves conversion of vegetative cover from trees such as mesquite 

and juniper to native grasses. This has been implemented over small areas, but not over the large 

area envisioned by this option. The implementation would also require programmatic and 

financial support from federal and state agencies as well as coordination with private contractors 

who are using the BLM land for grazing. The time requirements for evaluation of feasibility 

were estimated to be 5 years, 5 years for permitting, and 5 years for phased implementation. 

Therefore, the total time required for availability of increased runoff from brush control on BLM 

land would be at least 15 years. 

The essential consideration in determination of timing for developing increased runoff through 

dust control is that dust management practices would have to be implemented over a relatively 

large portion of the Colorado Plateau and the Great Basin. The large areal extent led to an 

estimate of the timeframe to evaluate effectiveness as 5 years, followed by 5 years for 

permitting, and 5 years for the first phase of implementation, for a total of 15 years. An 

additional 10 years is assumed for the next increment of implementation due to the more 

distributed nature of management. The essential element of implementation is the widespread 

adoption of practices to minimize wind erosion over large areas. This is most likely to be 

accomplished through financial, regulatory, and educational measures promoted at both federal 

and state levels. 

Weather modification programs have been in effect for many years throughout the West, 

including in the Basin. Based on these existing practices, no additional time would be required 
Technical Report F — Development

of Options and Strategies

December 2012 F-31

for feasibility or permitting of smaller-scale projects. Implementation of smaller-scale projects 

could be completed in 5 years, with each larger increment assumed to require an additional 

5 years for implementation. 

Cost

The Tamarisk Coalition has estimated that the costs of water saved by tamarisk management 

range from $260 to $1,050 per af (Tamarisk Coalition, 2009) with a Basin-wide average annual 

cost of less than $400 per af. A unit annual cost of $400 per af is assumed. 

For the forest management group of options, the extent to which existing forest roads are 

available (to provide better access for vegetation harvesting and replacement) will have a 

significant impact on cost. One study indicated that the cost could be around $500 per acre after 

considering potential revenue benefits by selling harvested products to processing mills. 

Additional estimates of costs experienced by the U.S. Forest Service for similar management 

activities ranged from $114 to $786 per acre, with estimates for individual forest areas from 

$215 to $1500 per acre on a 20-year rotation. The median cost value was $875 per acre. 

Assuming a cost of $1,000 per acre on a 20-year rotation, with annual maintenance costs of 

about 10 percent of that amount, the unit annual cost of additional runoff generated is 

approximately $500 per af. 

For brush control on BLM land, the preferred method of control would be spraying of the brush 

with herbicides formulated for control of the selected variety of brush, followed by mechanical 

removal of the brush, and then seeding with native grasses to revegetate the affected areas.

Chemical spraying costs about $30 per acre and has to be repeated at about 10-year intervals 

(Research & Planning Consultants, 2000). If yields could be achieved and maintained, annual 

cost would be approximately $7,500 per af. 

For the dust control option, it was assumed that conversion of the land to native grasses would 

require practices similar to enrollment in the U.S. Department of Agriculture Conservation Reserve 

Program. Costs were estimated for clearing the land by root plowing and then reseeding with 

native grass. It was also assumed that periodic maintenance by spraying would be required at 

approximately 10-year intervals. Based on the costs of these practices, an average cost of $15 per 

acre per year was derived. Implemented over an area of 10,000 square miles, the cost per af of 

increased yield is $500. The first phase of a dust control program is assumed to target those areas 

of the Colorado Plateau that are the most prolific in generating dust emissions and would 

produce greater yield per acre of management than the second phase, so cost per afy is estimated 

at $220. 

For weather modification by cloud seeding, separate cost estimates were derived from the 

California Department of Water Resources and from the documentation provided in the Study of 

Long-Term Augmentation Options for the Water Supply of the Colorado River System (Colorado 

River Water Consultants, 2008). The California reference indicated that cloud seeding produced 

300,000 to 400,000 af of additional runoff at a cost of around $7 million. The investigations 

associated with the augmentation study led to a annual cost estimate of $20 to $30 per af. Higher 

costs were estimated for larger-scale programs due to reduction in yield enhancement for less 

productive regions or storms for similar levels of investment. 
Colorado River Basin

Water Supply and Demand Study

F-32 December 2012

Other Key Considerations

For the tamarisk control option group, some studies have indicated that the species replacing 

tamarisk may have consumptive water use levels as great as the tamarisk unless the revegetation 

process is actively managed, resulting in a low rating for long-term viability. However, one 

would not consider managing tamarisk to increase water supply unless the replacement 

vegetation was native and used less water. Active management is also required to ensure that 

tamarisk do not reinvade the replacement species in the riparian zone. Reinvasion is reduced 

along regulated rivers because the ability of seed to be dispersed by flood in river valley bottoms 

(and germinated in the wet zone) is minimized. Studies have also shown that tamarisk stands 

along alluvial channels are effective in anchoring stream banks and preventing stream erosion. 

One unintended consequence of tamarisk control may be an increase in stream erosion in 

affected reaches, resulting in a low rating for water quality until replacement vegetation is 

established. If the option is practiced only on the upland terraces, this adverse impact would be 

minimized. Also, tamarisk control was rated poorly for energy source because the equipment 

used for implementation would likely rely on diesel and gasoline fuel. A potential benefit of 

tamarisk control is improved access to the areas of control for recreational purposes because

replacement species are more amenable to recreational activities, but removal of tamarisk

currently being used by endangered and protected species may be an important consideration. 

There are other benefits in terms of riparian habitat improvements associated with this option.

Forest management is a mature science. Objectives have generally been to increase lumber 

production, maintain habitat and ecosystems, or limit erosion. The primary objective of forest 

management has rarely been to improve runoff conditions. As a result, the overall technical 

feasibility, implementation risk, long-term viability, and operational flexibility are uncertain.

Forest management would require overcoming substantial implementation and permitting 

hurdles. Although energy needs would be relatively low, the source of energy would likely be 

diesel and gasoline fuel.

Although the brush control group of options is considered in terms of potential benefit through 

implementation of brush control over a large area, the specific process used for brush control to 

best optimize resultant impacts on hydrology, vegetation, and habitat is very site-specific. Brush 

management over a large scale is expensive and requires ongoing maintenance to ensure that the 

benefits of brush removal are being realized. For example, when brush is removed and replaced 

with native grasses, proper grazing management is required for several years to make sure that 

the grasses are well-established. When not done properly, brush control can adversely affect 

hydrology and grazing and habitat values. For these reasons, technical feasibility, 

implementation risk, long-term viability, and operational flexibility were all given low ratings.

Other key criteria for the dust control option were also ranked similarly to the other watershed 

management options. 

Weather modification ranked high for operational flexibility because it can be easily 

implemented on various scales from year to year. When considering hydropower, water quality, 

recreation, and other environmental criteria, options that resulted in more water in headwaters 

locations were ranked positively. Socioeconomic impacts were generally judged to be neutral 

because all options created some jobs, although the number of jobs might vary from year-to-year. 
Technical Report F — Development

of Options and Strategies

December 2012 F-33

5.5.7 Characterization Summary

A summary of the characterization findings are shown in figure F-7. The top portion of the figure 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, some large options were broken into 200-kafy yield steps to 

reflect increasing complexity as project size increases. These steps are denoted numerically, with 

“step 1” being the first 200-kafy increment, followed by subsequent steps (e.g., Dust1, Dust2, 

Dust3.) In general, a “C” rating is typically designated as mostly neutral (yellow); “A” is largely 

positive (green); and “E” is largely negative (red). Refer to appendix F3 for specific criteria 

descriptions and rating scales. 

5.6 Municipal and Industrial Water Conservation 

Development of additional M&I water conservation was proposed to further reduce the overall 

M&I water demand in areas currently relying upon water supply from the Colorado River. A 

number of M&I conservation options were submitted for consideration in the Study, with several 

of the submitted options suggesting specific conservation measures. Many of these measures 

have been implemented at a number of locations in the Study Area. 

Because levels of current and future conservation vary throughout the Study Area, different 

levels of potential savings are possible for a given conservation measure. These savings range 

from essentially no savings where measures have been fully implemented to significant savings 

where measures have not been implemented or where adoption rates are relatively low. 

Disaggregating the savings potential by conservation measure and individual location was 

beyond the scope of the Study. Instead, M&I conservation measures were considered for the 

entire Study Area with the acknowledgement that, despite state and regional differences in 

current levels of conservation and potential for future conservation, additional conservation is 

achievable on a Study Area-wide basis. Likewise, it is assumed that additional conservation is 

due to an “active” incentive-based program, such as paying for conversion of turf to xeriscape, 

toilet replacement, etc. The total potential yield of M&I conservation exceeds 200 kafy, therefore 

the representative option was characterized in progressive 200 kafy “steps”. 

Additional detail related to the representative options and specific characterization is included in 

appendix F9. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 
Colorado River Basin

Water Supply and Demand Study

F-34 December 2012

FIGURE F-7 

Summary of Characterization Ratings for Watershed Management Options

Weather modification (Weather mod)
Technical Report F — Development

of Options and Strategies

December 2012 F-35

5.6.1 Overall Approach

These levels of additional M&I demand reduction could be implemented through use of 

progressively ambitious water conservation best management practices (BMPs) and adoption 

rates targeting residential indoor; commercial, institutional, and industrial (CII); outdoor 

landscaping; and water loss demand. Example BMPs and a more-complete discussion of the 

approach to characterizing the additional M&I conservation option can be found in appendix F9. 

Not included in this approach are water use restrictions that may be used as a local response to 

short-term drought. These practices are commonly included in municipal drought management 

plans and may include activities such as enhanced public education and outreach, tiered levels of 

voluntary and mandatory restrictions, short-term rationing, and short-term water rate increases. 

These drought response measures have not been included because they vary significantly by 

geographic location and reflect a short-term agency-specific response to supply challenges rather 

than a long-term measure for balancing supply and demand. 

Many of these BMPs have already been enacted throughout the Study Area, resulting in 

significant conservation savings. For example, a recent study of municipal deliveries of Colorado 

River water (Pacific Institute, 2011) found that most of the municipalities receiving Colorado 

River had experienced significant reductions in per capita water deliveries for the period 1990 

through 2008. A number of States such as California and Utah have programs in place that target 

a certain amount of reduction over time (e.g. California’s 20x2020 program). Likewise, a 

number of individual communities, such as Phoenix, Albuquerque, Denver, and Las Vegas, have 

specific M&I conservation goals. As such, representative BMPs are available to varying degrees 

throughout the Basin. 

In order to examine the potential for additional M&I conservation and to explore the range of 

costs and other factors, three levels of conservation were considered based on assumed levels of 

reductions and adoption rates for residential indoor, CII, landscape, and water loss. Table F-2 

presents the assumptions for Level 1, Level 2, and Level 3 conservation. The assumptions in 

table F-1 were derived from state of Colorado (Colorado Water Conservation Board, 2011) and 

California (CALFED, 2006) approaches and applied to Study Area projected demand to result in 

a Basin-wide estimate of potential water savings. The assumptions were derived for purposes of 

the Study and do not necessarily reflect realistic or achievable local conservation goals. 

Although performing a municipality or regional level analysis of the M&I conservation is 

beyond the scope of the Study, the assumptions are generally consistent with regional approaches 

considered in Colorado (Colorado Water Conservation Board, 2011) and California (CALFED, 

2006). 

5.6.2 Characterization of Options

Regional Considerations

The potential M&I water conservation measures are assumed to apply to the Study Area, but 

significant differences in potential water savings exist between geographies due to the current 

level of conservation adoption, commercial and industrial base, and climate. In addition, because 

return flows may provide flow for indirect recycling for some in-Basin locations, indoor 

conservation has little to no net effect on water resources to meet M&I water demand in these 

locations. For in-Basin locations, only reductions in consumptive use will reduce overall 

Colorado River system demand as the return flows from the urban areas is returned to the 

Colorado River or a tributary. 
Colorado River Basin

Water Supply and Demand Study

F-36 December 2012

TABLE F-2

Study Area M&I Conservation Assumptions

Level 1 Level 2 Level 3

Residential Indoor

Indoor gallons per capita per day (gpcd) 60 50 40

Adoption rates 50% 60% 70%

Example types of BMPs: Public education programs, conservation-oriented plumbing and building codes, residential 

water surveys, high efficiency showerheads and faucets, ultra low-flow toilets, efficient clothes washers, meter 

retrofits, etc. 

CII

Target reduction in demand 15% 25% 30%

Adoption rates 50% 60% 70%

Example types of BMPs: Public education programs, conservation-oriented plumbing and building codes, green 

building codes, CII surveys and audits, high efficiency faucets and fixtures, ultra low-flow toilets, high-efficiency 

clothes washers, dishwasher high-efficiency pre-rinse spray valves, meter retrofits, efficiency in industrial processes 

and cooling, etc. 

Outdoor Landscaping

Target reduction in demand 15% 25% 35%

Adoption rates 50% 60% 70%

Example types of BMPs: Public education programs, conservation-oriented pricing, large landscape water surveys 

and audits, evapotranspiration-based irrigation controllers, large landscape separate metering, irrigation efficiency 

improvements, conversion of turf to lower water use landscaping, etc.

Water Loss

Target water loss 7% 7% 7%

Adoption rates 50% 60% 70%

Example types of BMPs: Utility water loss control, supply system audits and leak detection programs, etc.

In many of the major urban areas receiving Colorado River or tributary water, the overall water 

supply served to communities consists of a significant portion of other supplies (other surface 

supplies, groundwater supplies, reuse, etc.) in addition to Colorado River or tributary water. In 

most of these out-of-Basin areas, the supplies are commingled in the water supply and 

distribution systems before delivery to the consumer. Due to the distributed nature of water 

conservation, water conservation will reduce the overall demand on these supplies, but is not 

likely to result in a one-for-one reduction in Colorado River demand. Likewise, in many adjacent 

areas, water exported from the Basin is reused essentially to extinction. Municipal conservation 

in these areas reduces the amount of water available for reuse, and does not result in a one-forone reduction in Colorado River demand. 

Implementation Approaches

The primary implementation approach under consideration for M&I water conservation is an 

incentive-based program. Public education programs, regulations dictating standard practices 
Technical Report F — Development

of Options and Strategies

December 2012 F-37

for new development, and incentive-based programs encouraging more efficient water use 

are typically implemented. These programs provide the necessary incentives (financial or 

otherwise) to achieve the levels of conservation. Financial incentives provide a cost share for 

implementation of BMPs and have been widely used to facilitate conversion to higher-efficiency 

fixtures and toilets. These types of mechanisms are anticipated to continue to be widely used to 

achieve higher levels of conservation in areas served by Colorado River water. Non-incentive 

based approaches such as plumbing code changes and public education programs are considered 

as well.

Quantity of Yield

As described in Technical Report C – Water Demand Assessment, M&I water conservation 

measures have been implemented at many locations throughout the Basin, resulting in significant 

reductions from historical per capita use. The future demand scenarios include, to varying 

degrees, by both scenario and location, some portion of passive conservation (resulting from 

outside entities/programs, such as federal standards) and active conservation (resulting from 

active state and local programs). Conservation considered in the demand scenarios ranges from 

about 300 kafy to more than 1.1 mafy, depending on the assumptions within each scenario 

regarding degree of per capita water demand reductions3. Additional conservation beyond that 

included in the demand scenarios was considered in the three additional conservation levels 

(Levels 1, 2, and 3). The demand reduction from each of these levels was computed by applying 

the assumptions in table F-1 to the M&I demand over the entire Study Area. Table F-3 presents 

the potential additional savings of Colorado River water under these assumptions. For all 

scenarios, these values represent the additional demand reduction by 2060. 

TABLE F-3

Reductions in Colorado River Basin Demand (afy) for Each Demand Scenario and Conservation Level at 2060

Conservation Level

Current 

Projected 

(A)

Slow 

Growth

(B)

Rapid

Growth

(C1)

Rapid 

Growth 

(C2)

Enhanced 

Environment

(D1)

Enhanced 

Environment

(D2)

Savings Assumed in 

Demand Scenarios

478,000 296,000 621,000 1,048,000 1,052,000 1,114,000

Additional Savings from M&I Conservation

Level 1 185,000 187,000 207,000 56,000 44,000 55,000

Level 2 576,000 504,000 681,000 427,000 238,000 383,000

Level 3 1,051,000 888,000 1,258,000 960,000 654,000 908,000

Significant water conservation has occurred in the recent decades through most urban centers in 

the Study Area. The M&I water conservation savings realized in the demand scenarios and 

potential additional measures will likely occur at a lower annual rate than what has been 

observed in recent historical periods due to differing types of conservation measures and greater 

adoption rates that will need to be included. In addition, as water use efficiency increases, the 

ability to further reduce use diminishes and the uncertainty with respect to future yield increases. 

 

3 The level of M&I conservation included in the water demand scenarios is estimated by first re-computing the M&I demands under each 

scenario, assuming the 2015 gpcd value from that scenario. The difference in the M&I demand in 2060 with gpcd held at 2015 levels from the 

M&I demand in 2060 under the actual demand scenario is the amount of M&I conservation achieved under that demand scenario. 
Colorado River Basin

Water Supply and Demand Study

F-38 December 2012

As noted for other options, in order to represent the challenges associated with increasing scale, 

when options exceed 200-kafy yield or demand reduction, they were generally assumed to be 

implemented in 200-kafy steps. For example, for the Current Projected (A) scenario, 

M&I conservation options would be available in five steps of 200 kafy each and a final sixth step 

of at 51 kafy. These steps are assumed to proportionally implement progressive amounts of the 

individual levels noted in the table. For example, for the Current Projected (A) scenario, the first 

increment of conservation will implement 185 kafy of “Level 1” practices and 15 kafy of “Level 

2” practices. 

Timing of Option Availability

Because the M&I water conservation options would be ramped over time, each of the options 

could begin implementation with benefits starting to accrue within 5 years. The potential savings 

of the options would be small in the early years of implementation and grow over time. Ultimate 

savings for each level are assumed to occur in 2060, with the savings progressively ramping 

upward from 2015 through 2060. However, it is possible that adoption rates could be slower or 

faster than those included in the conservation-level assumptions. In addition, conservation Level 

2 would in all likelihood need to have adopted all conservation Level 1 measures, and 

conservation Level 3 would need to have adopted the majority of the measures and adoption 

rates from Level 2. 

Costs

Table F-4 presents the estimated costs per af of water conservation savings to implement the 

suite of BMPs for each conservation level. The costs range from roughly $350 to $1,400 per afy

reduction in demand. These costs do not reflect any associated reduction in revenue due to 

reduced water sales. CII and outdoor landscaping water conservation measures represent the 

most cost-intensive measures. Based on the assumption that the water conservation savings result 

in proportional savings to all supplies contributing to Study Area delivery, the demands for 

Colorado River water may only be reduced by about 40 percent of the total Study Area demand 

reduction. However, it is assumed that the cost to Colorado River water users is solely for the 

reduction (benefit) that they achieved and that “other” beneficiaries would pay for their portion 

of the overall benefit. It is quite possible that M&I water conservation in some regions outside of 

the hydrologic basin may result in little to no reduction in Colorado River demand due to cost 

considerations within the region’s water supply portfolio. 

TABLE F-4

Estimated Costs per af Demand Reduction for Each Conservation Level at 2060

Costs (afy) for Demand Reduction by Category 

Level 1 Level 2 Level 3

Residential Indoor $350 $450 $550

CII $550 $900 $1,200

Outdoor Landscape $700 $1,050 $1,400

Water Loss $350 $350 $350

Weighted Average $500 $750 $950
Technical Report F — Development

of Options and Strategies

December 2012 F-39

Other Key Criteria

In addition to yield, timing, and cost, the M&I conservation options were characterized against 

several other criteria. In general, the initial reductions are feasible and comparable examples 

exist in areas of the Southwest and in other arid regions of the world. Subsequent reductions 

become progressively more difficult to achieve and maintain. Programs of this scale are 

underway at state levels, but have not been demonstrated on basins of the scale of the Colorado 

River in North America. It is not anticipated that permitting or legal changes will be required to 

implement these options, but agreements on the methodology and institutional structure will be 

required to implement these options in this multi-jurisdictional basin. Some policy changes may 

be required to fully implement the Level 3 assumptions, and implementation on such a large

scale might require landscape conversion to xeriscape. There is some implementation risk in that 

yields will fluctuate over time and programs will require continuous funding to maintain overall 

results. Many conservation measures are based on achieving behavior changes in the way water 

is valued and used. The realized conservation savings associated with these measures may be 

dependent on future economic, social, and political conditions that maintain and strengthen these 

behavior changes. However, once savings are realized through most measures they generally can 

be maintained, resulting in long-term viability of the options. These options were rated high with 

respect to operational flexibility because the programs can be stopped at any time without 

incurring significant debt service or resulting in stranded assets. There are no inherent energy 

needs for the M&I conservation options in that they result in reduced demand and reduced need 

to treat and deliver water. For the highest levels of conservation, there could be some 

socioeconomic issues as turf is converted to xeriscaping. 

5.6.3 Characterization Summary

A summary of the characterization findings are shown in figure F-8. The top portion of the figure 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, for implementation purposes, some large options were broken 

into 200-kafy yield steps to reflect increasing complexity as project size increases. For 

conservation, the three conservation levels resulted in demand reduction (yield) from about 

600,000 afy to 1.2 mafy. These resulting yields were implemented in 200-kafy steps. These steps

are denoted numerically, with “step 1” being the first 200-kafy increment, followed by 

subsequent steps. 

In general, a “C” rating is typically designated as mostly neutral (yellow); “A” is largely positive

(green); and “E” is largely negative (red). Refer to appendix F3 for specific criteria descriptions 

and rating scales. 

5.7 Agricultural Water Conservation 

Options were submitted proposing agricultural water conservation to reduce the overall water 

demand in areas currently relying upon water supply from the Colorado River. These options 

ranged in type from specific conservation mechanisms or BMPs (e.g., improved irrigation 

efficiencies, modernization, conveyance system efficiencies, changes in types of crops under 

irrigation, etc.) to general implementation approaches to achieve further water conservation 

(e.g., water pricing or water transfers). These options were used to develop agricultural water 

conservation representative options. The representative options were parsed into 200 kafy 

“steps” to represent likely project phasing. 
Colorado River Basin

Water Supply and Demand Study

F-40 December 2012

FIGURE F-8 

Summary of Characterization Ratings for M&I Conservation Options
Technical Report F — Development

of Options and Strategies

December 2012 F-41

Additional detail related to the representative options and specific characterization is included in 

appendix F10. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

5.7.1 Overall Approach

The concepts received were first organized into six Basin-wide agricultural water conservation 

mechanisms that reflect different types of activities that could generate water savings in the 

agricultural sector. These agricultural water conservation measures consist of advanced irrigation 

scheduling, deficit irrigation, on-farm irrigation system improvements, controlled environment 

agriculture, conveyance system efficiency improvements, and fallowing of irrigated lands. 

However, because the method of implementation is important for realization of water savings, 

two implementation approaches that could be used to encourage or incentivize adoption of these 

water conservation mechanisms were used to develop representative options— (1) Basin-wide 

agricultural conservation through a federal or state incentivized program to encourage 

agricultural water use efficiency, and (2) Basin-wide agricultural conservation with water 

transfers on a willing transferor-willing transferee basis that promotes water conservation and/or 

short-term or permanent fallowing of irrigated lands to transfer conserved water to a transferee 

for a similar or different use.

For purposes of the Study, each of the various conservation measures were examined as a Basinwide potential, but in reality the measures will have important regional limitations and in some 

cases may be mutually exclusive. The various measures should not be considered to be additive. 

Because levels of current agricultural conservation measures vary throughout the Study Area, 

different levels of potential savings are possible for a given conservation measure. These savings 

range from essentially no savings, where measures have been fully adopted, to significant 

savings, where measures have not been adopted or where adoption rates are relatively low. 

Disaggregating the savings potential by conservation measure and individual location was 

beyond the scope of the Study.

In addition, the conservation measures could produce different amounts of savings depending on 

the location in the Basin, implementation approach, and combination of measures; the total 

quantities were estimated as an aggregate for each implementation approach. Up to 1 mafy of 

potential savings by 2060 was considered for each approach (conservation and conservation with 

transfers) although the approaches are not considered additive. 

5.7.2 Characterization of Options

Regional Considerations

The potential agricultural water conservation measures are assumed to apply to the overall Study 

Area, but significant differences in potential water savings exist between in-Basin and adjacent 

irrigated areas due to water budget considerations, application efficiency and consumptive use 

considerations, and downstream uses dependent on return flows. In addition, applied water 

requirements and evapotranspiration vary across the Basin depending on elevation, climate, soils, 

irrigation methods, crop types, and other factors. Differences between in-Basin and adjacent area
Colorado River Basin

Water Supply and Demand Study

F-42 December 2012

conservation potential and applied water requirements were considered, but the assessment of 

conservation was not planning area or state-specific. 

Implementation Approaches. The two primary implementation approaches considered are 

conservation through incentive-based programs and conservation with water transfers. For either 

approach, program controls are necessary to ensure that water conservation investments provide 

measurable returns in verifiable water savings. Water conservation program controls should 

address the following issues: 

• Conserved water needs to be measurable and easily observable and, where costs are not 

prohibitive, should be verified by volumetric water use measurement. 

• Legal mechanisms must be in place to protect conserved water in-stream for intended uses,

especially in areas where insufficient stream flow currently limits downstream water users 

from exercising their full diversion rights. 

• Controls may be needed to prevent expansion of effectively irrigated areas associated with 

water conservation investments. 

• A healthy agricultural economy must be maintained and associated policy implications 

considered. 

A key distinction between incentive-based programs and water transfers as defined here is 

whether a legal transfer of water or water rights is involved. The incentive-based programs are 

assumed to be accomplished without legal transfer of water or water rights, whereas the water 

transfers specifically revolve around legal transfers of water or water rights.

Incentive-based Programs. Incentive-based programs can take different forms depending upon 

the type of water conservation option and the type of collaborator (e.g., water user versus water

purveyor). Generally, this option involves providing financial incentives through: 

• Grants or low-interest loans to construct infrastructure projects

• Cost-share payments to offset the costs of irrigation system conversion 

• Incentive payments to growers that adopt water conservation practices and provide 

documentation of management practices (payments to implement specific observable 

practices)

• Incentive payments based on a reduction in volume of water diverted or consumptively used 

(no specific practice is required, but savings must be measured relative to a baseline) 

• Water pricing changes

Several existing federal incentive programs could be applicable under this approach. 

Water Transfers. Water transfers represent the legal transfer of water or water rights from one 

use to another. Within an agricultural water use framework, transfers can be implemented on a 

temporary basis (one growing season) from year to year through the acquisition or lease of water 

or a water right or on a permanent basis essentially through the acquisition or sale of water or a 

permanent water right. Typically, water transfers are negotiated on a willing-transferor, willingtransferee basis and can be implemented on a direct transferor-transferee arrangement or can be 

facilitated through a water bank. 
Technical Report F — Development

of Options and Strategies

December 2012 F-43

Quantity of Yield

The methods used to quantify potential yield from agricultural conservation all distinguish 

between conserved water that would have been lost to the Basin versus conserved water that is 

simply re-routed within the Basin. Generally, any savings in water that would have been 

exported from the Basin is counted as reduced depletion and therefore potential yield; within the 

Basin, only reductions in consumptive uses are counted as potential yield. 

Due to the "supply-limited" nature of irrigation water use in the Upper Basin and the high degree 

of sequential reuse of return flow, it is expected that agricultural water conservation savings in 

these areas will be limited due to downstream return-flow-dependent uses. For a given funded 

water conservation project, a portion of the field-scale water savings will likely be demanded by 

junior downstream users that have historically relied on these return flows. Exceptions to this 

condition will occur in the most downstream areas of irrigation projects where downstream 

ability to reuse return flows is limited. Additionally, there may be distinctions between surface 

and groundwater return flow impacts, with downstream users being more immediately and 

directly dependent upon surface return flows. The estimated quantities of yield and cost per afy

of water conserved discussed below and presented in table F-5 are based on field-scale estimates 

and are not discounted for return-flow-dependent uses until they are shown in table F-5. 

The estimated quantities of yield, before discounting for the effect of return-flow-dependent use, 

are discussed in this section for each of the agricultural water conservation measures. Table F-5 

summarizes the percent reduction in consumptive use or total diversion associated with 

implementing a unit amount of each measure. These estimates are explained in the following 

sections.

TABLE F-5

Estimated Potential Water Savings Percentages at the Farm Scale for Each Agricultural Water Conservation Measure

Water Conservation Measure

Reduction in 

Consumptive Use 

(In-Basin)

Reduction in Total 

Diversion

(Outside Basin)

Advanced Irrigation Scheduling 0% 13%

Deficit Irrigation 13% 20%

On-Farm Irrigation System Improvements 0% 20% 

Conveyance System Efficiency Improvements 1% 20% 

Controlled Environment Agriculture 50% 50%

Irrigated Lands Fallowing 40 to 100% Up to 100%

Water savings for reductions in total diversion have not been discounted for effects of return-flow-dependent 

use.

Because the conservation measures could produce different amounts of savings depending on the 

location in the Basin, implementation approach, and combination of conservation measures, the 

total quantities were estimated as an aggregate for each implementation approach rather than a 

summation of individual conservation measures. Up to 1 mafy of potential savings by 2060 was

considered for either Basin-wide conservation with or without transfers but is not considered
Colorado River Basin

Water Supply and Demand Study

F-44 December 2012

additive. By comparison, the summation of potential water savings from each conservation 

measure totals 2.44 mafy when accounting for non-consumptive use savings outside the Basin 

and ignoring return flow impacts. This amount is reduced to 833,000 afy when only consumptive 

use savings are considered under each approach category. Table F-6 summarizes the potential 

agricultural water conservation savings by measure and implementation method. 

TABLE F-6

Estimated Potential Water Savings at the Farm Scale for Each Agricultural Water Conservation Measure 

Water Conservation Measure

Reduction in 

Consumptive Use

(af) 

Reduction in Total 

Diversion

(af) 

Advanced Irrigation Scheduling 0 270,000

Deficit Irrigation 100,000 130,000

On-Farm Irrigation System Improvements 0 490,000

Conveyance System Efficiency Improvements 0 820,000

Controlled Environment Agriculture 13,000 13,000

Irrigated Lands Fallowing 720,000 720,000

TOTAL 833,000 2,443,000

Timing of Option Availability

Because the agricultural water conservation options would be ramped over time, it was 

considered that the improvements to irrigation management, on-farm irrigation improvements, 

and changes in crop consumptive use could occur in as early as 10 years. Large infrastructure 

projects, including conveyance system efficiency improvements and controlled environment 

agriculture, were estimated to require at least 15 years before full implementation due to the 

planning, permitting, design, and construction needs. 

Costs

Costs for implementing agricultural water conservation measures will vary regionally and with 

different levels of conservation programs. Costs were estimated based on review of existing 

programs implementing such measures. 

Based on the estimates reported by Cooley et al. (2010), the costs for improved irrigation 

scheduling and deficit irrigation were approximately $100 per afy and $43 per afy and the cost of 

on-farm irrigation efficiency improvements was $390 per afy. These estimates were based on 

total water savings, not reduction in consumptive use. 

Achievements of reduced consumptive use through rotational or permanent fallowing were

estimated based on existing fallowing programs and administration costs. The IID has recently 

offered $125 per af to growers for fallowing fields to provide conserved water for transfer and 

for mitigation purposes (IID, 2012). This price applies to the full reduction in applied water. 

Costs for conveyance system efficiency improvements vary substantially depending on the 

characteristics of the existing delivery system. System improvement options developed for the 

IID Efficiency Conservation Plan (2007) ranged from $140 to $800 per af of reduced diversion. 

Controlled environment agriculture costs vary by crop type, hydroponic or aquaponic system, 

and installation technique. Initial capital costs are more than 10 times higher than traditional 
Technical Report F — Development

of Options and Strategies

December 2012 F-45

agricultural operations, with construction costs of $3 to $7 per square foot reported for relatively 

large-scale greenhouses (U.S. Department of Agriculture, 2003; Mississippi State University

Extension Service, 2009). Based on an assumed 1.5 af per acre per year savings, unit costs are 

likely approaching $6,000 per af. This cost would be offset to some extent by improved crop 

yield, quality, and price, but these benefits are highly dependent on market conditions. 

In general, it is anticipated that agricultural conservation programs would be implemented from 

least costly to more costly and that these costs will vary somewhat by the implementation 

program and specific BMPs considered. It is assumed that “Conservation” is more focused on 

on-farm and delivery system improvements, whereas “Conservation with Transfer” is more 

focused on fallowing. These assumptions are based on current implementation programs and 

legal structures that favor specific practices depending on whether the conserved water is 

transferrable. Table F-7 presents the estimated costs for about 1 mafy of savings when 

200,000-afy steps are considered. Note that the initial step of “Conservation” is dominated by 

On-Farm conservation with other measures such as System conservation and Fallowing being 

implemented in greater proportions in subsequent levels. When transfers are considered, 

however, fallowing is the dominant measure. In both cases, costs increase with increasing yield 

requirements. 

TABLE F-7

Agricultural Conservation Annual Costs per af of Savings by Implementation Type

Savings

(mafy) Conservation1 Conservation with Transfer2

Step 1 0.2 On-Farm $150 Fallowing $250

Step 2 0.4 $300 $400

Step 3 0.6 System $500 System $500

Step 4 0.8 $600 $600

Step 5 1.0 Fallowing $750 On-Farm $750

1 Begins with programs more heavily weighted toward On-Farm Measures (Deficit Irrigation, 

Advanced Irrigation Scheduling, On-Farm System Improvements) but includes some portions of 

System Improvements and Fallowing in subsequent steps. 

2 Begins with programs more heavily weighted toward Fallowing but includes some portions of 

System Improvements and On-Farm in subsequent steps. 

Other Key Criteria

In addition to yield, timing, and cost, the agricultural water conservation options were 

characterized against several other criteria. A summary of the findings for all criteria is shown in 

figure F-9. In general, these options are technically feasible and examples exist in areas of the 

Southwest and in other arid regions of the world. Controlled environment agriculture is unlikely 

to be economically feasible on a large scale under foreseeable circumstances. Irrigation 

management and efficiency improvement programs have been undertaken at district and state 

levels, but have not been demonstrated in basins on the scale of the Colorado River in North 

America. It is not anticipated that significant permitting will be required to implement these 

options. However, these options will affect diversion patterns, return flow quantities and 

locations, and groundwater recharge. These changes could generate legal challenges. 
Colorado River Basin

Water Supply and Demand Study

F-46 December 2012

Coupling agricultural conservation with a transfer mechanism can have varying degrees of 

political and legal complexities depending on the nature of the transfer. For example, an Upper 

Basin banking concept was explored in the Study that assumes water generated through 

agricultural conservation is transferred to a downstream conceptual water bank near Lake 

Powell. Transfers of this nature would have significant policy and legal challenges. The 

characterization ratings shown in figure F-9 do not reflect transfers associated with banking 

arrangements and assume all saved water in the Upper Basin States is made available to local 

water users within the priority system. 

All options have some implementation risk in that yields will fluctuate over time and programs 

will require continuous funding to maintain overall results. Controlled environment agriculture 

has additional challenges due to the very large capital requirements: at an average $5.43 per 

square foot (Mississippi State University Extension Service, 2009), more than $2.6 billion would 

be required to construct the facilities for 11,000 net acres of production. Additional long-term 

challenges would include maintaining sufficient revenue to pay the debt service and operations. 

For the other options, once savings are realized they can be maintained, resulting in long-term 

viability. 

The non-structural options were rated high with respect to operational flexibility, because the 

programs can be stopped at any time without incurring significant debt service or resulting in 

stranded assets. However, structural (including irrigation infrastructure) options do not have high 

operational flexibility. Non-structural agricultural water conservation options do not require 

energy, but on-farm irrigation improvements generally will require energy for pressurizing 

sprinkler and drip systems or for pumping recycled tailwater. Greenhouses require pressurized 

irrigation and may require heating and cooling systems, depending on location and season of 

operation. Agricultural water quality issues primarily relate to fertilizers and pesticides in return 

flows to surface or groundwater. All of the options reduce return flows, so they could have 

positive effects on water quality. All options would likely have generally positive or neutral 

impacts on hydropower and recreation. Impacts on other environmental factors are uncertain. In 

some cases, the lower diversions could be positive by leaving additional flow in streams; in other 

cases, reduced return flows could affect environmental resources such as riparian vegetation 

along canals and drains that have come to rely on the return flow. Structural options such as 

system conveyance improvements and controlled environment agriculture would have 

construction-related impacts.

All of the options would require some additional spending in local communities to implement, 

and would therefore support local economic activity. Only the reduced consumptive use option 

was rated low on socioeconomics due to the potential effect on agricultural communities under 

long-term fallowing and reduced crop production. It is possible that these effects can be 

mitigated by taking a Basin-wide rotational approach to this option such that individual 

communities do not experience the impacts in a sustained manner. 

5.7.3 Characterization Summary

A summary of the characterization findings are shown in figure F-9. The top portion of the figure 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the figure shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, some large options were broken into 200-kafy yield steps to 

reflect increasing complexity as project size increases. These steps are denoted numerically, with 
Technical Report F — Development

of Options and Strategies

December 2012 F-47

FIGURE F-9 

Summary of Characterization Ratings for Agricultural Water Conservation Options

Agricultural (Ag)
Colorado River Basin

Water Supply and Demand Study

F-48 December 2012

“step 1” being the first 200-kafy increment, followed by subsequent steps. In general, a “C” 

rating is typically designated as mostly neutral (yellow); “A” is largely positive (green); and “E”

is largely negative (red). Refer to appendix F3 for specific criteria descriptions and rating scales. 

For purposes of consistency with the other options that were separated into sub-options of 

200-kafy steps, both agricultural conservation with and without transfers were assumed to be 

implemented through steps of 200 kafy. 

5.8 Energy Sector Water Use Efficiency 

Options to improve the water use efficiency of the energy sector have been proposed to reduce 

the water demand in the Basin. Four options related to energy water use efficiency were 

received. The submitted options were reviewed and organized into two groups according to the 

different concepts proposed for reducing water demand. The option groups are described below. 

Additional detail related to the representative options and specific characterization is included in 

appendix F11. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

5.8.1 Conversion of Power Plants to Air Cooling

This option group includes removing the evaporative cooling systems at the 15 largest power 

plants in the Basin and installing air-cooling systems. When evaluating this option, the following 

obstacles to retrofitting existing water-cooled power plants with air-cooling systems were 

considered: 

• High cost of installing air-cooling systems 

• Effect of air cooling on plant power output during hot weather 

• Effect of air cooling on plant efficiency

• Applicability of air-cooling technology to the plant systems designed for water- cooled 

service

• Larger site footprint required for air-cooled system 

• In general, air cooling reduces the overall capacity to produce power by about 10 to 15 

percent, with disproportionate reductions during the warmer months when peak load often 

occurs. 

5.8.2 Water Use Efficiencies in the Oil and Gas Industry

This concept addresses the need for a reliable water source for oil and gas development, and 

suggests options for ensuring sufficient supplies through a number of improved efficiency 

measures. Options suggested increased regulation on oil and gas exploration to protect water 

resources from contamination, and use of treatment processes to make the byproduct water 

available as a new supply instead of disposing the water to evaporation lagoons or deep wells. 

Another option involves maximizing efficiency of water use at oil and gas refineries. Although 
Technical Report F — Development

of Options and Strategies

December 2012 F-49

described here for completeness, the treatment and use of the natural gas byproduct water is 

included in the local supply category and is not characterized here. Also, increased reuse of 

industrial type waters is covered in the industrial reuse category and not characterized here. 

5.8.3 Characterization of Options

Quantity of Yield

Developing yield estimates for these options includes researching historical and estimated future 

use of water by power plants. The 15 largest power plants in the Basin consume approximately 

167,000 afy of water. Assuming 95 percent of that amount could be saved by converting to air 

cooling, about 160,000 afy of yield is potentially available with this concept.

Timing

Feasibility studies to identify the estimated amount of power generation loss due to reductions in 

efficiency and plans for making up those losses are assumed to take up to 3 years. Revised air 

quality and noise permits are required for the alternate equipment, and it could take 2 or more 

years to acquire those permits. Detailed design and construction could take another 5 years, with 

a total timeframe of at least 10 years. 

Cost

The cost for the decommissioning of wet cooling systems and construction of air-cooling 

systems, plus the increased cost of operation of the power plants, were estimated in the Study of 

Long-Term Augmentation Options for the Water Supply of the Colorado River System (Colorado 

River Water Consultants, 2008). The study estimated the costs at approximately $1,300 per af for 

plants of 2,000 MW and greater capacity and as much as $4,000 per af for plants smaller than 

1,000 MW capacity. The costs will vary at each facility, but the estimated weighted average

annual cost is about $2,000 per af of water saved.

Other Key Considerations

The technology behind improving energy water use efficiency is proven and reliable, resulting in 

a high feasibility rating. In regard to implementation, there is likely to be opposition from the 

power industry due to increased costs and reductions in efficiency, and possible opposition from 

the public due to potential increases in costs of energy to the greater community. Long-term 

viability is believed to be high because once the technology is installed and paid for, water 

demand is permanently reduced. Due to the investment and infrastructure required, operational 

flexibility is limited because the criterion penalizes options with high debt service costs that exist 

even when the option is put into an idle mode. Although the option conserves water use in the 

energy generation process, it is projected to reduce energy generation by 10 to 15 percent. 

Applying the “fence line” concept described earlier to the option characterization implies that the 

reduced generation is outside of the “fence line,” resulting in a neutral score. When considering 

hydropower, water quality, recreation, and other environmental impacts, this concept could result 

in reduced diversion for these Upper Basin power plants, and increased water in the river. It is 

also unknown how this water would be used by others, which could result in a change in how the 

downstream river reaches are operated. Due to these unknowns, neutral conditions were assumed 

for these criteria. Socioeconomic impacts are difficult to fully assess because jobs will be created 

with all of these options. There is also likely to be a combination of positive and adverse impacts 

in the exporting regions. Without more-detailed assessments, neutral conditions were assumed 

for socioeconomics. 
Colorado River Basin

Water Supply and Demand Study

F-50 December 2012

5.8.4 Characterization Summary

A summary of the characterization findings are shown in figure F-10. The top portion of the 

figure shows the estimated quantity of yield, earliest timing of implementation, and estimated 

cost. The bottom portion of the figure shows the 17 criteria and associated ratings (“A” through 

“E”) for each option. In general, “C” is typically designated as mostly neutral (yellow); “A” is 

largely positive (green); and “E” is largely negative (red). Refer to appendix F3 for specific 

criteria descriptions and rating scales.

5.9 System Operations 

Options dealing with modified system operations have been proposed to increase the overall 

water supply, decrease demand, reduce evaporation losses, and improve efficiency within the 

Basin. The submitted options were reviewed and organized into three option groups according to 

the overarching concept driving the new or modified operation. Representative options were 

developed for each option group to represent the distinct nature of the options within each group. 

When potential yield of a representative option exceeds 200 kafy and the option is scalable, the 

representative option was characterized in progressive 200 kafy “steps”. The option groups and 

representative options are described below. 

Additional detail related to the representative options and specific characterization is included in 

appendix F12. A more complete discussion of the criteria and ratings descriptions is provided in 

appendix F3. Attachment A of appendix F3 contains more detailed descriptions of the ratings. 

Attachment B provides the methods used for completing the unit cost calculations. Attachment C 

presents the detailed characterization information and is available on the compact disc that 

accompanies this report and on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

5.9.1 Evaporation Control Covers

This group of options includes physical and chemical methods to reduce evaporation from the 

major canals and reservoirs. Physical covers would incorporate solar photovoltaic panels to 

simultaneously reduce evaporation and generate electricity. Concepts involving chemical covers 

include the introduction of a chemical to the water surface of large reservoirs to reduce the 

evaporation rates of the reservoirs. 

Based on these distinct concepts, three representative options were developed: 

• Solar Panel Canal Covers

• Solar Panel Reservoir Covers

• Chemical Type Covers

5.9.2 New Water Storage

These options involve the construction or expansion of reservoir projects in order to increase the 

amount of system storage available. There are two representative options in this group: 

• New Water Storage

• Improved Groundwater Management 
Technical Report F — Development

of Options and Strategies

December 2012 F-51

FIGURE F-10 

Summary of Characterization Ratings for Energy Water Use Efficiency Options
Colorado River Basin

Water Supply and Demand Study

F-52 December 2012

5.9.3 Modified Reservoir Operations 

Recommendations for changing current operations were proposed to improve water management 

in the Basin. While many of the characterization criteria apply to these options, the options’ 

complexity limits the ability to select ratings for each criterion. The application criteria are 

discussed qualitatively in the following section. 

The submitted options were reviewed and organized into five representative options according to 

the specifics of the recommendation: 

• Reduce Reservoir Evaporation 

• Prioritize Lake Mead Storage

• Maximize Hydropower Generation

• Operating for Environmental Purposes 

5.9.4 Characterization of Options

For the system operations category of options, only the options in the Evaporation Control 

Covers and New Water Storage underwent a characterization with ratings assigned to each 

criterion. Due to their technical and legal complexity, the options that comprise the Modify 

Operations group were not assigned ratings. However, available information on relevant criteria 

are discussed below. 

Quantity of Yield

For the evaporation control covers options, estimated yields varied based on the scope of 

application. Expected savings due to reduced evaporation are 18,000 afy for canal covers, 

200,000 afy for reservoir covers, and 850,000 afy for chemical type covers. 

Adding additional reservoirs or other storage could result in additional yield. Storing 1.2 million 

af in the proposed high-altitude Union Park Reservoir instead of in Lake Powell would result in 

some additional yield due to reduced losses from evaporation. Based on existing evaporation 

rates at each location, approximately 20,000 afy could be saved under ideal conditions. Because 

specific locations have not been identified for additional storage reservoirs to capture unused 

water already released from Lower Basin reservoirs, the additional volume of water made 

available cannot be accurately estimated.

The improving groundwater management option is related to recovering groundwater in areas 

where long-term sustainable groundwater pumping is not being practiced. This option does not 

produce “new” yield for the system. 

Typical evaporation at Lake Powell is around 50 inches per year. Similarly, evaporation at Lake 

Mead is estimated to average approximately 80 inches per year (U.S. Geological Survey 

[USGS], 2006). The reservoirs have differing surface area to storage characteristics, and there 

are numerous other operational objectives that must be met; therefore, it is not possible to 

perform simple calculations to estimate potential benefits of evaporation savings associated with 

revised operations. A detailed modeling assessment was not performed for the Study. However, 

historical studies (Colorado River Consultants, 2008) and analysis conducted for this Study 

suggest that between 0 and 300,000 afy could be saved through reoperation. For the remaining 

representative options in the modified reservoir operations group, no new yield is expected. 

Prioritizing Lake Mead storage would result in higher evaporation losses and negative yield to 

the system. 
Technical Report F — Development

of Options and Strategies

December 2012 F-53

Timing

To better understand the potential of the physical cover options, a 2-year feasibility study should 

be considered. If deemed feasible and the concept was aggressively pursued, 2 years of 

permitting followed by 5 years of construction is plausible, totaling about 10 years. An additional 

5 years is anticipated to be required for the floatovoltaic concepts to address potential issues with 

covering the lakes. Because use of chemical covers to reduce evaporation is not common 

practice, feasibility studies followed by pilot programs on smaller water bodies would be 

expected before being attempted on a large scale. Also, extensive permitting would likely be 

required to show (with confidence) that adding the chemical to the water does not have negative 

impacts on water quality, public health, or the ecosystem. It is assumed that the studies and small 

pilot-scale test could take place within 5 years. Next, a larger-scale pilot of an additional 5 years 

may be required. Next, permitting and additional testing would likely take 3 years, and 

application could take another 2 years. Therefore, 15 years could be required for full- scale 

implementation. 

All aspects of the proposed CCP (Central Colorado Project) (New Water Storage) are currently 

feasible from a technical standpoint. Feasibility analysis of the concept has already begun and 

could be completed within 3 years; however, construction of a new dam and modified flows in 

the upper reaches of the basin would require significant permitting and most likely an 

environmental impact statement. Allowing for 15 years to complete the permitting process and 5 

years to construct the facilities, the CCP would take approximately 20 years to implement.

Because other specific projects have not been identified for additional storage to capture unused 

released water, the time required to implement the project cannot be estimated.

The modification of Lakes Powell and Mead operations to reduce evaporation losses has 

significant legal and political implications. Any operational modifications could not occur until 

after 2026, when the 2007 Interim Guidelines (Colorado River Interim Guidelines for Lower 

Basin Shortages and the Coordinated Operations for Lake Powell and Lake Mead (U.S. 

Department of the Interior [DOI], 2007) expire. Furthermore, re-operating either reservoir solely 

to reduce evaporative losses is not consistent with either facility’s authorized purposes. The other 

representative options in this group are all technically feasible but require changes to existing 

operating agreements, permitting, and must be within existing authorizations. 

Cost

SPG Solar performed a pilot study and published the results showing that 3 acres of floatovoltaic 

coverage has an estimated capital cost of $5 million and generates about 1 MW of power 

(SPG Solar, 2007). Assuming the photovoltaic panels have a 15-year life and are amortized at 

4.125 percent, the annual cost of the $5 million installation is about $450,000 per year. 

Assuming the power generated can be sold at $0.05 per kWh, the power generation is worth 

$135,000 per year. Assuming 5 feet per year evaporation reduction, a very rough estimate of 

costs is $20,000 per af. 

In the case of chemical covers, the costs include airplanes, fuel, pilots, aircraft maintenance, and 

the chemical product. Assuming chemical application every 10 days and two planes for chemical 

application, annual O&M is on the order of $38 million. Amortizing the cost of purchasing or 

leasing the airplanes ($3.8 million) and estimating the annual costs of the other cost items results 

in a rough estimated unit cost of about $100 per af. 
Colorado River Basin

Water Supply and Demand Study

F-54 December 2012

According to the information provided in the option submittal, construction of the Union Park 

Reservoir would cost approximately $400 million. For the purposes of the Study, it has been 

assumed that other facilities considered in the plan, including pipelines and pump stations 

between the new and existing reservoirs, would cost an additional $200 million to construct. It is 

also assumed that the cost of operations would be significantly reduced by the revenue generated 

from energy production. Based on these assumptions and considering a yield of 20,000 afy, the 

unit cost of saved water is approximately $2,250 per af of conserved water.

Assuming the cost per unit of water conserved would be half as efficient as the recently 

completed Warren H. Brock Reservoir System, the option to create a reservoir to capture unused 

releases is estimated to cost about $500 per af. 

The annualized unit cost of improved groundwater management is not applicable because no 

additional yield is realized. 

The concept requiring reoperation of the river system between Lake Powell and Lake Mead to 

reduce evaporation requires no new facilities. However, there would likely be significant costs 

associated with the changes in timing of water deliveries, hydropower generation, and ecological 

and recreational impacts. Due to their complexity, these costs were not estimated for purposes of 

the Study. The remaining option groups relating to modifying operations of existing reservoirs 

were estimated to generate no additional yield. Therefore, cost estimates are not applicable for 

these option groups. 

Other Key Considerations

In addition to yield, timing, and cost, solar panel cover type options were characterized against 

several other criteria. In regards to technical feasibility, a neutral rating was given because

floating solar panels have been implemented previously, but not at the proposed scale. 

Permitting, legal, and policy considerations are expected to be positive or neutral for options 

related to covering the canals, but more challenging for options that physically cover the lakes. 

In regards to long-term viability, covering canals is viewed to have few challenges, but 

physically covering the lakes is viewed to be more challenging related to potential loss of

permits even after initial implementation. Operational flexibility is related to the ability to put the 

concept in idle in wet years without negative consequences, and installing physical covers does 

not have that degree of flexibility. In regards to energy needs, the solar panel covers actually 

generate energy. In regards to hydropower, concepts that reduce evaporation in reservoirs can 

later increase hydropower production. Moderate improvements to water quality are anticipated 

for all evaporation reduction options due to higher river flows that reduce salinity concentrations.

Recreation is likely to be impacted due to the physical covers limiting access to part of the lakes. 

Conversely, reducing evaporation will likely increase lake levels and may positively influence 

shoreline recreational access. Environmental impacts for the concepts related to physically 

covering the lakes are unknown, but impacts related to changing sun exposure might be possible. 

Socioeconomic impacts are difficult to fully assess because jobs will be created with these 

options, but there is also likely to be a combination of positive and negative impacts when 

considering more than just job creation. Without more-detailed assessments, neutral conditions 

were assumed for socioeconomics.

In regards to technical feasibility, chemical covers do not characterize as well as physical covers 

due to the limited amount of published literature studying whether the concept would work on 

large reservoirs the size of Lake Mead or Lake Powell that are located in hot, dry and windy 
Technical Report F — Development

of Options and Strategies

December 2012 F-55

climates. The option scores poorly on permitting due to potential pilot testing that may be 

required to confirm that adding the chemicals will not have a negative impact on the ecosystem. 

The chemical cover option did score better than the physical covers option for operational 

flexibility because in wet years it is possible to halt operations and stop the practice of adding the 

chemicals to the water. Implementing the chemical cover concept requires regular introduction 

of the chemical to the lake via airplanes and therefore requires energy in the way of airplane fuel.

Adverse impacts to recreation are expected because of reduced access to the reservoirs. 

Socioeconomic impacts are difficult to fully assess because jobs will be created with these 

options, but there is also likely to be a combination of positive and negative impacts when 

considering more than just job creation. Without more detailed assessments, neutral conditions 

were assumed for socioeconomics.

Additional key criteria for the pumped storage CCP option include permitting, operational 

flexibility, and energy needs. No recent precedent exists for successfully permitting such a 

facility in the proposed region in the recent past, and the project has had significant organized 

opposition for the past 30 years. Although there are no technical feasibility issues with 

operational flexibility, the debt service for the capital costs would still be required in years when 

less revenue could be generated. This is problematic because the debt is proposed to be serviced 

by power-generating revenues dependent on the normal reservoir operations. Last, the unused 

releases water reservoir concept is difficult to characterize without a more-detailed plan. The 

concept is dependent on very specific conditions that may not exist elsewhere in the Basin.

The option to modify reservoir operations to reduce evaporation would require distinctly 

different operations than are currently in place. Therefore, long-standing policies that would have 

wide impacts to Basin stakeholders would need to be reconsidered. This option would also 

reduce or at least change the flows through the Grand Canyon, which could have environmental 

impacts. 

Options to prioritize Lake Mead storage would have significant environmental, recreational, and 

policy issues. There would likely be significant public opposition to lowering Lake Powell 

resulting from impacts on legal obligations and policy objectives, because Lake Powell provides 

the mechanism for the Upper Basin to satisfy its compact obligations. 

5.9.5 Characterization Summary

A summary of the characterization findings are shown in figure F-11. The top portion of 

the figure shows the estimated quantity of yield, earliest timing of implementation, and estimated 

cost. The bottom portion of the figure shows the 17 criteria and associated ratings (“A” through 

“E”) for each option. As noted previously, some large options were broken into 200-kafy yield 

steps to reflect increasing complexity as project size increases. These steps are denoted 

numerically, with “step 1” being the first 200-kafy increment, followed by subsequent steps. In 

general, a “C” rating is typically designated as mostly neutral (yellow); “A” is largely positive

(green); and “E” is largely negative (red). Refer to appendix F3 for specific criteria descriptions 

and rating scales.
Colorado River Basin 

Water Supply and Demand Study

F-56 December 2012

FIGURE F-11 

Summary of Characterization Ratings for System Operations Options
Technical Report F — Development

of Options and Strategies

December 2012 F-57

5.10 Water Transfers, Exchanges, and Banking 

Water transfers, exchanges, and banking have been proposed to increase the efficient use of 

existing supplies in the Basin. This group consists of options that are reflected in the following 

representative options: 

• Water Transfers and Exchanges

• Guided Water Markets

• Upper Basin Water Banking

• Lower Basin Water Banking

• Groundwater Banking 

Due to their complexity and the inability to develop representative options indicative of all water 

banking or transfer-type options, these options have not been assigned ratings for the 17 criteria.

Water transfers and banking options generally require working in conjunction with conservation 

options (agricultural or M&I) in order to generate the water to be transferred or banked. The 

characterization of the options to conserve water is described in the respective conservation 

sections of this report, M&I Water Conservation, and Agricultural Water Conservation. 

5.10.1 Water Transfers and Exchanges 

Water transfers are a voluntary change in the way water is distributed among water users.

Intrastate transfers can be temporary or long-term changes in points of diversion, place of use, or 

purpose of use due to a transfer or exchange of water or water rights (California Water Code, 

2010). Water rights in the Basin are governed by a complex structure of federal laws and 

agreements that collectively form the Law of the River, which governs the allocation of water to 

and among states and in certain cases among water users, and state water rights structures, which 

allocate water to individual water right holders within states. 

Water transfers can consist of a temporary lease or permanent sale of water or a water right by 

the water right holder, a lease of the right to use water from the water right holder, or a sale or 

lease of a contractual right to water supply. Water transfers can also take the form of long-term 

contracts for the purpose of improving long-term supply reliability. Typically, temporary water 

transfers have durations of 1 year or less, whereas long-term water transfers have durations of 

more than 1 year. It should be noted that the nature of these transfers reflects certain legal and 

policy changes that are more challenging than would be expected solely with implementation of 

conservation measures. 

There are several methods used to make water available for transfer. Some of these methods 

include the following: 

• Reducing the existing consumptive uses of water through crop idling, crop shifting, or water 

use efficiency measures to make water available. 

• Reducing return flows or seepage from conveyance systems that would otherwise be 

irrecoverable for downstream beneficial uses. 

• Pumping groundwater (groundwater substitution) instead of using surface water delivery and 

transferring the surface water rights. 
Colorado River Basin

Water Supply and Demand Study

F-58 December 2012

• Transferring water from storage that would otherwise have been carried over to the following 

year. The expectation is that the reservoir will refill during subsequent wet seasons. 

• Banking available water and transferring previously banked groundwater either by directly 

pumping and transferring the banked groundwater or by pumping the banked groundwater 

for local use and transferring surface water that would have been used locally to another user. 

Various legal constraints must be adhered to, depending on existing federal and state regulations 

and laws, to permit the transfer of water from one location to another. The physical infrastructure 

needed to convey or exchange the water from the existing user to the new user must be in place, 

and all infrastructure owners must be included in transfer negotiations. Depending on the nature 

of the transfer, more-significant political and legal challenges may exist. 

Historically, water transfers in the Basin have taken the form of either permanent agricultural 

land fallowing (“buy and dry”) to transfer water to a different purpose of use, temporary 

agricultural land fallowing agreements to meet M&I uses during drought or multiple-year 

periods, or transfers through conveyance system and on-farm efficiency measures. Flows used by 

downstream water users or riparian environmental purposes may be maintained in both timing 

and magnitude. 

Some of the largest recent examples include the Colorado Big Thompson Project, San Diego 

County Water Authority–IID Water Transfer Agreement, and the MWD/Palo Verde Water 

District Forbearance and Fallowing Program. All three of these examples transferred water used 

from agricultural purposes to urban use. The Colorado Big Thompson Project included a large 

number of small quantity transfers from individual users along Colorado’s Front Range 

(Colorado Water Institute, 2011). The San Diego County Water Authority–IID Water Transfer 

Agreement transferred up to 200,000 afy from Imperial Valley agricultural use to San Diego 

County urban use through a combination of land fallowing and efficiency-based water 

conservation measures. Similarly, the MWD/ Palo Verde Water District program transferred up 

to 110,000 afy from use in the Palo Verde Valley to Southern California urban use through crop 

rotation and land fallowing. 

Although the vast majority of water transfers have occurred between agricultural users or 

between agricultural and urban users, some transfers have occurred to transfer water from 

agricultural uses to environmental purposes. The water transfer options propose to seek new 

transfer agreements to optimize transactions for water supply reliability and environmental 

purposes. 

5.10.2 Guided Water Markets

During prolonged and severe droughts, some water users in the Upper Basin may be curtailed in 

order to meet the obligations under Article III(d) of the Compact. Instead of relying only on 

seniority of rights to manage shortages, this option would seek to maximize opportunities for 

using economically beneficial transactions to secure necessary reductions of consumptive water 

uses. The proposed program would work with related federal programs to maximize 

environmental and agricultural benefits throughout the Upper Basin. With a strategic, guided 

approach, water market transactions could be proactively used to meet demand reduction goals. 

Basically, such guided markets would seek to give irrigators who have low profit margins or who 

have less-productive lands within their operation early opportunities to participate in the market, 

reducing pressure on more-profitable irrigation operations that might otherwise be subject to 
Technical Report F — Development

of Options and Strategies

December 2012 F-59

cutbacks due to junior water rights. As an example of how this concept could work with existing 

programs, the Salinity Control Program could be used in combination with market-based, 

compensated transactions with willing sellers to prioritize reductions in irrigation on lands that 

contribute high levels of salinity to further reduce salinity loading in the Basin. Other variations 

of this concept include creating individual state banks and exchanges and allowing temporary 

exchange from irrigation to municipal uses during extreme drought conditions. 

The most likely source of newly available water would come from large irrigators with low 

profit margins or less-productive lands. Assuming 3 feet of consumptive water use per acre, 

fallowing 33,000 acres of alfalfa or similar crops in the Upper Basin may yield as much as 

100,000 afy. However, studies of consumptive water use for alfalfa in the Upper Basin vary, 

with some showing lower consumptive use. Additional fallowed acreage may be required to 

meet the assumed 100,000 afy yield. 

Because the need for this approach could involve changes to existing laws, and possibly to 

interstate agreements as well, about 10 years of feasibility and permitting work would be 

required for implementation of the proposed program. Additionally, implementation would likely 

require several years due to the unprecedented nature of the program. For the purposes of the 

Study, it was assumed the program could be operating in as few as 15 years. 

The costs associated with this option include the purchase or lease of water or water rights, and 

the lease of local reservoir storage space. Based on existing sources, the cost of water rights is 

highly variable depending on the region. In 2001, the estimated value of a permanent water right 

in the San Juan Basin was $3,000 per af, and Colorado-Big Thompson water rights were valued 

at $10,000 per af in 2010. The cities of Aurora and Colorado Springs have lease storage space in 

Pueblo Reservoir at values between $20 and $60 per afy. For the Study, it was assumed water 

rights could be purchased for a one-time cost of $4,000 to $8,000 per af and storage for 5 years 

would cost $50 per af per year. Amortized over 50 years, the resulting cost is approximately 

$600 per af. 

5.10.3 Upper Basin Water Banking

This option proposes that a similar concept to the Intentionally Created Surplus (ICS) program in 

the Lower Basin be applied in the Upper Basin. This option creates an Upper Basin water bank 

in either Lake Powell or in an off-stream groundwater bank to increase protection against 

curtailment in the Upper Basin. In conjunction with the water bank, various conservation (M&I, 

agricultural, and energy) efforts across the Upper Basin would be coordinated for the purpose of 

yielding water to store in the bank. In order to ensure the conserved water is credited to the bank 

entirely, agreements amongst and within those Upper Basin States would be required to 

“shepherd” that water to Lake Powell or other storage facilities in the Upper Basin. In doing so, 

there are likely to be benefits for various ecological and recreational resources that depend upon 

in-stream flows. Significant legal and policy issues would need to be overcome in order to 

successfully implement and operate such a program. These challenges would be in addition to 

those of conservation measures chosen to generate water for the bank. As such, implementing 

this option would be more challenging than implementing a number of its individual 

components. However, for the Study analysis it was assumed that such a program could be in 

place near 2020, which is likely well before there is significant risk of Upper Basin curtailment 

as estimated in the system reliability analysis (Technical Report G – System Reliability Analysis 

and Evaluation of Options and Strategies). 
Colorado River Basin

Water Supply and Demand Study

F-60 December 2012

A representative option that adds more specificity to the concepts described above was 

developed in order to include this option in the portfolio modeling of the system reliability 

analysis. The modeling assumptions associated with this representative option are provided in 

Technical Report G – System Reliability Analysis and Evaluation of Options and Strategies, 

Appendix G-2, Colorado River Simulation System Modeling Assumptions. In summary, the 

representative option consists of two tiers comprising M&I conservation and energy water use 

efficiency (tier 1) and short-term rotational fallowing (tier 2) in which the water saved is 

shepherded to Lake Powell or other storage facilities in the Upper Basin. This banked water is 

then used to protect against curtailment in the Upper Basin. The process of shepherding the water 

results in increased reliability for ecological and recreational resources while the banked water 

provides curtailment protection. 

From the quantification of conservation options independent of this specific option, there was 

assumed to be Basin-wide potential for approximately 1 mafy of conservation in each the 

agricultural and M&I sectors by 2060. Considering the geographical distribution of demand, 

there is an assumed potential for approximately 250 kafy of M&I conservation and 400 kafy of 

agricultural conservation by 2060 in the Upper Basin. Additionally, there is assumed to be up to 

160 kafy of water conservation potential in the energy sector by 2060 within the Upper Basin. 

5.10.4 Lower Basin Water Banking

The 2007 Interim Guidelines (implemented an ICS mechanism to provide for the creation, 

accounting, and delivery of conserved system and non-system water, thereby promoting water 

conservation in the Lower Basin (DOI, 2007). The ICS mechanism allows for conserved water in 

the Lower Basin to be stored in Lake Mead for subsequent delivery in future years. 

Several options suggested continuation of this program beyond the expiration of the 2007 

Interim Guidelines in 2026 and the expansion or modification to include participants beyond 

entitlement holders to Colorado River mainstem water in the Lower Basin, including Mexico4. 

These options also suggested adjustments to the rules guiding the creation and delivery of ICS 

such that certain participants may utilize the program to provide beneficial flow past Morelos 

Dam to the limitrophe reach as well as to provide other benefits within Mexico. Expansion of the 

ICS program for these purposes would require consultation with Mexico and is outside the scope 

of the Study. 

5.10.5 Groundwater Banking

This concept utilizes groundwater recharge and recovery as an underground water bank. An 

entity could divert water to groundwater storage when there is a surplus or reduced need for 

surface supplies. When there is a critical or increased need for additional supply, the entity could 

then withdraw an amount of water equivalent to that it previously banked subject to withdrawal 

limits. This concept is already used in several areas of the Lower Basin and is done so on an 

interstate basis in accordance with Title 43, Code of Federal Regulations, Part 414, Off-Stream 

Storage of Colorado River Water and Development and Release of Intentionally Created Unused 

Apportionment in the Lower Division States. 

 

4 Minute 319 was adopted by the United States and Mexico on November 20, 2012. There was not sufficient time to incorporate operational 

changes associated with Minute 319 prior to publication of this report. A copy of the Minute is available at: 

http://www.ibwc.state.gov/Files/Minutes/Minute_319.pdf. 
Technical Report F — Development

of Options and Strategies

December 2012 F-61

Groundwater banking offers two primary benefits over existing surface storage: (1) storage in 

groundwater aquifers will reduce evaporation compared to surface water storage, and (2) to 

provide additional storage capacity when surface storage facilities are full. Without further study 

of specific aquifer locations available, it is difficult to quantify the potential yield. The option is 

conceptually similar to either of the Upper Basin or Lower Basin banks and will have many of 

the same implementation challenges. Also, even though groundwater storage eliminates 

evaporation losses, other possible losses come into play, such as stranded water in the vadose 

zone, reduced water quality, and/or migration away from wells that can recapture the water.

Additionally, availability of surplus water is based on uncertain, multi-annual, wet Colorado 

River conditions. In spite of these uncertainties, groundwater banking does have the potential to 

increase yield, but was not quantified directly in the Study. 

Groundwater banking projects using infiltration basins would require extensive acquisition of 

lands if injection wells are not utilized. They also require construction of well fields to extract 

groundwater, pipelines, and power supplies. Due to the large investment and significant amount 

of impacted lands, extensive feasibility studies, permitting, and environmental assessments 

would be required. The cost for infiltration basins, wells, pipelines, pump stations, power lines, 

land acquisition, and mitigation must be balanced against increased yield, which could be highly 

variable from year to year based on the amount and frequency of recharge. It is also worth noting 

that groundwater storage has minimal evaporation losses compared to reservoir storage, but can 

have losses due to groundwater movement and groundwater stranded in the vadose zone. Both of 

these losses are difficult to quantify, but are important in selecting preferences of groundwater 

storage over surface water storage. Rough estimates considering evaporation benefits in addition 

to potential increased yield due to underground storage range from approximately $1,500 to 

$2,500 per af. 

5.11 Water Management and Allocation 

Options were submitted that suggested modifications to Basin water management processes and 

changes in the distribution of water supply available in the Basin under the Law of the River. 

The four representative options in this group are: changes to apportionment of water supply, 

processes for expanded stakeholder involvement, population control, and conservation and trust 

funds. 

5.11.1 Changes to Apportionment of Water Supply

Options were received that suggested changes in the distribution of the Basin water supply under 

the Law of the River. These submissions acknowledged that the Colorado River was apportioned 

during a particularly wet period and utilized a short period of record for recorded streamflows. 

Given that there is now a longer period of record, which indicates the average natural streamflow 

is less than records available at the time of the Compact, the submissions suggested that water be 

reallocated based on updated assumptions on the amount of water supply available on average, 

and that more water be allocated to protect critical habitat. 

Several options proposed a voluntary demand cap on the Upper Basin. These options proposed 

a negotiated agreement between the Upper and Lower Basin, in which the Upper Basin would 

agree to forebear annual consumption of Colorado River water above some specified amount 

and the Lower Basin would agree to relax the stipulation in Article III(d) of the Compact that 

the Upper Division States will not cause the flow of the river at the Lee Ferry Compact Point 

to be depleted below an aggregate of 75 maf for any period of 10 consecutive years. As 
Colorado River Basin

Water Supply and Demand Study

F-62 December 2012

described in the options submitted, the primary purpose of the mutual forbearance 

arrangement would be to provide additional water supply reliability to users in both the 

Upper and Lower Basin. The Lower Basin would obtain additional security in the Upper 

Basin’s ability to not cause the flow at Lee Ferry to be depleted as specified in Article III(d), 

and the Upper Basin would obtain additional insurance against those provisions. 

Another submission suggested creating a Colorado River Authority that uses eminent domain to 

reallocate water from farmers and others for urban purposes. 

Due to the political and legal complexity of these options, they were not considered further. 

Appendix F2 contains the options as they were submitted, and, in some cases, provide additional 

information. 

5.11.2 Process for Expanded Stakeholder Involvement

Options were submitted that suggested the establishment of a forum to allow tribes and 

stakeholders the opportunity to formally provide input into the Colorado River decision-making 

process and to discuss long-term, Basin-scale solutions to water supply and management 

challenges.

One option suggested that a wide range of stakeholders, including environmental groups, tribes, 

rural farm communities and others, meet regularly to discuss ongoing issues and proposals, to 

develop proposals related to water management, and to provide input to the Basin States and 

Reclamation, as appropriate. This group’s recommendations would be advisory in nature. 

Another option recommended the creation of a Blue Ribbon Committee composed of 

independent scientists, non-governmental organizations, tribal representatives, businesses, and 

other interests to recommend a vision for future water use in the Basin. The committee would 

develop a plan that helps to meet future water needs and restores a healthy Colorado River 

system. 

Reclamation and the Basin States acknowledge that the future of the Colorado River system is 

critical to the livelihood of the millions of people who reside in the Basin and the multiple uses 

that are dependent on the water. Interest in the Study has been broad and has included active 

participation from tribes with rights or claims to Colorado River or tributary water, agricultural 

users, purveyors of M&I water, power users and providers, recreational groups, and conservation 

organizations. It is important that input and participation by this broad range of stakeholders 

continue in order to successfully manage the Basin and confront the challenges that lie ahead if 

projected future supply and demand imbalances are realized. 

5.11.3 Population Control

This group of options suggested that measures be taken to slow, or even halt, economic and 

population growth in the Basin. Some options in this group suggest that the Southwest will 

naturally become a less desirable place to live in the next 20 to 30 years due to high 

temperatures, high energy costs, insecure water supply, and stagnant job growth. Others suggest 

the federal government should create incentives for business and industry to locate outside the 

Southwest to regions where water and energy supplies are less strained. 

Developing strategies for constraining population growth has significant political and legal 

challenges, is beyond the objectives of the Study, and was therefore not considered further. 
Technical Report F — Development

of Options and Strategies

December 2012 F-63

5.11.4 Conservation and Trust Funds

This group of options suggested the establishment of conservation funds, trusts, and other 

funding mechanisms for local and Basin-wide environmental enhancement and water 

improvement projects. Some suggestions were more local in scope, including using conservation 

on a utility-scale level to support local and regional environmental enhancement, or suggesting 

that water agencies draft resolutions calling for a fiscal requirement on new growth to fund local 

water improvement projects. One option suggested a Basin-wide trust fund, in which funds 

raised from municipal water users, recreationists, and hydropower could be used for climate 

change adaptation, environmental enhancement, and a variety of water efficiency programs. 

These options represent mechanisms that could be used to implement other options noted above, 

such as water transfers or M&I or agricultural water conservation. 

Finding ways to fund desired improvements is a critical component that can make the difference 

between a theoretical idea and an implementable solution. Reclamation offers opportunities to 

partner with private and public partners to leverage resources for ecosystem and economic 

benefits. 

Examples of such partnerships include grants provided through Reclamation’s WaterSMART 

(Sustain and Manage America's Resources for Tomorrow) program. WaterSMART works with 

states, tribes, local governments, and non-governmental organizations to secure and stretch water 

supplies for use by existing and future generations to benefit people, the economy, and the 

environment, and to identify adaptive measures needed to address climate change and future 

demands5. Grants through the WaterSMART program provide 50-50 percent cost-shared funding 

for a variety of projects, including water efficiency, conservation, and Public Law 102-575, 

Title XVI water reclamation and reuse projects6. 

Because it lacks the authority to establish a Basin-wide fund in which additional fees are levied 

on water use, Reclamation encourages local water agencies to develop innovative ways of 

funding conservation and local water improvement projects. The WaterSMART program is an 

example of a Reclamation program that could be used as a model for collaborative cost share 

funding to assist financially with water supply and ecosystem improvements

5.12 Tribal Water 

Tribes hold quantified rights to a significant amount of water from the Colorado River and its 

tributaries (approximately 2.9 maf of annual diversion rights). The term “quantified rights”, as 

used in the context of the Study, is defined as the quantity of water rights reserved by or granted 

to tribes by federal court decrees, state court decrees, treaties, agreements, and Executive Orders. 

In many cases, these rights are senior to other users. Reclamation and the Basin States 

acknowledge that tribes are critical partners in current and future efforts to resolve water supply 

and demand imbalances.

Options pertaining to water development and use were submitted by tribes for consideration in 

the Study. The submitted concepts do not lend themselves to characterization criteria ratings and 

modeling through CRSS; however, they raise important issues that deserve and will receive 

 

5 From: DOI WaterSMART Strategic Implementation Plan March 22, 2011: 

http://www.usbr.gov/WaterSMART/docs/FedRegister_WaterSMART_Implementation_plan_FINAL.PDF. 

6 Information on projects funded through the WaterSMART program as well as the current status on WaterSMART funding is available at: 

http://www.usbr.gov/WaterSMART/grants.html. 
Colorado River Basin

Water Supply and Demand Study

F-64 December 2012

future discussion and further study, where appropriate (see Study Report – Future 

Considerations and Next Steps). The options submitted by tribes are summarized in the sections 

below and every effort was made to retain the original intent. Appendix F13 contains the 

submittals of the Ten Tribes Partnership and Inter Tribal Council of Arizona (ITCA) in their 

entirety. Options submitted by individual tribes can be found in appendix F2. 

5.12.1 Voluntary Tribal Water Transfers 

Options were submitted by the tribes, recognizing the role of tribal water rights and in particular, 

the possibility of voluntary transfer of that water, in helping to resolve future supply and demand 

imbalances. The suggested water transfer mechanisms included, among other suggestions, water 

banks, water marketing, forbearance, and intra- and interstate/Basin leases. The basic concept is 

that undeveloped portions of tribal water entitlements could be voluntarily made available to 

other users in (or in some cases beyond) the hydrologic boundaries of the Basin for an agreedupon level of compensation. These voluntary transfers could be renewed or revisited annually or 

could be in place for a longer specified amount of time depending on the agreed-upon terms of 

the transfer. 

5.12.2 Tribal Water Storage and Intentionally Created Surplus 

The Ute Indian Tribe of the Uintah and Ouray Reservation and the ITCA requested that 

consideration be given to storing tribal water in new or existing reservoirs for improved 

irrigation, community and economic development, or conversion to year-round use. These 

options were designed to help enable tribes with rights to water to beneficially use all of the 

water to which they have rights. Tribes in the Lower Basin suggested an incentive program be 

developed to encourage conservation of tribal waters. Specifically, a demonstration program 

titled Tribal Conservation Reserve was suggested, in which tribes are eligible to store a specified 

amount of water in Lake Mead in the form of a reserve and then divert that water in a future year 

by calling on its credits. This option also suggested that agricultural drainage water be stored and 

put to beneficial reuse use on tribal lands. 

5.12.3 Inter-governmental Forum

The Ten Tribes Partnership and the ITCA suggested that additional study, led by tribes and the 

federal government, be conducted to better understand the role of tribal water in the Basin. It is 

anticipated that the additional study would require involvement of the states and could support an 

inter-governmental forum to discuss and resolve current and future issues affecting the 

management of the Colorado River. 

5.12.4 Resolution of Tribal Claims 

The ITCA believes that resolution of tribal water claims must be a major priority and it requested 

that DOI take all necessary steps to facilitate the settlement of claims that have yet to be 

quantified. It was suggested that Reclamation and the affected tribes work together to develop a 

water acquisition strategy and implementation plan to provide water to satisfy currently 

unquantified tribal rights. 

5.12.5 Affordability of Tribal Waters via Central Arizona Project Canal 

Tribes have expressed concern regarding increased costs of Central Arizona Project (CAP) water 

to which tribes located in central Arizona have rights. Additionally, these concerns state that 
Technical Report F — Development

of Options and Strategies

December 2012 F-65

federal policy on Colorado River water must ensure that CAP water in all tribal settlements is 

affordable. 

5.12.6 Barriers to Tribal Participation in Federal Programs

The ITCA noted that water conservation and increases in the efficiency of agricultural, 

municipal, and other water use in reservation areas are high priority issues for all tribes. With a 

limited tax base, lack of funding is a serious obstacle for tribes. Tribal governments need to draw 

on a variety of federal programs to provide that funding. Barriers to tribal participation include: 

requirements for explicit waivers of sovereign immunity, cost-sharing requirements with limited 

or no possibility of exceptions for communities with the most severe need and least ability to 

pay. 

5.12.7 Recognition of Limits

The ITCA believes that all communities must respect limits to the quantity of water in the 

system, not just tribal communities. Future population growth and economic development in the 

non-Indian communities of the Basin must be conditioned by the federal, state, and local 

governments on the availability and sustainability of the water resources necessary to support 

such growth and development. 

5.12.8 Stabilization of Soil

The ITCA suggested that streamflow in the Colorado River may be augmented through a soil 

stabilization program on the Navajo reservation and nearby lands at Hopi. 

5.12.9 Non-Tributary Groundwater Use 

The Ute Indian Tribe of the Uintah and Ouray Reservation requested that it be allowed to engage 

in new tribal development of groundwater that is not hydrologically connected to surface waters 

in the Basin and that groundwater that is not hydrologically connected should not be deducted 

from Utah’s Colorado River allocation. Development of such sources may augment supplies and 

alter demands in the Upper Colorado River Basin. 

5.12.10 Protection Against Overallocation

The Ute Indian Tribe of the Uintah and Ouray Reservation suggested that the State of Utah and 

the tribe should protect against overallocation by entering into agreements for any non-tribal 

water use allocated from the tribe’s reserved quantity. 

5.13 Data and Information 

Options were submitted that suggested improvements to data and information used by 

Reclamation for analysis and modeling. There are two representative options in this group, 

summarized below. 

5.13.1 Colorado River Simulation System Modeling Improvements

One option suggested the incorporation of additional “nodes” in CRSS that correspond to 

USGS streamflow gaging stations. The primary goal of this suggestion was to allow Reclamation 

to better model impacts to recreational and ecological resources at a finer spatial scale. 

Currently, there are 29 USGS streamflow gaging stations (20 in the Upper Basin upstream of and 

including the Lees Ferry gaging station in Arizona, and 9 below Lees Ferry including the Paria 

River and inflow points in the Lower Basin) represented in CRSS as nodes at which natural flow 
Colorado River Basin

Water Supply and Demand Study

F-66 December 2012

is input. Natural flow represents the flow that would have occurred at the location had depletions 

and reservoir regulation not been present upstream of that location. 

The addition of “nodes” that correspond to USGS streamflow gaging stations would first require 

the computation of natural flow at that location. The computation of natural flow, performed in 

Reclamation’s Natural Flow model, requires fine resolution data for gaged flows, reach gains 

and losses, diversions, depletions, and return flows. There are inherent challenges to adding flow 

nodes to the model because much of the fine resolution data required are not available. For 

example, USGS gages have varying record lengths at various locations. In addition, water use 

information may not presently be available at the required resolution, or it may be determined 

through differing methodologies across different geographic areas. These inconsistencies and 

unavailability of data, combined with record length, pose significant challenges to the 

development of a Basin-wide higher resolution natural flow model to provide the data needed to 

run CRSS. 

Although there are limitations in spatial and temporal (CRSS is at a monthly time step) 

resolution in CRSS, the Study has utilized alternative methods of evaluating impacts to 

recreation. There are many different recreational activities that are supported by rivers and 

streams throughout the Basin. River and whitewater boating were considered an attribute of 

interest in the Study. River and whitewater boating experiences vary with flow conditions, as 

well as other non-flow-related factors. For the Study, American Whitewater developed 

relationships between flow conditions and the quality of the boating experience by applying 

methodology developed by Whittaker et al., 2005. The method takes monthly values from CRSS 

and, based on historical data, estimates daily flows. These values are then compared against 

survey data to determine how many days in that month would have provided optimal, acceptable, 

or unacceptable whitewater and boating recreation. This methodology is described in detail in 

Technical Report D – System Reliability Metrics, Appendix D2 – Boating Flow Days Metrics. 

Reclamation is committed to working with partners and stakeholders to refine CRSS and other 

supporting models where it is feasible and useful to provide the most realistic representation of 

how the system is currently operated and how it will likely be operated in the future. 

5.13.2 Improved Water Use Accounting in the Upper Basin

Improvements to Upper Basin water use accounting methods were suggested. Specifically, the 

suggestions advocated for the Upper Basin to agree to common standards for water use 

accounting, which in turn would be implemented via programs of each state. These standards 

may result in timely annual reporting of consumptive use and losses, and would encourage 

adoption of appropriate technologies (for example, metering or remote sensing).

In 1968, the Colorado River Basin Project Act directed the Secretary of the Interior to 

make reports as to the annual consumptive uses and losses of water from the 

Colorado River system after each successive five-year period starting on October 

1, 1970. Such reports shall include a detailed breakdown of the beneficial 

consumptive use of water on a State-by-State basis. Specific figures on quantities 

consumptively used from the major tributary streams flowing into the Colorado 

River shall also be included on a State-by-State basis. Such reports shall be 

prepared in consultation with the States of the lower basin individually and with 

the Upper Colorado River Commission, and shall be transmitted to the President, 
Technical Report F — Development

of Options and Strategies

December 2012 F-67

the Congress, and to the Governors of each State signatory to the Colorado River 

Compact...

These reports (the Colorado River System Consumptive Uses and Losses Reports7), have been 

prepared by Reclamation, in collaboration with the Basin States, for every 5-year period from 

1971 through 2005. To date, the report covering 2001 through 2005 is in final review and a 

provisional report covering the period 2006 through 2008 has been prepared. 

Reclamation, independent of the Study, is collaborating with the Upper Colorado River 

Commission and the Upper Basin to develop more-timely and standardized methods of reporting 

for Upper Basin consumptive uses and losses. This effort entails exploring the numerous 

methodologies that are currently available for computing consumptive uses and losses, and 

evaluating the strengths and weaknesses of these methodologies. The evaluation will include 

both technical considerations and constraints that contribute to the method’s potential utility on 

an operational basis. Once the catalog of methodologies is complete, the appropriateness of the 

use of a single methodology or a set of methodologies for the computation of consumptive uses 

and losses will be discussed. 

5.14 Characterization Summary 

Table F-8 summarizes the potential yield for each of the main option groups in 2035 and 2060. A 

total of 7.6 mafy of potential yield was identified for options that increase supply. The options 

with greatest yield of this type are related to watershed management methods, desalination of 

ocean and brackish water, importation, and reuse. A total of 2.2 mafy of potential savings was 

identified through options that reduce demand. The principal options that comprise this type are 

agricultural water conservation, M&I water conservation, and energy water use efficiency. 

Potential savings totaling 1.2 mafy were identified under the options that modify system 

operations and primarily reflect reducing reservoir or canal evaporation through physical or 

chemical covers, or through preferential reservoir storage. When considering all options and all 

categories by 2060, a total of more than 11 mafy in potential yield was identified. The potential 

yield is approximately 5.7 mafy by 2035. However, not all options are equally feasible or reliable 

in the long term. Likewise, some of these options are mutually exclusive. Many options, such as 

imports to Southern California or watershed management, are uncertain from both a technical 

feasibility and reliability standpoint. By excluding options that were rated low for these factors 

(“D” and “E”), the total potential yield is reduced to approximately 3.7 mafy by 2035 and to 

approximately 7 mafy by 2060. 

The cost, yield, and timing of the representative options are shown in figure F-12 (sorted based 

on cost). Some of the least-cost options are related to weather modification and chemical covers, 

but these have considerable uncertainty related to their long-term viability and implementation

risk. Agricultural water conservation, M&I water conservation, watershed management methods, 

smaller import options, and brackish water desalination projects represent the next-leastexpensive set of options. Seawater desalination, reuse, and importation projects are estimated to 

have higher costs, but still can have substantially lower costs than distributed rainwater 

harvesting and grey water reuse options, and canal and reservoir covers. 

 

7 Available at: http://www.usbr.gov/uc/library/envdocs/reports/crs/crsul.html.
Colorado River Basin

Water Supply and Demand Study

F-68 December 2012

6.0 Development of Portfolios 

Based on the results of the characterization and development of representative options, various 

options have been combined into portfolios representing different potential adaptation strategies. 

The Study developed four exploratory portfolios to reflect different strategies for selecting and 

combining options to address Colorado River imbalances between water supply and water 

demand. Each portfolio consists of a unique selection of options that were considered to address 

vulnerabilities (e.g., declining Lake Mead pool elevation) that may exist under future 

combinations of supply and demand. The portfolios were implemented dynamically in CRSS, 

TABLE F-8 

Summary of Option Cost and Potential Yields by 2035 and 2060

Option 

Category Option Group

Estimated 

Cost

($/afy)

Years 

before 

Available

Potential 

Yield by 

2035

(afy)

Potential 

Yield by 

2060 

(afy)

Importation Imports to the Colorado Front 

Range from the Missouri or 

Mississippi Rivers

1,700–2,300 30 0 600,000

Imports to the Green River from 

the Bear, Snake, or Yellowstone 

Rivers

700–1900 15 158,000 158,000

Imports to Southern California via 

Icebergs, Water Bags, Tankers, or 

the Columbia River

2,700–3,400 15 600,000 600,000

Subtotal 758,000 1,358,000

Desalination Gulf of California 2,100 20–30 200,000 1,200,000

Pacific Ocean in California 1,850–2,100 20–25 200,000 600,000

Pacific Ocean in Mexico 1,500 15 56,000 56,000

Salton Sea Drainwater 1,000 15–25 200,000 500,000

Groundwater in Southern 

California

750 10 20,000 20,000

Groundwater in the Area near 

Yuma, Arizona

600 10 100,000 100,000

Subtotal 776,000 2,476,000

Reuse Municipal Wastewater 1,500–1,800 10–35 200,000 932,000

Grey Water 4,200 10 178,000 178,000

Industrial Wastewater 2,000 10 40,000 40,000

Subtotal 418,000 1,150,000

Local Supply Treatment of CBM -Produced 

Water

2,000 10 100,000 100,000

Rainwater Harvesting 3,150 5 75,000 75,000

Subtotal 175,000 175,000
Technical Report F — Development

of Options and Strategies

December 2012 F-69

TABLE F-8 

Summary of Option Cost and Potential Yields by 2035 and 2060

Option 

Category Option Group

Estimated 

Cost

($/afy)

Years 

before 

Available

Potential 

Yield by 

2035

(afy)

Potential 

Yield by 

2060 

(afy)

Watershed 

Management

Brush Control 7,500 15 50,000 50,000

Dust Control 220–520 15–25 280,000 400,000

Forest Management 500 20–30 200,000 300,000

Tamarisk Control 400 15 30,000 30,000

Weather Modification 30–60 5–45 700,000 1,700,000

Subtotal 1,260,000 2,480,000

M&I Water 

Conservation

M&I Water Conservation 500–900 5–40 600,000 1,000,000

Subtotal 600,000 1,000,000

Agricultural 

Water 

Conservation

Agricultural Water Conservation 150–750 10–15 1,000,000 1,000,000

Agricultural Water Conservation 

with Transfers 

250–750 5–15 1,000,000 1,000,000

Subtotal 1,000,0001 1,000,0001

Energy Water 

Use Efficiency

Power Plant Conversion to Air 

Cooling

2,000 10 160,000 160,000

Subtotal 160,000 160,000

System 

Operations

Evaporation Control via Canal 

Covers

15,000 10 18,000 18,000

Evaporation Control via Reservoir 

Covers

15,000 18 200,000 200,000

Evaporation Control via Chemical 

Covers on Canals and Reservoirs

100 15–25 200,000 850,000

Construction of New Storage 2,250 15 20,000 20,000

Improved Groundwater 

Management

N/A N/A N/A N/A

Modified Reservoir Operations unknown 15 0-300,000 0-300,000

Subtotal 588,000 1,238,000

Total of All Options 5,735,0002 11,037,0002

1 The two agricultural water conservation representative options derive potential yield from similar measures and are 

thus not additive 2 Total does not account for several options that may be mutually exclusive due to regional integration limitations or 

are dependent on the same supply
Colorado River Basin 

Water Supply and Demand Study

F-70 December 2012

FIGURE F-12

Summary of Options Characterization Ratings (aggregated by option groups)

Technical Environmental Social Other
Technical Report F — Development

of Options and Strategies

December 2012 F-71

meaning options were implemented based on the portfolio strategy depending on the timing and 

nature of the vulnerabilities. Portfolios were then analyzed to assess the effects of the strategy on 

resolving vulnerabilities to Basin resources.

The four distinct strategies and dynamic portfolios represent a range of reasonable but different 

approaches for resolving future supply and demand imbalances (figure F-13). The portfolios 

were developed by the Options and Strategies Sub-Team and are meant to be exploratory in 

nature. The portfolios are not intended to represent all possible strategies for grouping options. 

Further, the Study did not intend to result in the selection of a particular portfolio or any one 

option from any portfolio. Rather, the objective of the portfolio analysis was to demonstrate the 

effectiveness of different strategies at resolving future supply and demand imbalances. 

Using the ratings associated with the criteria, preferences were expressed that resulted in two 

portfolios, Portfolio B and Portfolio C. Two other portfolios were then added, Portfolio A which 

represents a highly inclusive strategy (includes all options in either Portfolio B or Portfolio C) 

and Portfolio D, which represents a highly selective strategy (includes only options in both 

Portfolio B and Portfolio C). Portfolio B includes options with high technical feasibility and 

long-term reliability, but excludes options with the highest permitting, legal, policy, or long-term 

viability risks. Portfolio B also excludes any options that cost more than $2,500 per af. Portfolio 

C focuses on options that are also highly feasible, but excludes options that could have greater 

environmental impacts. This portfolio excludes options that cost more than $4,200 per af. The 

schematic in figure 13 shows the relationships of the options included in the Study portfolios. 

FIGURE F-13

Relationships between Options in the Four Study Portfolios
Colorado River Basin

Water Supply and Demand Study

F-72 December 2012

6.1 Defining Portfolios and Option Preferences 

Information about the options characteristics, including expected yield, cost, available timing, 

and 14 other attributes, such as technical feasibility, operational flexibility, and energy needs 

(table F-9) was used to help define portfolios. These portfolios reflect an initial look at option 

performance based on different strategies for resolving imbalances. Additional analysis to fully 

define appropriate options will be required as future conditions evolve. 

TABLE F-9 

Option Criteria and Categories Utilized in the Development of Portfolios

Technical Environmental

Technical Feasibility

Implementation Risks

Long-Term Viability 

Operational Flexibility

Permitting 

Energy Needs

Energy Source

Other Environmental Factors

Social Other

Recreation

Policy

Legal

Socioeconomics

Quantity of Yield

Cost

Timing

Hydropower

Water Quality

In developing each unique portfolio, a set of preferences regarding the characteristics of options, 

as defined by the criteria ratings, was defined. These preferences reflect the particular strategy of 

the portfolio. The options were then arranged with the desired criteria ratings by cost 

effectiveness – a measure of the cost per unit yield. The availability of each option is restricted to 

be no earlier than the first year identified under the “timing” criterion. As more restrictions are 

placed on the range of option characteristics, the number of options and potential yield included 

in the portfolio are reduced. 

The Options and Strategies Sub-Team assisted in the development of the four portfolios by 

suggesting general strategies, option criteria preference sets, and reviewing draft portfolios. The 

option criteria preferences included in each portfolio are listed in table F-10. In general, Portfolio 

A contains the fewest restrictions on option preferences and therefore includes the largest number 

and broadest set of options. Conversely, Portfolio D contains the most restrictions on option 

preferences and therefore includes the fewest options. Portfolio B and Portfolio C reflect 

different strategies for addressing the long-term projected imbalances and include a modest range 

of options. Adjustments to portfolios were made to either include or exclude specific options or 

to specify that an option is to be implemented as soon as it is available based on input from the 

Options and Strategies Sub-Team members. 

The following sections describe each exploratory portfolio in greater detail. 
Technical Report F — Development

of Options and Strategies

December 2012 F-73

TABLE F-10

Option Criteria Preferences for the Four Portfolios

Criteria 

Category Option Criteria

Portfolio 

Portfolio A Portfolio B Portfolio C Portfolio D

Technical Technical 

Feasibility

excludes 

options rated 

D & E

excludes 

options rated 

D & E

excludes 

options rated 

D & E

excludes options 

rated D & E

Implementation 

Risk

all all all all

Long-term 

Viability

excludes 

options rated E 

excludes 

options rated D 

& E

excludes 

options rated E 

excludes options 

rated D & E

Operational 

Flexibility

all all all all

Environmental Permitting excludes 

options rated E 

excludes 

options rated E 

excludes 

options rated 

D & E

excludes options 

rated D & E

Energy Needs all all excludes 

options rated 

D & E

excludes options 

rated D & E

Energy Source all all excludes 

options rated E 

excludes options 

rated E 

Other 

Environmental 

Impacts

all all excludes 

options rated 

D & E

excludes options 

rated D & E

Social Recreation all all excludes 

options rated 

D & E

excludes options 

rated D & E

Legal excludes 

options rated E 

excludes 

options rated E 

excludes 

options rated E 

excludes options 

rated E 

Policy excludes 

options rated E 

excludes 

options rated E 

excludes 

options rated E 

excludes options 

rated E 

Socioeconomics all all all all

Other Hydropower all all all all

Water Quality all all all all

Cost < $4,200 per af < $2,500 per af < $4,200 per af < $2,500 per af

Portfolio A and Portfolio C also include the following options: Upper Basin Water Bank, Watershed-Dust (Step 2), 

Desal-Salton Sea (Steps 2 and 3), Reuse-Municipal (steps 3-5), and Desal-Yuma. Portfolio D also includes the 

following options: Desal-Salton Sea (Steps 2 and 3), Reuse-Municipal (Steps 3-5), and Desal-Yuma. Portfolio C and 

Portfolio D exclude the following option: Local-CBM. 

6.2 Portfolio A 

Portfolio A features options that are included in both Portfolio B and Portfolio B. Implementing 

all options in this portfolio when available would yield on average about 6.3 maf of new supply 

or reduced demand. In the full implementation of this portfolio, about 4.1 mafy of options that 

increase supply are included, and about 2.2 mafy of options that reduce demand are included. 

This portfolio also includes the Upper Basin water bank concept described in Portfolio C. 
Colorado River Basin

Water Supply and Demand Study

F-74 December 2012

Figure F-14 indicates the options included in the portfolio and their relative cost, yield, and 

timing availability. Table F-11 summarizes the portfolio of options by option category and yield 

in the near term and long term as well as whether the option is always on or is triggered by 

system conditions (responds to signposts). 

FIGURE F-14

Ordered Options, Yield, Cost, and Timing Availability for Portfolio A
Technical Report F — Development

of Options and Strategies

December 2012 F-75

TABLE F-11 

Summary of Included Options for Portfolio A

Near-Term1 Long-Term2 Total

Option 

Category Option Type

Number of 

Options

Sum of 

Yield (afy) 

Number of 

Options

Sum of 

Yield (afy) 

Number of 

Options

Sum of 

Yield (afy) 

Augment 

Supply

Desal 8 1,176 2 300 10 1,476

Import 0 0 1 600 1 600

Local Supply 2 175 0 2 175

Reuse 4 618 3 532 7 1,150

Watershed 

Management 4 610 1 120 5 730

Total 18 2,579 7 1,552 25 4,131

Reduce 

Demand

Agricultural 

Conservation 5 1,000 0 0 5 1,000

Energy Water 

Use Efficiency 1 160 0 0 1 160

M & I 

Conservation 3 600 2 400 5 1,000

Total 9 1,760 2 400 11 2,160

Grand Total 27 4,339 9 1,952 36 6,291

1 Near-Term refers to options that can be implemented before 2035. 

2 Long-Term refers to options that are implemented after 2035. 

To demonstrate the yield and cost of options over time included in Portfolio A, figure F-15 

shows the total portfolio yield over time for several different portfolio average costs. The top line 

shows the yield reaching the maximum amount of 5.1 mafy in 2052 with an average portfolio 

cost of around $1,000 per af. If the implementation of this portfolio only required roughly 

3.0 mafy by 2050, then the average cost of the portfolio would be closer to $500 per af. Because 

the portfolio is described as a preference of options that are then ordered by cost effectiveness, 

each subsequent option that is called for in a portfolio reflects an increasing cost.
Colorado River Basin

Water Supply and Demand Study

F-76 December 2012

FIGURE F-15

Total Portfolio Yield over Time by Average Cost for Portfolio A

6.3 Portfolio B 

Portfolio B is based on a strategy that seeks long-term water supply reliability through 

implementation of options with high technical feasibility and long-term reliability. The strategy 

can be defined as one that seeks options with proven technology and that, once in place, will 

produce reliable long-term yield. The strategy represents a low-risk strategy in the long term, but 

may consider greater risk with respect to permitting and implementation. However, this portfolio 

excludes options with the highest permitting, legal, and policy risks, or ones that are estimated to 

cost more than $2,500 per af (table F-10). The portfolio includes a blend of options that increase 

supply and those that decrease demand. Water conservation and a variety of desalination options 

are included in the near-term (first 25 years), and imports and expansion of reuse programs 

dominate the longer-term options. If all 31 options in this portfolio were implemented when 

available, the total system yield in the near term would increase by about 3.8 maf and by the end 

of the Study period (2060) would increase by about 5.6 maf. Figure F-16 indicates the options 

included in the portfolio and their relative cost, yield, and timing availability. Table F-12 

summarizes the portfolio of options by option category and yield in the near term and long term. 
Technical Report F — Development

of Options and Strategies

December 2012 F-77

FIGURE F-16 

Ordered Options, Yield, Cost, and Time Availability for Portfolio B
Colorado River Basin

Water Supply and Demand Study

F-78 December 2012

TABLE F-12

Summary of Included Options for Portfolio B

Near-Term1 Long-Term2 Total

Option 

Category Option Type

Number of 

Options

Sum of 

Yield 

(kafy) 

Number of 

Options

Sum of 

Yield 

(kafy) 

Number of 

Options

Sum of 

Yield (kafy) 

Increase 

Supply

Desal 8 1,176 2 300 10 1,476

Import 0 0 1 600 1 600

Local Supply 1 100 0 0 1 100

Reuse 3 440 3 532 6 972

Watershed 

Management 2 300 0 0 2 300

Total 14 2,016 6 1,432 20 3,448

Reduce 

Demand

Agricultural 

Conservation 5 1,000 0 0 5 1,000

Energy Water 

Use Efficiency 1 160 0 0 1 160

M & I 

Conservation 3 600 2 400 5 1,000

Total 9 1,760 2 400 11 2,160

Grand Total 23 3,776 8 1,832 31 5,608

1 Near-Term refers to options that can be implemented before 2035. 

2 Long-Term refers to options that are implemented after 2035. 

To demonstrate the yield and cost of options over time included in Portfolio B, figure F-17 

shows the total portfolio yield over time for several different portfolio average costs. The top line 

shows the yield reaching the maximum amount of 4.4 mafy in 2052 with an average portfolio 

cost of around $1,000 per af (annualized). If the implementation of this portfolio only required 

roughly 3.0 mafy by 2050, then the average cost of the portfolio would be closer to $750 per af. 

Because the portfolio is described as a preference of options that are then ordered by cost 

effectiveness, each subsequent option that is called for in a portfolio reflects an increasing cost.
Technical Report F — Development

of Options and Strategies

December 2012 F-79

FIGURE F-17 

Total Portfolio/ Yield over Time by Average Cost for Portfolio B 

6.4 Portfolio C 

Portfolio C focuses on options that are technically feasible but also have low environmental 

impacts—low energy needs, lower carbon energy sources, easier permitting, and low impacts to 

other environmental resources. This portfolio also avoids options that are potentially unfavorable 

to recreational interests. In addition, this portfolio excludes options with the highest permitting, 

legal, and policy risks, or ones that have an annualized cost of more than $4,200 per af. If all 

29 options in this portfolio were implemented when available, total system yield in the near term 

(year 25) would increase by about 3.6 maf and by 2060 would increase by about 4.7 maf. The 

portfolio includes significant conservation in the near term and relies on reuse and watershed 

management rather than desalination and imports to augment supplies in the longer term. In 

addition to options that either reduce demand or increase supply, the portfolio also includes a 

mechanism to transfer water conserved in the Upper Basin through M&I and agricultural water 

conservation, and energy water use efficiency, to a conceptual Upper Basin water bank. Water is 

stored in the water bank until needed to be released in order to avoid Upper Basin curtailment 

due to Compact obligations. 

Figure F-18 indicates the options included in the portfolio and their relative cost, yield, and 

timing availability. Table F-13 summarizes the portfolio of options by option category and yield 

in the near term and long term. 
Colorado River Basin

Water Supply and Demand Study

F-80 December 2012

FIGURE F-18 

Ordered Options, Yield, Cost, and Time Availability for Portfolio C

TABLE F-13

Summary of Included Options for Portfolio C

Option 

Category Option Type

Near-Term Long-Term Total

Number of 

Options

Sum of 

Yield (afy)

Number of 

Options

Sum of 

Yield (afy)

Number of 

Options

Sum of 

Yield (afy)

Augment 

Supply

Desal 4 520 1 100 5 620

Import 0 0 0 0 0 0

Local Supply 1 75 0 0 1 75

Reuse 4 618 3 532 7 1,150

Watershed 

Management 4 610 1 120 5 730

Total 13 1,823 5 752 18 2,575

Reduce 

Demand

Agricultural 

Conservation 5 1,000 0 0 5 1,000

Energy Water 

Use Efficiency 1 160 0 0 1 160

M & I 

Conservation 3 600 2 400 5 1,000

Total 9 1,760 2 400 11 2,160

Grand Total 22 3,583 7 1,152 29 4,735

1 Near-Term refers to options that can be implemented before 2035.

2 Long-Term refers to options that are implemented after 2035.
Technical Report F — Development

of Options and Strategies

December 2012 F-81

To demonstrate the yield and cost of options over time included in Portfolio C, figure F-19 

shows the total portfolio yield over time for several different portfolio average costs. The top line 

shows the yield reaching the maximum amount of 4.7 mafy in 2052 with an average portfolio 

cost of around $1,000 per af. If the implementation of this portfolio only required roughly 

3.0 mafy by 2050, then the average cost of the portfolio would be closer to $500 per af. Because 

the portfolio is described as a preference of options that are then ordered by cost effectiveness, 

each subsequent option that is called for in a portfolio reflects an increasing cost. 

FIGURE F-19 

Total Portfolio Yield over Time by Average Cost for Portfolio C

6.5 Portfolio D 

Portfolio D includes only those options included in both Portfolio B and Portfolio C. 

Implementing all options in this portfolio when available would yield on average about 4.0 maf

of new supply or reduced demand. Significant options not included in this portfolio are several 

desalination options and imports from the Missouri River. In addition to containing less potential 

yield than other portfolios, Portfolio D includes the fewest number of options. 

Figure F-20 indicates the options included in the portfolio and their relative cost, yield, and 

timing availability. Table F-14 summarizes the portfolio of options by option category and yield 

in the near term and long term. 
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Water Supply and Demand Study

F-82 December 2012

FIGURE F-20

Ordered Options, Yield, Cost, and Timing Availability for Portfolio D

TABLE F-14

Summary of Included Options for Portfolio D

Near-Term Long-Term Total

Option 

Category Option Type

Number 

of 

Options

Sum of Yield 

(afy) 

Number 

of 

Options

Sum of Yield 

(afy) 

Number 

of 

Options

Sum of Yield 

(afy) 

Augment 

Supply

Desal 4 520 1 100 5 620

Import 0 0 0 0 0 0

Local Supply 0 0 0 0 0 0

Reuse 3 440 3 532 6 972

Watershed 

Management 2 300 0 0 2 300

Total 9 1,260 4 632 13 1,892

Reduce 

Demand

Agricultural 

Conservation 5 1,000 0 0 5 1,000

Energy Water 

Use Efficiency 1 160 0 0 1 160

M & I 

Conservation 3 600 2 400 5 1,000

Total 9 1,760 2 400 11 2,160

Grand Total 18 3,020 6 1,032 24 4,052

1 Near-Term refers to options that can be implemented before 2035.

2 Long-Term refers to options that are implemented after 2035.
Technical Report F — Development

of Options and Strategies

December 2012 F-83

To demonstrate the yield and cost of options over time included in Portfolio D, figure F-21 

shows the total portfolio yield over time for several different portfolio average costs. The top line 

shows the yield reaching the maximum amount of 5.1 mafy in 2052 with an average portfolio 

cost of around $1,000 per af. If the implementation of this portfolio only required roughly 

3.0 mafy by 2050, then the average cost of the portfolio would be closer to $500 per af. Because 

the portfolio is described as a preference of options that are then ordered by cost effectiveness, 

each subsequent option that is called for in a portfolio reflects an increasing cost. 

FIGURE F-21

Total Portfolio Yield over Time by Average Cost for Portfolio D

6.6 Portfolio Comparison

The four portfolios described above represent different exploratory approaches for addressing the 

projected imbalances between water supply and demand. These portfolios were developed in 

conjunction with the Options and Strategies Sub-Team, but should not be considered as 

individual suggestive pathways. Rather, they were developed to explore the range of options, 

different preferences for option characteristics, and different levels of option inclusion. 

Table F-15 provides a high-level comparison of the options that were either included in all 

portfolios, included in some but not all portfolios, or were not included in any portfolio. 

As can be seen in the table, the highest steps of Gulf of California and Pacific Ocean

desalination options, the most complex import options, reservoir and canal covers, and many of 

the watershed management options were not selected for inclusion in any of the portfolios. 
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Water Supply and Demand Study

F-84 December 2012

TABLE F-15

Frequency of Option Inclusion Across the Four Study Portfolios 

Option Type Included in All Portfolios 

Included in Some 

Portfolios Not Included in Any Portfolio

Conservation Ag Cons-Transfer (Step 1) 

Ag Cons-Transfer (Step 2) 

Ag Cons-Transfer (Step 3) 

Ag Cons-Transfer (Step 4) 

Ag Cons-Transfer (Step 5) 

M&I Conservation (Step 1) 

M&I Conservation (Step 2) 

M&I Conservation (Step 3) 

M&I Conservation (Step 4) 

M&I Conservation (Step 5) 

Ag Conservation (Step 1) 

Ag Conservation (Step 2) 

Ag Conservation (Step 3) 

Ag Conservation (Step 4) 

Ag Conservation (Step 5) 

Desal Desal-SoCal groundwater

Desal-Yuma

Desal-Salton Sea (Step 1) 

Desal-Salton Sea (Step 2) 

Desal-Salton Sea (Step 3) 

Desal-Pacific OceanMexico

Desal-Gulf (Step 1 

Desal-Pacific Ocean-CA 

(Step 1) 

Desal-Gulf (Step 2) 

Desal-Pacific Ocean-CA 

(Step 2) 

Desal-Gulf (Step 3) 

Desal-Gulf (Step 4) 

Desal-Gulf (Step 5) 

Desal-Gulf (Step 6) 

Desal-Pacific Ocean (Step 3) 

Energy Water 

Use Efficiency

Power Plan Conversion to 

Air Cooling

Import Import-Front RangeMissouriImport-Front Range-Mississippi

Import-SoCal-Columbia

Import-SoCal-Icebergs

Import-SoCal-Tankers (Step 1) 

Import-SoCal-Tankers (Step 2) 

Import-SoCal-Tankers (Step 3) 

Import-SoCal-Water Bags (Step 1) 

Import-SoCal-Water Bags (Step 2) 

Import-SoCal-Water Bags (Step 3) 

Local Supply Local-Rain

Local-CBM

Reuse Reuse-Industrial

Reuse-Municipal (Step 1) 

Reuse-Municipal (Step 2) 

Reuse-Municipal (Step 3) 

Reuse-Municipal (Step 4) 

Reuse-Municipal (Step 5) 

Reuse-Grey Water
Technical Report F — Development

of Options and Strategies

December 2012 F-85

TABLE F-15

Frequency of Option Inclusion Across the Four Study Portfolios 

Option Type Included in All Portfolios 

Included in Some 

Portfolios Not Included in Any Portfolio

System 

Reoperations 

SysOps-Covers-Canals

SysOps-Covers (Step 1) 

SysOps-Covers (Step 2) 

SysOps-Covers (Step 3) 

SysOps-Covers (Step 4) 

SysOps-Covers (Step 5) 

Watershed 

Management

Watershed-Weather Mod

(Step 1) 

Watershed-Weather Mod

(Step 2) 

Watershed-Tamarisk

Watershed-Dust (Step 1) 

Watershed-Dust (Step 2) 

Watershed-Brush

Watershed-Forest (Step 1) 

Watershed-Forest (Step 2) 

Watershed-Weather Mod (Step 3) 

Watershed-Weather Mod (Step 4) 

Watershed-Weather Mod (Step 5) 

Watershed-Weather Mod (Step 6) 

Watershed-Weather Mod (Step 7) 

Watershed-Weather Mod (Step 8) 

Watershed-Weather Mod (Step 9) 

Water Banking Upper Basin Water Bank

However, only 12 options are included in some but not all portfolios. These included ocean 

desalination options, imports from the Missouri River, expensive options related to local 

distributed supply or reuse development such as rainwater harvesting and grey water reuse, and 

watershed management options such as tamarisk control and dust management. 

The differences in the selection or inclusion of options in the portfolios also influences the total 

potential yield and implementation cost. Figure F-22 shows the potential yield of the four 

portfolios over time for three different limits on the portfolio average cost. On the right, the 

portfolios are essentially unconstrained by cost (average costs are less than $1,250 per af). Not 

surprisingly, Portfolio A has the highest potential yield (~6.3 maf) and Portfolio D has the lowest 

potential yield (~4.0 maf). Portfolio B and Portfolio C yields are similar through 2042. At that 

point, Portfolio B yield increases significantly more than Portfolio C. For lower average costs, 

the differences between the four portfolios are less significant (figure F-22, left), particularly 

between Portfolio B and Portfolio C. 

6.7 Implementing Dynamic Portfolios in CRSS 

The Study developed these four portfolios as exploratory approaches for addressing future 

supply and demand imbalances. The portfolios represent a preference set for options that may be 

implemented in the future to address imbalances. However, the portfolios are implemented 

dynamically in CRSS modeling such that options are only brought on line as needed to address a 

particular vulnerability. For example, if a particular future only requires 2 mafy of additional 

options to address the vulnerabilities, then only a portion of the portfolio list of options would be 

implemented. Similarly, if the vulnerability that arises in the scenario of the future is regionally 

specific, then only those options that can address the regional vulnerability would be 
Colorado River Basin

Water Supply and Demand Study

F-86 December 2012

implemented. As a result, the outcome of the modeling analysis of each portfolio under future 

plausible combinations of supply and demand will be a range of option implementation, portfolio 

yields, and portfolio costs. Additional detail on the implementation and results of the portfolio 

analysis is described in Technical Report G – System Reliability Analysis and Evaluation of 

Options and Strategies. 

FIGURE F-22

Total Yields over Time for Average Costs less than or equal to $750 per af (left), $1,000 per af (center) and $1,250 per af (right) 

for Portfolios

7.0 Summary and Limitations

In response to projections of increasing imbalance between Colorado River water supply and 

water demand, a process was developed to identify and develop options and strategies to mitigate 

and adapt to the potential impacts to Basin resources. The process involved identification and 

characterization of options that may be used to address imbalances, and development of 

portfolios of options that explore a range of strategies to adapt to evolving imbalances over time. 

The activities that comprise the options and strategies process were carried out through a 

collaborative process involving representatives of numerous organizations, including 

Reclamation, the Basin States, tribes and communities, and conservation organizations. 

Approximately 160 options were received as part of the solicitation for ideas to resolve 

imbalances. The options were reviewed and organized into option types and categories for 

further analysis. Each submitted option was assigned to one category based on its primary 
Technical Report F — Development

of Options and Strategies

December 2012 F-87

function, and from these categories, about 40 unique representative options were described to 

capture the range of options submitted to and considered in the Study. A set of 17 

characterization criteria were identified and described reflecting the option attributes of interest 

in the Study. For each of the options, a qualitative letter score from A through E was assigned for 

each criterion. However, some options, such as many in the System Operations category, all in 

the Governance and Implementation category, and those related to tribal water use were 

considered in a qualitative manner not directly associated with the criteria. 

Because it is recognized that no single option is likely to address the all of the projected 

imbalances between supply and demand, four exploratory portfolios consisting of combinations 

of options were developed. Options were selected for inclusion in the portfolios based on the 

option characteristics and the overall strategy chose for a given portfolio. The portfolios contain 

unique sets of options, potential yield, cost, other attributes, and operational measures that 

represent a broad range of future adaptation possibilities. The effect of portfolio implementation 

at addressing vulnerable system conditions that may be present under future water supply and 

demand scenarios is described in Technical Report G – System Reliability Analysis and 

Evaluation of Options and Strategies. 

The process undertaken in identifying and developing the options and strategies aimed at

establishing an objective, and consistent process for evaluation. However, the evaluation of 

options was performed at a limited and high level, consistent with the broad range of options 

submitted. Limiting the level of analysis helped ensure that all options were considered at a 

consistent, high level, but limited the characterization of options in further detail. Although all 

attempts were made to make the evaluation of options as objective as possible, the evaluation of 

a broad range of options for such a wide array of criteria cannot fully remove all subjectivity. 

The assumptions have been documented, and the Options and Strategies Sub-Team was 

encouraged to challenge assumptions in the initial ratings. Not all members of the Sub-Team 

were in agreement with all ratings but recognized that future efforts may result in a more indepth assessment of the selected criteria. 

Finally, the four portfolios considered in the Study represent different potential strategies for 

dynamically addressing system vulnerabilities that may develop in the future. Because there are 

many more strategies than could have been evaluated in the Study, the portfolios should be 

considered as exploratory. The primary focus of portfolio development and subsequent 

evaluation in the Study is to determine the range of responses, types of options implemented, the 

effectiveness at addressing vulnerabilities, and the range of cost and other attributes that result 

from different portfolio implementations.

8.0 References 

Bureau of Reclamation (Reclamation). 2011. Phase 4: Development and Evaluation of 

Opportunities for Balancing Water Supply and Demand - Request for Ideas.

CALFED. 2006. Water Use Efficiency Comprehensive Evaluation. 

California Water Code. 2010. Retrieved from http://www.leginfo.ca.gov/cgibin/calawquery?codesection=wat. 

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for Water 

Supply of the Colorado River System. 
Colorado River Basin

Water Supply and Demand Study

F-88 December 2012

Colorado Water Conservation Board. 2011. SWSI 2010 Municipal and Industrial Water 

Conservation Strategies. 

Colorado Water Institute. 2011. Relative Costs of New Water Supply Opportunities for Front 

Range Cities. June. 

Cooley, H., J. Chrisian-Smith, P.H. Gleick, M.J. Cohen, and M. Heberger. 2010. California’s 

Next Million Acre-Feet: Saving Water, Energy, and Money. 

Imperial Irrigation District (IID). 2012. 2012-2013 Land Fallowing Program. Retrieved July 

2012, from http://www.iid.com/index.aspx?page=190. 

Imperial Irrigation District (IID). 2007. Imperial Irrigation District Efficiency Conservation 

Definite Plan. 

Mississippi State University Extension Service. 2009. Starting a Greenhouse Business. 

Publication 1957. 

Pacific Institute. 2011. Municipal Deliveries of Colorado River Basin Water. 

Painter, T. H., A. P. Barrett, C. C. Landry, J. C. Neff, M. P. Cassidy, C. R. Lawrence, K. E. 

McBride, and G. L. Farmer. 2007. “Impact of disturbed desert soils on duration of 

mountain snow cover.” Geophys. Res. Lett., 34, L12502, doi:10.1029/2007GL030284. 

Painter T, Deems J, Belnap J, Hamlet A, Landry C, and Udall B. 2010. “Response of Colorado 

River runoff to dust radiative forcing in snow.” Proceedings of the National Academy of 

Sciences.

Research & Planning Consultants. 2000. Assessment of Brush Control as a Water Management 

Strategy. 

Skiles, S. M., T. H. Painter, J. S. Deems, A. C. Bryant, and C. C. Landry. 2012. “Dust radiative 

forcing in snow of the Upper Colorado River Basin: 2. Interannual variability in radiative 

forcing and snowmelt rates” Water Resour. Res., 48, W07522, 

doi:10.1029/2012WR011986. 

SPG Solar. 2007. Far Niente Winery Case Study. 

Tamarisk Coalition. 2009. Colorado River Basin Tamarisk and Russian Olive Assessment. 

Whittaker, Doug. 2005. Flows and Recreation: A Guide to Studies for River Professionals. 

Hydropower Reform Coalition and National Park Service – Hydropower Recreation 

Assistance. 

U.S. Department of Agriculture. 2003. Greenhouse Tomatoes Change the Dynamics of the North 

American Fresh Tomato Industry. Economic Research Service. ERR-2. 

U.S. Department of Interior (DOI). 2007. Record of Decision for Colorado River Interim 

Guidelines for Lower Basin Shortages and Coordinated Operations for Lake Powell and 

Lake Mead. 

U.S Geological Survey (USGS). 2006. Evaporation from Lake Mead, Arizona and Nevada, 

1997-99. U.S. Geological Survey, Scientific Investigations Report 2006-5252. 
Technical Report F — Development

of Options and Strategies

December 2012 F-89

Disclaimer

The Colorado River Basin Water Supply and Demand Study (Study) is funded jointly by the Bureau of 

Reclamation (Reclamation) and the seven Colorado River Basin States (Basin States). The purpose of 

the Study is to analyze water supply and demand imbalances throughout the Colorado River Basin and 

those adjacent areas of the Basin States that receive Colorado River water through 2060; and develop, 

assess, and evaluate options and strategies to address the current and projected imbalances. 

Reclamation and the Basin States intend that the Study will promote and facilitate cooperation and 

communication throughout the Basin regarding the reliability of the system to continue to meet Basin 

needs and the strategies that may be considered to ensure that reliability. Reclamation and the Basin 

States recognize the Study was constrained by funding, timing, and technological and other limitations, 

and in some cases presented specific policy questions and issues, particularly related to modeling 

and interpretation of the provisions of the Law of the River during the course of the Study. In such 

cases, Reclamation and the Basin States developed and incorporated assumptions to further complete 

the Study. Where possible, a range of assumptions was typically used to identify the sensitivity of the 

results to those assumptions.

Nothing in the Study, however, is intended for use against any Basin State, any federally recognized 

tribe, the federal government or the Upper Colorado River Commission in administrative, judicial or 

other proceedings to evidence legal interpretations of the Law of the River. As such, assumptions 

contained in the Study or any reports generated during the Study do not, and shall not, represent a legal 

position or interpretation by the Basin States, any federally recognized tribe, federal government or 

Upper Colorado River Commission as it relates to the Law of the River. Furthermore, nothing in the 

Study is intended to, nor shall the Study be construed so as to, interpret, diminish or modify the rights 

of any Basin State, any federally recognized tribe, the federal government, or the Upper Colorado River 

Commission under federal or state law or administrative rule, regulation or guideline, including without 

limitation the Colorado River Compact (45 Stat. 1057), the Upper Colorado River Basin Compact 

(63 Stat. 31), the Utilization of Waters of the Colorado and Tijuana Rivers and of the Rio Grande, 

Treaty Between the United States of America and Mexico (Treaty Series 994, 59 Stat. 1219), the 

United States/Mexico agreement in Minute No. 242 of August 30, 1973 (Treaty Series 7708; 24 UST 

1968), or Minute No. 314 of November 26, 2008, or Minute No. 318 of December 17, 2010, or Minute 

No. 319 of November 20, 2012, the Consolidated Decree entered by the Supreme Court of the United 

States in Arizona v. California (547 U.S 150 (2006)), the Boulder Canyon Project Act (45 Stat. 1057), 

the Boulder Canyon Project Adjustment Act (54 Stat. 774; 43 U.S.C. 618a), the Colorado River 

Storage Project Act of 1956 (70 Stat. 105; 43 U.S.C. 620), the Colorado River Basin Project Act of 

1968 (82 Stat. 885; 43 U.S.C. 1501), the Colorado River Basin Salinity Control Act (88 Stat. 266; 43 

U.S.C. 1951) as amended, the Hoover Power Plant Act of 1984 (98 Stat. 1333), the Colorado River 

Floodway Protection Act (100 Stat. 1129; 43 U.S.C. 1600), the Grand Canyon Protection Act of 1992 

(Title XVIII of Public Law 102-575, 106 Stat. 4669), or the Hoover Power Allocation Act of 2011 

(Public Law 112-72). In addition, nothing in the Study is intended to, nor shall the Study be construed 

so as to, interpret, diminish or modify the rights of any federally recognized tribe, pursuant to 

federal court decrees, state court decrees, treaties, agreements, executive orders and federal trust 

responsibility. Reclamation and the Basin States continue to recognize the entitlement and right of 

each State and any federally recognized tribe under existing law, to use and develop the water of the 

Colorado River system.
Appendix F1

Options and Strategies Sub-Team Members

December 2012 F1-1

Appendix F1 — Options and Strategies

Sub-Team Members

The information presented in Technical Report F – Development of Options and Strategies is the 

outcome of a collaborative process involving representatives of numerous organizations. 

A list of Options and Strategies Sub-Team members and their affiliations is presented below. 

Perri Benemelis, Arizona Department of Water Resources

Don Gross, Arizona Department of Water Resources

Les Lampe, Black & Veatch

Klint Reedy, Black & Veatch

Alan Butler, Bureau of Reclamation

Carly Jerla, Bureau of Reclamation

Ken Nowak, Bureau of Reclamation

James Prairie, Bureau of Reclamation

Chuck Cullom, Central Arizona Project

Armin Munévar, CH2M HILL 

Greg Gates, CH2M HILL

Chris Harris, Colorado River Board of California

Lindia Liu, Colorado River Board of California

Dave Kanzer, Colorado River Water Conservation District

Ted Kowalski, Colorado Water Conservation Board

Jennifer Pitt, Environmental Defense Fund

John Carter, Imperial Irrigation District

Kevin Flanigan, New Mexico Interstate Stream Commission

Estevan Lopez, New Mexico Interstate Stream Commission

Jordan Fischbach, RAND Corporation

David Groves, RAND Corporation

Kay Brothers, Southern Nevada Water Authority

Tom Maher, Southern Nevada Water Authority

Bruce Moore, Southern Nevada Water Authority

Cathy Condon, Ten Tribes Partnership 

Jason John, Ten Tribes Partnership 

Bill Hasencamp, The Metropolitan Water District of Southern California

Jan Matusak, The Metropolitan Water District of Southern California

Taylor Hawes, The Nature Conservancy

Melinda Kassen, Trout Unlimited

Erin Wilson, Wilson Water Group

John Shields, Wyoming State Engineer’s Office

Appendix F2 

Options Submitted to the Study

Appendix F2 — Options Submitted to the 

Study 

1.0 Introduction

In November 2011, the Colorado River Basin Water Supply and Demand Study (Study) 

began its fourth and final phase: Evaluation of Opportunities for Supply and Demand. From 

November 2011 through February 2012, the Study solicited public input on options and 

strategies for helping to resolve future water supply and demand imbalances in the Colorado 

River Basin (Basin). The Study cost-share partners sought input from a broad range of 

stakeholders and interested parties located within as well as external to the Basin. 

A report by the Bureau of Reclamation (Reclamation), Phase 4: Development and 

Evaluation of Opportunities for Balancing Water Supply and Demand – Request for Ideas,

(Reclamation, 2011) was published to provide relevant information to those interested in 

submitting input. The report provided a summary of previous studies that assessed future 

imbalances and explored options and strategies, and described ongoing efforts for balancing 

Basin supply and demand. Project participants and stakeholders were encouraged to submit 

ideas related to options and strategies that could help to resolve future supply and demand 

imbalances in the Basin by February 1, 2012. 

A total of 160 options were received. The submittals, as received, are available in electronic 

portable document format on the compact disc that accompanies this report and at the Study 

website at http://www.usbr.gov/lc/region/programs/crbstudy.html. The options were 

separated into four types based on their approach for resolving the imbalance: Increase 

Supply, Reduce Demand, Modify Operations, and Governance and Implementation. 

Approximately 55 options were submitted that related to increasing supply, 42 options 

related to reducing demand, 22 options related to modifying operations, and 41 options 

related to governance and implementation. The options were further organized into 

categories and groups, from which representative options were developed for consideration 

in the analysis, as follows: 

• Increase Supply: This type included suggestions for importing water into the Basin from 

the Green River, Snake River, via ocean routes, or through exchanges with Missouri and 

Mississippi rivers’ supply; desalination projects along the Pacific Ocean, along the Gulf 

of California, or brackish water desalting projects in California and Arizona; wastewater 

reuse; greater use of local supplies; and application of watershed management techniques 

such as weather modification or vegetation control to increase supply. 

• Reduce Demand: This type included suggestions for municipal and industrial water

conservation, agricultural water conservation, energy water use efficiency, and methods 

for reducing evaporation from lakes and canals. 

• Modify Operations: This type included suggestions for changing system operations, 

augmenting storage, and including water banking and transfer programs. 

December 2012 F2-1 
• Governance and Implementation: These suggestions are related to changes in policy, 

management, legal structure, or future implementation and governance of the Colorado 

River system. 

Table F2-1 summarizes the submittals and the original submittals are available via links from 

the electronic version of this appendix available on the compact disc that accompanies this 

report and the version of this appendix on the Study website at 

http://www.usbr.gov/lc/region/programs/crbstudy.html. 

Colorado River Basin 

Water Supply and Demand Study 

F2-2 December 2012 
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Increase Supply Importation Imports to the Green River 

Headwaters

Snake River Imports 4 Colorado River Augmentation – Snake 

River Import

Increase Supply Importation Imports to the Green River 

Headwaters

Snake River Imports 39 Import flows from the Snake River to the 

Green River

Increase Supply Importation Imports to the Green River 

Headwaters

Snake River Imports 47 Colorado River Augmentation – Clark’s 

Fork to Green River Import

Increase Supply Importation Imports to the Green River 

Headwaters

Bear River Imports 46 Colorado River Augmentation – Bear River 

to Ham’s Fork Creek Import

Increase Supply Importation Imports to the Green River 

Headwaters

Yellowstone River Imports 158 Imports from Tributaries of the Columbia 

River

Increase Supply Importation Imports to the Colorado 

Front Range

Missouri River Imports 12 Surface Water Importation – Missouri River

Increase Supply Importation Imports to the Colorado 

Front Range

Missouri River Imports 50 Missouri River Reuse Project (Front 

Range)

Increase Supply Importation Imports to the Colorado 

Front Range

Missouri River Imports 155 Midwest Imports

Increase Supply Importation Imports to the Colorado 

Front Range

Missouri River Imports 157 Import Water from Floodplains

Increase Supply Importation Imports to the Colorado 

Front Range

Missouri River Imports 159 Missouri River Reuse Project (Front Range 

+ Rio Grande)

Increase Supply Importation Imports to the Colorado 

Front Range

Mississippi River Imports 52 Mississippi River Supply

Increase Supply Importation Imports to Southern 

California

Tankers 14 Water Imports Using Ocean Routes – 

Tankers

Increase Supply Importation Imports to Southern 

California 

Water Bags 15 Water Imports Using Ocean Routes – 

Water Bags

Increase Supply Importation Imports to Southern 

California 

Icebergs 16 Water Imports Using Ocean Routes – 

Icebergs

Increase Supply Importation Imports to Southern 

California 

Columbia River Imports 49 Colorado River Augmentation – Columbia 

River via a Submarine Pipeline

Appendix F2 — Options 

 Submitted to the Study 

December 2012 F2-3 
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in California

6 Pacific Ocean Desalination

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in California

11 Desalination in California – Subsidized by 

Nevada and Arizona

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in California and Mexico

40 Widespread Desalination – San Francisco, 

Salton Sea, Puerto Penase, Mexicali 

Mexico; Rio Grande, Houston Area.

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in California and Mexico

103 Desalination Augmentation

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in California

128 Water for West Project

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in California

156 Implement Desalination and Reuse 

Concepts

Increase Supply Desalination Ocean Desalination Pacific Ocean Desalination 

in Mexico

108 Rosarito Beach Binational Seawater 

Desalination Plant

Increase Supply Desalination Ocean Desalination Gulf of California 

Desalination

30 Desalination – Sea of Cortez

Increase Supply Desalination Ocean Desalination Gulf of California 

Desalination

110 Gulf of California Desalination

Increase Supply Desalination Desalination of Agricultural

Drainwater

Salton Sea Drainwater 

Reuse

137 Colorado River Aqueduct Desalination and 

Salton Sea Water Supply Project

Increase Supply Desalination Desalination of Agricultural

Drainwater

Salton Sea Drainwater 

Reuse

139 Salton Sea Restoration and Drainwater 

Reuse

Increase Supply Desalination Desalination of Brackish 

Groundwater

Southern California 

Groundwater Desalination

24 Desalination of Brackish Groundwater – 

Yuma, AZ and Riverside County, CA

Increase Supply Desalination Desalination of Brackish 

Groundwater

Southern California 

Groundwater Desalination

143 Southern California Groundwater 

Desalination

Increase Supply Desalination Desalination of Brackish 

Groundwater

Brackish Water Desalting in 

Yuma Area

140 Brackish Water Desalting in Yuma Area

Colorado River Basin 

Water Supply and Demand Study 

F2-4 December 2012 
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Increase Supply Desalination Desalination of 

Groundwater

Brackish Brackish Water 

Yuma Area

Desalting in 162 Yuma-Mesa Barrier Dam 

Collector System Project

and Water 

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 7 Mega Reuse in Southern Coast California

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 26 Water Reuse/Recycling

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 104 Water Reuse/Recycling

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 141 Water Reuse in Front Range Colorado

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal

Reuse

Wastewater 142 Water Reuse Along Wasatch Front

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 145 Water Reuse in Central Arizona

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 160 Water Reuse – New Mexico's Urban Areas

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 161 Water Reuse – Wyoming's Urban Areas

Increase Supply Reuse Municipal 

Reuse

Wastewater Municipal 

Reuse

Wastewater 98 Water Conservation and Management

Increase Supply Reuse Grey Water Reuse Grey Water Reuse 3 Grey Water Recycling System

Increase Supply Reuse Industrial 

Reuse

Wastewater Industrial 

Reuse

Wastewater 152 Industrial Reuse

Increase Supply Local Supply Rainwater Harvesting Rainwater Harvesting 17 Individual

Barrels) 

 Conservation and Storage (Rain 

Increase Supply Local Supply Rainwater Harvesting Rainwater Harvesting 22 Rainwater Capture Diverted to Lake Mead

Increase Supply Local Supply Coal Bed Methaneproduced WaterCoal Bed Methaneproduced Water42 Consider Adequate Supplies 

Industries in the Future

to Oil and Gas 

Appendix F2 — Options 

 Submitted to the Study 

December 2012 F2-5 
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Increase Supply Local Supply Coal Bed Methaneproduced WaterCoal Bed Methaneproduced Water51 Coal Bed Methane Produced Water

Increase Supply Watershed 

Management

Brush Control Brush Control 5 Brush Control on BLM Land

Increase Supply Watershed 

Management

Dust Control Dust Control 33 Development of a Dust Mitigation Program

Increase Supply Watershed 

Management

Dust Control Dust Control 59 Dust Abatement

Recovery

for Colorado River Flow 

Increase Supply Watershed 

Management

Dust Control Dust Control 92 Air Quality Improvement/Reduction of 

causing Snow to Melt

Soot 

Increase Supply Watershed 

Management

Forest Management Forest Management 48 Forest Management – Increased Harvest

Increase Supply Watershed 

Management

Forest Management Forest Management 125 Forest Management 

Wildfires

Strategies to Reduce 

Increase Supply Watershed 

Management

Weather Modification Weather Modification 89 Precipitation Enhancement 

(Weather Modification)

/ Cloud Seeding 

Increase Supply Watershed 

Management

Weather Modification Weather Modification 129 Weather 

Seeding)

Modification Program (i.e. Cloud 

Increase Supply Watershed 

Management

Weather Modification Weather Modification 153 Increase Rainfall 

Seas

by Creating More Inland 

Increase Supply Watershed 

Management

Tamarisk Control Tamarisk Control 130 Strategic Management of Tamarisk

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 9 Residential housing water leak reduction

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 23 Eliminate Water Needy Plants

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 25 Municipal Efficiency: 1% per Year 

Colorado River Basin 

Water Supply and Demand Study 

F2-6 December 2012
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 27 Water Efficiency Action Network of the 

Colorado River Basin (WEAN-CRB)

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 29 Mandate water saving technologies 

large water users

for 

Reduce 

Demand

Municipal/

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 32 Prohibit/Eliminate 

Diversions

New Large-Scale 

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 41 Urban Water 

Conservation

Demand Management and 

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 43 Evaporation reduction by limiting manmade water bodies including pools, lakes 

and water parks.

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 45 Reduce Outdoor Water Use

Reduce 

Demand

Municipal/

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 58 Conservation Instead of 

pipeline

Lake Powell 

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 61 Geyser Flow Control Device

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 69 Municipal Efficiency 1 percent per year

Reduce 

Demand

Municipal/Industri

al Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 70 Water Loss Control and Reduction

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 71 Landscape Design Regulations

Appendix F2 — Options 

 Submitted to the Study 

December 2012 F2-7 
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 72 Landscape Water Budgets

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 73 Enforcement of Water Waste Ordinances

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 74 Water Audits

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 75 Public Education and Awareness 

Campaigns

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 76 Lawns to Xeriscape

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 77 Inclining Block Rates

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 78 Residential Retrofits

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 79 Commercial Retrofits

Reduce 

Demand

Municipal/

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 80 Metering Multi-Family Use

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 81 Pool Covers

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 107 Change of current water policies

Colorado River Basin 

Water Supply and Demand Study 

F2-8 December 2012
Appendix F2 — Options 

 Submitted to the Study 

TABLE F2-1 

Summary of Options Received

December 2012 F2-9 

Option Type Option Category Option Group Representative Option Record No. Option Name

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 119 Colorado River Basin-Wide Per 

Water Use Goal

Capita 

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 131 Proposal to include water savings from the 

implementation of new product standards in 

baseline water use projections

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 132 Proposal to include water savings from 

proposed product standards in 

conservation scenario demand projections

Reduce 

Demand

Municipal/ 

Industrial Water 

Conservation

Municipal/Industrial 

Conservation

Water Municipal/Industrial 

Conservation

Water 151 Assisted/Smart Irrigation and Precision 

farming (fertilizer applications) in urban 

settings

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation

19 Assisted/Smart Irrigation and Precision 

Farming in Agricultural Settings

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation

53 Agricultural Conservation and Efficiency

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation

54 Irrigation Infrastructure Modernization 

Program to Improve Efficiency

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation

83 Reduction of On-farm and Conveyance 

Evaporative Losses and Deep Percolation.

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation

90 Watershed Management Improvements 

(Soil Grouting, Irrigation Practices, Utilizing 

Stock Ponds and Small Divers

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation with Water 

Transfers

31 Conversion to Controlled Environment 

Agriculture (greenhouse production)

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation with Water 

Transfers

99 Water Pricing Reform
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation with Water 

Transfers

118 Reduce Cattle Production and Beef 

Demand

Reduce 

Demand

Agricultural 

Water 

Conservation

Agricultural Water 

Conservation

Agricultural Water 

Conservation with Water 

Transfers

138 Agricultural Field 

Native Grasses

Restoration Utilizing 

Reduce 

Demand

Energy Water 

Use Efficiency

Conversion of 

to Air Cooling

Power Plants Conversion of 

to Air Cooling

Power Plants 13 Power Plant Air Cooling Conversion – 

Navajo Generating Station

Reduce 

Demand

Energy Water 

Use Efficiency

Energy Conservation Water 

the Oil 

Use Efficiencies in 

and Gas Industry

18 Reform of Gas and Oil Industry

Reduce 

Demand

Energy Water 

Use Efficiency

Conversion of 

to Air Cooling

Power Plants Conversion of 

to Air Cooling

Power Plants 28 Demand Management 

Power Plants

at Thermoelectric 

Reduce 

Demand

Energy Water 

Use Efficiency

Energy Conservation Water 

the Oil 

Use Efficiencies in 

and Gas Industry

126 Reducing Energy 

Consumption

Industry’s Water 

Modify 

Operations

System 

Operations 

Evaporation Control Covers Solar Panel 

Covers

Reservoir 1 Evaporation Reduction via 

Systems

Floatovoltaics 

Modify 

Operations

System 

Operations

Evaporation Control Covers Solar Panel 

Covers

Reservoir 86 Reduce Surface Water Evaporation via 

Floating Photovoltaics or Plastic Balls

Modify 

Operations

System 

Operations

Evaporation Control Covers Solar Panel 

Covers

Reservoir 44 Evaporation Reduction from 

and Canals

Reservoirs 

Modify 

Operations

System 

Operations

Evaporation Control Covers Solar Panel Canal Covers 10 Evaporation Reduction at Canals 

Covering with Solar Panels

by 

Modify 

Operations

System 

Operations

Evaporation Control Covers Chemical Type Covers 133 Eliminating Water Loss 

Evaporation by 50%

by Cutting 

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Reduce Reservoir 

Evaporation

37 Optimization Study of Evaporation Loss

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Reduce Reservoir 

Evaporation

136 Reservoir Evaporation Control

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Prioritize Lake Mead 

Storage

60 Fill Mead First

Colorado River Basin 

Water Supply and Demand Study 

F2-10 December 2012
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Prioritize Lake Mead 

Storage

102 Single Reservoir Water Storage

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Maximize Hydropower 

Generation

111 Aspinall Unit Bypass Reduction Option

Modify

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Maximize Hydropower 

Generation

113 Crystal 

Option

Reservoir Unit Bypass Reduction 

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Maximize Hydropower 

Generation

114 Flaming Gorge Unit 

Option

Bypass Reduction 

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Maximize Hydropower 

Generation

115 Fontenelle Reservoir 

Reduction Option

Unit Bypass 

Modify 

Operations

System 

Operations

Modified Operation of 

Existing Reservoirs

Maximize Hydropower 

Generation

116 Hydropower Minimum 

Protection Option

Generation Elevation 

Modify 

Operations

System 

Operations

Operating for 

Environmental Purposes

Operating for 

Environmental Purposes

20 The One-Dam Solution – Lake Powell 

Removal, Underground Storage and 

Sediment Removal in Lake Mead

Modify 

Operations

System 

Operations

Operating for 

Environmental Purposes

Operating for 

Environmental Purposes

56 Integrated Options to 

Healthy River Flows 

Maintain and Restore 

Modify 

Operations

System 

Operations

Operating for 

Environmental Purposes

Operating for 

Environmental Purposes

65 Integrated Options to 

Healthy River Flows

Maintain and Restore 

Modify 

Operations

System 

Operations

Operating for 

Environmental Purposes

Operating for 

Environmental Purposes

106 Yuma Island Wildlife, 

Improvement

Irrigation and 

Modify 

Operations

System 

Operations

Operating for 

Environmental Purposes

Operating for 

Environmental Purposes

124 Integrated Options to 

Healthy River Flows

Maintain and Restore 

Modify 

Operations

System 

Operations

New Water Storage New Water Storage 154 Pump Storage in Upper Basin Headwaters

Modify 

Operations

System 

Operations

New Water Storage New Water Storage 85 Reservoirs such as Drop 2

Modify 

Operations

System 

Operations

New Water Storage Improved Groundwater 

Management

63 Improved Groundwater Management

December 2012 F2-11

Appendix F2 — Options

Submitted to the Study
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Water Transfers, 

Exchanges

Water Transfers 

Exchanges

and 101 Water Banking and Transfer Scheme

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Water Transfers, 

Exchanges

Water Transfers 

Exchanges

and 120 Facilitating Voluntary 

Project Water

Transfers of Federal 

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Guided Water Markets Guided Water Markets 62 Guided Water Markets 

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Guided Water Markets Guided Water Markets 121 Guided Water Markets 

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Upper Basin Water Banking Upper Basin Water Banking 55 ICS in the Upper Basin

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Upper Basin Water Banking Upper Basin Water Banking 64 Individual State-based Water 

Upper Basin 

Banks in the 

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Upper Basin Water Banking Upper Basin Water Banking 95 Upper Basin Water Bank

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Upper Basin Water Banking Upper Basin Water Banking 123 Individual State-based Water 

Upper Basin 

Banks in the 

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Upper Basin Water Banking Upper Basin Water Banking 127 Upper Basin Water Bank 

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Lower Basin Water Banking Lower Basin Water Banking 35 Lower Basin Water Banking

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Lower Basin Water Banking Lower Basin Water Banking 68 Lower Basin Water Bank

F2-12 December 2012

Colorado River Basin 

Water Supply and Demand Study 
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Groundwater Banking Groundwater Banking 87 Groundwater Banking Credits

Governance and 

Implementation

Water Transfers, 

Exchanges, and 

Banking

Groundwater Banking Groundwater Banking 100 Aquifer Storage and Recovery

Governance and 

Implementation

Water 

Management 

Allocation

and 

Changes 

of Water 

to Apportionment 

Supply

Changes 

of Water 

to Apportionment 

Supply

21 The One-Dam Solution – 

Colorado River Compact

Re-examine the 

Governance and 

Implementation

Water 

Management 

Allocation

and 

Changes 

of Water 

to Apportionment 

Supply

Changes 

of Water 

to Apportionment 

Supply

36 Mutual 

Basins

Forbearance by Upper and Lower 

Governance and 

Implementation

Water 

Management 

Allocation

and 

Changes 

of Water 

to Apportionment 

Supply

Changes 

of Water 

to Apportionment 

Supply

38 Colorado River Basin 

based on population

Flow Re-distribution 

Governance and 

Implementation

Water 

Management 

Allocation

and 

Changes 

of Water 

to Apportionment 

Supply

Changes 

of Water 

to Apportionment 

Supply

117 Upper Basin Voluntary Demand Cap

Governance and 

Implementation

Water 

Management 

Allocation

and 

Process for Expanded 

Stakeholder Involvement

Process for Expanded 

Stakeholder Involvement

34 Informal Basin-wide Stakeholder 

Governance Process

Governance and 

Implementation

Water 

Management 

Allocation

and 

Process for Expanded 

Stakeholder Involvement

Process for Expanded 

Stakeholder Involvement

135 Colorado River 

Committee

Basin Blue Ribbon 

Governance and 

Implementation

Water 

Management 

Allocation

and 

Population Control Population Control 2 Conversations 

area

to limit growth in subject 

Governance and 

Implementation

Water 

Management 

Allocation

and 

Population Control Population Control 57 Reverse Migration

Appendix F2 — Options 

 Submitted to the Study 

December 2012 F2-13
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Governance and 

Implementation

Water 

Management 

Allocation

and 

Conservation and Trust 

Funds

Conservation and Trust 

Funds

67 Leveraging utility scale water efficiency 

programs to support local and regional 

environmental enhancement using the 

Conserve to Enhance mechanism

Governance and 

Implementation

Water 

Management 

Allocation

and 

Conservation and Trust 

Funds

Conservation and Trust 

Funds

88 Financial Tools Allowing New Development 

to Pay for the Development of New Local 

Supplies

Governance and 

Implementation

Water 

Management 

Allocation

and 

Conservation and Trust 

Funds

Conservation and Trust 

Funds

91 Removal of Invasive Plants Species

Governance and 

Implementation

Water 

Management 

Allocation

and 

Conservation and Trust 

Funds

Conservation and Trust 

Funds

112 Colorado River Climate Change Adaptation 

& Environmental Trust Fund

Governance and 

Implementation

Tribal Water Voluntary 

Transfers

Tribal Water Voluntary 

Transfers

Tribal Water 66 Inter-Basin (Upper Basin to 

Leasing of Ute Indian Tribal 

Lower 

Water

Basin) 

Governance and 

Implementation

Tribal Water Voluntary 

Transfers

Tribal Water Voluntary 

Transfers

Tribal Water 96 Upper Basin, Interstate Leasing of 

Indian Tribal Water

Ute 

Governance and 

Implementation

Tribal Water Voluntary 

Transfers

Tribal Water Voluntary 

Transfers

Tribal Water 109 Tribal Efficiencies 

Transfers

and Voluntary Water 

Governance and 

Implementation

Tribal Water Voluntary 

Transfers

Tribal Water Voluntary 

Transfers

Tribal Water 144 Voluntary Tribal Water Transfers

Governance and 

Implementation

Tribal Water Tribal Water 

Intentionally 

Surplus 

Storage and 

Created 

Tribal Water 

Intentionally 

Surplus 

Storage and 

Created 

82 Recognition of the Ute Tribe’s 

Water Right in Storage

reserved 

Governance and 

Implementation

Tribal Water Tribal Water 

Intentionally 

Surplus 

Storage and 

Created 

Tribal Water 

Intentionally 

Surplus 

Storage and 

Created 

146 Beneficial 

by Tribes

Water Use of All Tribal Waters 

Governance and 

Implementation

Tribal Water Inter-governmental Forum Inter-governmental Forum 163 Inter-governmental Forum

Governance and 

Implementation

Tribal Water Resolution of Tribal Claims Resolution of Tribal Claims 134 Expeditious Resolution of All Tribal Claims

Colorado River Basin 

Water Supply and Demand Study 

F2-14 December 2012
TABLE F2-1 

Summary of Options Received

Option Type Option Category Option Group Representative Option Record No. Option Name

Governance and 

Implementation

Tribal Water Affordability of Tribal 

Waters via Central Arizona 

Project 

Affordability of Tribal 

Waters via Central Arizona 

Project 

147 Affordability 

Canal

of Tribal Waters Via the CAP 

Governance and 

Implementation

Tribal Water Barriers to Tribal 

Participation in Federal 

Programs 

Barriers to Tribal 

Participation in Federal 

Programs 

148 Remove Barriers On Tribal 

Programs Impacting Water 

Access to 

Management

Governance and 

Implementation

Tribal Water Recognition of Limits Recognition of Limits 149 All Communities 

Available Water 

Must Respect 

in System

Limits of 

Governance and 

Implementation

Tribal Water Stabilization of Soil Stabilization of Soil 150 Flow Augmentation by Soil Stabilization

Governance and 

Implementation

Tribal Water Non-Tributary 

Use

Groundwater Non-Tributary 

Use

Groundwater 97 Ute Indian Tribe Groundwater Use

Governance and 

Implementation

Tribal Water Protection Against 

allocation

Over- Protection Against 

allocation

Over- 84 Establishment of a “Safety Net” to Ensure 

the Ute Indian Tribe’s Reserved Water 

Rights are Protected from Over-allocation

of the State of Utah’s Apportionment of 

Colorado River Water

Governance and 

Implementation

Data and 

Information

Improved Water Use 

Accounting in the Upper 

Basin 

Improved Water Use 

Accounting in the Upper 

Basin 

94 Upper Basin Accounting

Governance and 

Implementation

Data and 

Information

Colorado River Simulation 

System Modeling 

Improvements

Colorado River Simulation 

System Modeling 

Improvements

122 Inclusion of USGS Stream Gages in 

Colorado River Basin Supply and Demand 

Study

Appendix F2 — Options 

 Submitted to the Study 

December 2012 F2-15
2.0 References 

Bureau of Reclamation (Reclamation). 2011. Phase 4: Development and Evaluation of 

Opportunities for Balancing Water Supply and Demand – Request for Ideas. 

Colorado River Basin 

Water Supply and Demand Study 

F2-16 December 2012 
Appendix F3

Options Characterization Criteria

and Rating Descriptions

December 2012 F3-1

Appendix F3 — Options Characterization 

Criteria and Rating Descriptions

1.0 Introduction

The Plan of Study (see Study Report, Appendix 1 – Plan of Study), laid out specific objectives 

related to the development and evaluation of options evaluated in Phase 4 of the Colorado River 

Basin Study (Study). Options proposed by the Project Team and the general public were 

characterized by the Study Team to describe each of the submitted options, provide a relative 

comparison of the option attributes, and support the eventual development of option portfolios. 

Characterization of the proposed options was based primarily on information provided by the 

option proponents; however, existing literature and/or relevant studies were reviewed to support 

the characterization process.

Characterization of the options was based on 17 evaluation criteria that are consistent with the 

criteria outlined in the Plan of Study. The approach to characterization included the following 

steps for each of the proposed options: 

1) Review the submission of the option for relevance and completeness of data. In some 

cases, clarification or additional information was requested from the proponent if it was 

believed that it was required for appropriate characterization of the option. Options that had 

limited definition or were not directly amenable to characterization through the 17 evaluation 

criteria were identified and cataloged for future consideration but are not characterized here.

2) Validate and refine information submitted by the option proponent. Criteria information 

submitted by the option proponent was compared with similar information in relevant case 

studies or readily available databases to confirm accuracy. If quantitative information was

not readily available for a criterion, the Study Team used its collective expertise and 

experience to qualitatively evaluate information provided by the option proponent. 

3) Characterize each option using a bin classification system. Qualitative or quantitative 

values were generated for each evaluation criterion using information provided by the option 

proponent or through refinements. A characterization summary table was developed for each 

option by assigning each criterion in the option to one of its five classification categories, or 

bins, “A” through “E”. In general, the “A” category is most favorable, whereas the “E”

category is least favorable. If insufficient information was available to assign a criterion to 

one of its classification bins, the associated entry in the option characterization summary 

table was left blank. 

2.0 Characterization Criteria

Characterization of options by the public and Project Team was based on 17 criteria that 

captured important attributes for the Study. The criteria are listed below and are described more 

fully in this appendix and in attachment A. 

1) Quantity of yield 

2) Timing 

3) Cost 
Colorado River Basin 

Water Supply and Demand Study

F3-2 December 2012

4) Technical feasibility 

5) Implementation risks 

6) Long-term viability

7) Operational flexibility

8) Permitting 

9) Energy needs 

10) Energy source

11) Other environmental factors 

12) Recreation

13) Socioeconomics

14) Policy Considerations 

15) Legal

16) Hydropower

17) Water quality

Details about information requested from option proponents, the information confirmation 

approach, and bin classifications for each criterion are given in the following sections. In 

general, each option was provided with a five-point rating (“A” through “E”) for each of the 

criteria. As previously stated, “A” generally represented the most favorable rating and “E” 

represented the least favorable rating for the specific criterion. 

2.1 Quantity of Yield

The quantity of water associated with each option was a key characterization criterion. The 

quantity of yield criterion was not limited to new water supplies, but also included the quantity 

of water saved via demand reduction measures or the quantity of water that could be used in a 

different manner after a modification in system operations. 

The option submittal form requested that the submitter roughly quantify the range of the 

potential amount of water that the option could provide annually over the next 50 years. If 

known, the submitter was also asked to specify any important seasonal (e.g., more water could 

be available in winter) and/or frequency (e.g., more water could likely be available during aboveaverage hydrologic years) considerations. 

Information, analyses, and references provided by the option proponent were reviewed for 

accuracy and completeness. The yield of the proposed option was compared with yields 

estimated in relevant case studies that were readily available. Basic checks of fundamental 

hydrology were performed for some options to assist in refining or validating the quantity of 

yield estimates provided in the submission. 

The classification of each option for this criterion was based on the range of quantity of water 

available. After refining the quantity estimates, each option was assigned to one of five bins 

shown in the characterization matrix in attachment A. It is important to note that some options 

(such as desalination plants) may produce the same amount of water in almost every year; 

however, other options may be dependent on hydrologic conditions and may have varying annual 

quantities. The characterization included documentation of the assumptions behind estimating 

the “average yield” based on research of relevant case studies or as supported by available 

hydrology information.
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-3

2.2 Timing

For this criterion, the essential element was the estimated first year the option could begin 

operation. In order to arrive at the first year of operation, the timing to conduct feasibility 

studies, permitting and environmental documentation, and to implement the option were 

assessed. 

The cumulative duration of (1) feasibility, (2) permitting and environmental documentation, and 

(3) implementation phases constitutes the earliest year of operation. In addition, if the option 

could be implemented in phases, a description of the phasing potential was developed. 

Information, analyses, and references provided by the option proponent were reviewed for 

accuracy and completeness. The timing of the proposed option was compared with those in 

relevant case studies that were readily available. Options that included new large-scale 

infrastructure or significant revisions in operations could take many years for planning, 

permitting, and implementation. When reviewing relevant case studies, the time to complete 

these phases on similar projects was noted.

In addition, the following general assumptions were used in evaluating the timing criteria:

There is a level of urgency that results in persistent and consistent pursuit of the option.

There is generally positive political alignment and political desire to pursue the project.

When possible, timing required for feasibility, permitting, and implementation were

based on similar reference projects.

When the scale of a project was larger than “reference” projects, additional time was

typically allotted but generally not more than 5 additional years (for some projects, this 

could be viewed as optimistic).

When legal or policy challenges were identified, additional time was typically allotted, 

but generally not more than 5 additional years (for some projects, this could be viewed as 

optimistic).

The classification of each option for this criterion was based on an estimate of the total number 

of years for the feasibility, permitting and environmental documentation, and implementation 

phases. In addition to preparing a best estimate of the first year of potential operation, each 

proposed option was assigned to one of five bins shown in the characterization matrix in 

attachment A. 

2.3 Cost

The cost criterion included capital and annual costs expressed in terms of unit costs in dollars per 

acre-foot (af). The cost evaluation used consistent methods and assumptions to better allow for 

comparisons of option costs. 

The option submittal form asked for cost information including capital, operations, maintenance, 

repair, replacement, and any other costs. Information, analyses, and references provided by the 

option proponent were reviewed for accuracy and completeness. The cost estimates provided by 

the option proponent were reviewed and refined, as necessary, to ensure consistency on cost 

estimating procedures and assumptions. The review confirmed that capital expenditures 

included all costs associated with obtaining land, easements, rights-of-way, and permits for 
Colorado River Basin 

Water Supply and Demand Study

F3-4 December 2012

construction and operation. Annual costs include those necessary for the continued operation 

and maintenance (O&M) of the option. Details of the cost evaluation methods and assumption 

are provided in attachment B.

In addition to the assessment of the annualized cost expressed in dollars per af, each option was

assigned to one of five bins shown in the characterization matrix in attachment A. 

2.4 Technical Feasibility

For this criterion, the essential element was the overall technical feasibility of the option based 

on the extent to which the underlying technologies or practices have been widely and reliably 

used.

The option submittal form asked for a description of the technical maturity of the option and 

what research and/or new technologies might be required for implementation. Information, 

analyses, and references provided by the option proponent were reviewed for accuracy and 

completeness. The proposed option was compared with those in relevant case studies, focusing 

on confirming the degree to which option technologies and practices have been previously used 

and proven. If an option was based on technologies and practices that are widely available and 

previously proven, it was considered to be more technically feasible than options based on 

relatively new and unproven technologies or practices.

The classification of each option for this criterion was based on an assessment of whether the 

type of option has been: a) regularly implemented in the United States at the proposed scale, b) 

occasionally or regularly implemented somewhere in the world at similar scale, c) regularly 

implemented at smaller scales, d) has not been implemented, but peer review articles indicate 

promise, or e) has not been implemented and no peer review articles exist or they indicate 

challenges. The bins shown in attachment A match these categories. 

2.5 Implementation Risks

For this criterion, risks separate and distinct from risks associated with technical feasibility, lifecycle cost, permitting, legal and policy considerations, and ongoing system reliability were of 

particular interest. Implementation risks identified for each proposed option were used in a 

qualitative fashion in the characterization of proposed options; however, the actual magnitude of 

individual risks was not quantified.

The option submittal form asked for an identification and description of risk or uncertainty 

related to implementation of the proposed option. Information, analyses, and references 

provided by the option proponent were reviewed for accuracy and completeness. 

Implementation risks associated with the proposed option were compared with similar risks in 

relevant case studies that were readily available. Implementation risks of particular interest 

included the viability of funding mechanisms for infrastructure and facilities construction, 

competing demands for option-specific critical resources, and potential for mitigation 

requirements that may be impractical to achieve. 

For each option, the following checklist was used to assess implementation considerations. 

Based on this assessment, each proposed option will be assigned to one of five bins shown in the 

characterization matrix in attachment A.
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-5

Implementation Risks Checklist

Evaluation of implementation risks is necessarily qualitative because the entities responsible for funding, 

operations, and mitigation cannot be determined at this time. As such, the criterion will consist of a general 

assessment. 

For each checklist item the following options are available for selection:

Does not have this risk.

Has this risk.

Checklist Item Description

Risk of Raising Capital Either large amount of capital required or funding required from entity without 

reliable access to sufficient funds.

Challenging Operations Integrating new supply into existing facilities is feasible, but requires possibly an 

unrealistic degree of operating flexibility or precision. 

Example: Delivering large amounts of ocean desalination water to a potable 

water system in a location that requires extreme precision in operating the 

potable water system or flexibility in terms of coordinating the use of the 

desalted water with use of other supplies.

Challenging Mitigation 

Requirements

Mitigation requirements anticipated to be required under the permitted phase 

results in mitigation operations that are impractical to achieve.

Example: New water supply concept results in in-stream flow changes in a 

certain river reach and the operations require extreme precision in exchanging 

the water into a reservoir and staying within the in-stream flow requirements. 

Another example would be that changes in the flow regime to an 

environmentally sensitive area, such as the Salton Sea or the Cienega de 

Santa Clara, require extensive mitigation.

2.6 Long-term Viability

For this criterion, the anticipated reliability of the option considering its capability to meet 

proposed objectives over the long-term was of particular interest. The option submittal form 

asked for the identification and description of any known risks to supply or demand, such as 

drought risk, water contamination risk, or risk of infrastructure failure. The long-term viability 

rating was essentially a qualitative evaluation of the risk of the option to provide the expected 

quantity of yield benefits in the long term.

Information, analyses, and references provided by the option proponent were reviewed for 

accuracy and completeness. When considering long-term viability, the options were compared 

with similar projects to identify viability risks. Of particular interest were risks related to 

ongoing operations and sustainability of a proposed option that were separate and distinct from 

risks associated with technical feasibility, construction cost, permitting, legal and policy 

considerations, and implementation. When considering operational flexibility, the degree to 

which the option could be operated (or implemented) across a wide range of hydrologic 

conditions, by having the ability to adjust the magnitude of operations each year to meet the 

required conditions was also considered.

Each option was assessed using the following checklist. Based on this assessment, each 

proposed option was assigned to one of five bins shown in the characterization matrix in 

attachment A.
Colorado River Basin 

Water Supply and Demand Study

F3-6 December 2012

Long-term Viability Checklist

For each checklist item the following options are available for selection:

Does not have this risk.

Has this risk.

Checklist Item Description

Intermittent or Uncertain 

Supply

Supply is susceptible to factors that could make it intermittent or uncertain. 

Example: Supplies susceptible to intermittent yield are those that are 

susceptible to drought, climate change, etc. Supplies with limited susceptibility 

are those such as conservation, reuse, ocean supplies, Mississippi River 

supplies, etc. Uncertain supplies are those for which the magnitude of available 

supply is difficult to measure or predict. Examples include options related to 

land management, weather modification, or vegetation management.

Contamination Supply could be lost or cost could significantly increase if water quality changes 

due to “reasonable risk” of contamination.

Example: Groundwater storage project mobilizes arsenic or other mineral that is 

regulated.

Infrastructure Failure Supply depends on infrastructure that is vulnerable to natural disaster or nonnatural disaster.

Example: Offshore ocean desalter that is destroyed by an earthquake and 

resultant tsunami.

O&M Cost Escalation Supply depends on operations that are at some risk to cost inflation.

Example: Options that are power-dependent are at risk of power cost inflation. 

Other O&M risks could be labor-intensive, etc.

Unintended Consequences 

or Behaviors

Supply increase or demand reduction depends on predictability of community 

behavior or acceptance.

Example: Imposition of odd/even day watering restrictions may lead to 

increased water use because “scarcity” perceptions drive greater water use on 

prescribed days.

2.7 Operational Flexibility

The operational flexibility of each option was also characterized based on the ability of the 

option to be idled from year to year. This criterion hints at the flexibility for an option to be used 

in short-term deficit conditions, but scaled back during subsequent wetter conditions with limited 

financial impacts. The specific characterization bins are shown in the matrix in attachment A. 

2.8 Permitting

This criterion provides information related to the permits (number and type) that may be required 

to implement the particular option. The overall list of potentially required permits was the 

important item of information. In particular, a requirement to complete an Environmental Impact 

Statement (EIS) prior to implementation was important. Permitting considerations were used in

a qualitative manner to characterize an option.

The option submittal form asked for a list of the permits required for implementation of the 

option and status of the permitting process if implementation has been initiated. Information, 

analyses, and references provided by the option proponent were reviewed for accuracy and 

completeness. In particular, review of similar case studies demonstrated a comprehensive list of 

permitting requirements for a given option. 
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-7

For each option, the following checklist was used to assess permitting challenges. Based on this 

assessment, each proposed option was assigned to one of five bins shown in the characterization 

matrix in attachment A.

Permitting Items Checklist

For each checklist item, the following assessment will be performed:

Not required or not applicable.

Required, but precedent shows similar options have received permit.

Required, but no precedent exists and permit likelihood is unknown.

Required and precedent shows significant permit challenges.

Check List Item Description

NPDES National Pollution Discharge Elimination System

CWA 404 Clean Water Act, Section 404 Wetlands Permits

CWA 401 Clean Water Act, Section 401 Water Quality Permits

Coastal Commission California Coastal Commission Permits

Land Use Permits For facilities located in or passing through federal, county, state, local 

jurisdictions.

Special Use Permits In public lands or using public facilities (Bureau of Land Management, U.S. 

National Forest Service, etc.)

Fish & Wildlife Federal or state permits

FERC Federal Energy Regulatory Commission

IBWC 1944 Treaty with United Mexican States (Mexico) and subsequent minutes

Other Permits Required international, federal, state, or local permits 

2.9 Energy Needs

For this criterion, the required additional energy to convey, treat, and deliver new supplies was of 

particular interest. These additional energy requirements were separate and distinct from energy 

generated at hydroelectric facilities that might exist at other locations. 

The option submittal form asked for the estimated amount of energy (kilowatt hours [kWh]/af) 

required to convey, treat, and deliver the additional yield provided by the proposed option to the 

proposed locations at a specified water quality. Information, analyses, and references provided 

by the option proponent were reviewed for accuracy and completeness. The energy required 

(kWh/af) to operate the option was estimated using data provided by the option proponent or 

other readily available information from relevant case studies. Raw water quality and target 

finished water quality, as well as distance and elevation difference between supply origination 

and delivery location(s), were used to estimate the required energy (kWh/af) for pumping and 

treatment. Other basic engineering estimates were made for non-traditional water supply 

options.

For each proposed option, the required energy needs were estimated. Each proposed option was 

assigned to one of five bins shown in the characterization matrix in attachment A based on this 

assessment.
Colorado River Basin 

Water Supply and Demand Study

F3-8 December 2012

2.10 Energy Source

For this criterion, the source of any new required energy was of particular interest. Energy 

sources ranging from renewable sources (wind, solar, geothermal, hydropower) to nuclear, 

natural gas, diesel, and coal were assessed.

The option submittal form requested that the anticipated source(s) of any new required energy be 

identified, when applicable. Information, analyses, and references provided by the option 

proponent were reviewed based on known potential for energy sources available to the option. 

In some cases, the energy targeted for the option was reflective of a mix of sources (i.e., Western 

Area Power Administration grid). In those circumstances, the dominant energy source was

identified or simply indicated as “grid” energy sources. 

For each option, an assessment was made regarding whether the option: a) requires no new 

energy, b) uses renewable energy as the primary source of energy, c) uses natural gas or a mix of 

sources from the “grid” as the primary source of energy, d) uses diesel fuel as the primary source 

of energy, or e) uses coal as the primary source of energy. The bins shown in the 

characterization matrix in attachment A match these categories.

2.11 Other Environmental Considerations

For this criterion, ecosystems that might be affected by the proposed option such as aquatic, 

wetland, and riparian habitats were of particular interest. The assessment was qualitative and did

not replace the detailed Colorado River Simulation System (CRSS) modeling of Colorado River 

ecological resources metrics.

The option submittal form requested a description of any potential positive or negative impacts 

on ecosystems within or outside the Basin associated with the proposed option. Information, 

analyses, and references provided by the option proponent were reviewed for accuracy and 

completeness. Relevant environmental assessment/EIS reports also were reviewed and past 

findings of ecosystem impacts associated with concepts similar to those described in the 

proposed option were noted.

For each option, the following checklist was used to guide the assessment of potential 

environmental impacts. Based on this assessment, each proposed option was assigned to one of 

five bins shown in the characterization matrix in attachment A.
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-9

Environmental Items Checklist

For each checklist item, the following options are available for selection:

Significantly positive.

Moderately positive.

No significant change.

Moderately negative.

Significantly negative.

Check List Item Description

Air Quality Positive or negative impacts to dust or any other applicable air quality standard. 

An example would be the extent to which energy needs for an option are being 

met by renewable energy sources such as wind or solar compared to coal-fired 

power plants that produce emissions.

Listed Species Positive or negative impacts, either directly or through habitat modification, on 

species listed as threatened or endangered.

Non-listed Species Positive or negative impacts, either directly or through habitat modification, on 

non-listed species.

Riparian Habitat Positive or negative impacts on riparian habitat or other sensitive natural 

community.

Wetlands Positive or negative impacts on federally protected wetlands (including but not 

limited to marsh, vernal pool, coastal, etc.)

Cultural Positive or negative impacts on historical resources, archaeological sites, 

paleontological sites, or unique geologic features.

Noise Positive or negative impacts on ambient noise levels.

2.12 Recreation

For this criterion, potential impacts to recreational activities throughout the Basin were of 

interest. The assessment was qualitative and did not replace the detailed CRSS modeling of 

Colorado River recreation metrics.

The option submittal form asked for the identification of any positive or negative effects on 

recreation. Information, analyses, and references provided by the option proponent were 

reviewed for accuracy and completeness. Impacts of estimated changes in flow of the proposed 

option on recreational activities were compared with those estimated in relevant case studies that 

were readily available. 

For each option, the following checklist was used to assess potential recreation impacts. Based 

on this assessment, each proposed option was assigned to one of five bins shown in the 

characterization matrix in attachment A.
Colorado River Basin 

Water Supply and Demand Study

F3-10 December 2012

Recreation Items Checklist

For each checklist item, the following options are available for selection:

Significantly positive.

Moderately positive.

No significant change.

Moderately negative.

Significantly negative.

Check List Item Description

Upper Basin 

Recreation Access

Adverse effects to any designated or proposed wild or scenic rivers, trails, 

wilderness areas, or other recreational areas.

Upper Basin 

Lake Levels

Consider the extent to which lake levels decline to levels that adversely affect 

recreation by reducing usability of boat ramps or impairing access to desirable 

boating or fishing areas.

Upper Basin 

Boating Flows

Consider extent to which flows in streams used for boating are reduced and the 

magnitude of impact of the reduced flow on the value of boating in affected 

reaches.

Upper Basin

Visual Impacts

Alteration of any scenic vista or creation of an aesthetically offensive site or 

effect that is open to public view.

Lower Basin 

Recreation Access

Adverse effects to any designated or proposed wild or scenic rivers, trails, 

wilderness areas, or other recreational areas.

Lower Basin 

Lake Levels

Consider the extent to which lake levels decline to levels that adversely affect 

recreation by reducing usability of boat ramps or impairing access to desirable 

boating or fishing areas.

Lower Basin 

Boating Flows

Consider extent to which flows in streams used for boating are reduced and the 

magnitude of impact of the reduced flow on the value of boating in affected 

reaches.

Lower Basin

Visual Impacts

Alteration of any scenic vista or creation of an aesthetically offensive site or 

effect that is open to public view

2.13 Socioeconomics

For this criterion, consideration of potential impacts to the socioeconomic conditions of regions 

within or outside the Basin due to implementation of the option was of particular interest. 

The option submittal form asked for a description of any anticipated positive or negative 

socioeconomic effects. Information, analyses, and references provided by the option proponent 

were reviewed for accuracy and completeness. Changes in demographic use of water and 

location of water use associated with the proposed option were qualitatively estimated. Specific 

public, private, commercial, industrial, and agricultural sectors affected by demographic changes 

in water use were of particular interest. 

For each option, the following checklist was used to assess potential socioeconomic impacts. 

Based on this assessment, each proposed option was assigned to one of five bins shown in the 

characterization matrix in attachment A. 
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-11

Socioeconomic Items Checklist

For each checklist item, the following options are available for selection:

Significantly positive.

Moderately positive.

No significant change.

Moderately negative.

Significantly negative.

Check List Item Description

Employment Positive or negative impacts on construction-related employment, locational 

shift of businesses, employment for O&M, or other employment impacts.

Public Fiscal Cost Positive or negative impacts on capital costs, O&M costs, revenue from 

charges and fees, or regulatory costs. 

Private Cost Positive or negative impacts on homeowner user charges, property taxes, 

special assessments, real estate values, or costs to businesses or industries.

2.14 Policy Considerations

For this criterion, potential changes to existing federal, state, or local policies that concern water 

resources management or water use in order to implement the option were of interest. These 

policies might be promulgated by individual government agencies, inter-governmental groups, 

non-governmental organizations, or utility boards. Policies related to water resource 

management and water use promulgated by government agencies are often codified in laws, 

statutes, or ordinances. As considered here, water policies are separate and distinct from legal 

issues related to water rights, inter-Basin transfers, and international treaties. Policy 

considerations identified for each proposed option were used in a qualitative fashion in 

characterization of proposed options.

The option submittal form asked for the identification and description of changes in federal, 

state, or local policies that may be required for implementation of the proposed option. 

Information, analyses, and references provided by the option proponent were reviewed for 

accuracy and completeness. The Study Team also referred to information from readily available

and relevant case studies to evaluate the policy implications of a proposed option. Water policies 

related to water conservation, land development, or energy exploration were of particular 

interest.

For each option, the following checklist was used to assess policy considerations. Based on this 

assessment, each proposed option was assigned to one of five bins shown in the characterization 

matrix in attachment A.
Colorado River Basin 

Water Supply and Demand Study

F3-12 December 2012

Policy Items Checklist

The following checklist is a means to explore whether the affected jurisdictions have the policies enumerated 

in the list in place. The list is both prospective, such that enumerated policies may need to be enacted, and 

reactive, leading to a search as to whether such policies are in place. The policies are to be explored at all 

levels (federal, state, and local).

For each checklist item, the following options are available for selection:

Consistent with current policy or not applicable.

Requires changes, but precedent shows proposed changes can be publically acceptable.

Requires changes, but no precedent exists and acceptability is unknown.

Required changes and precedent shows significant public acceptance challenges.

Checklist Item Description

Growth management 

policies

Policies are implemented that limit residential, commercial, industrial, or 

infrastructure growth due to limited water availability or other constraints.

Urban land use policies Land use policies are implemented that mandate higher-density lots or limit less 

water-intensive land uses such as golf courses.

Urban water use policies Policies are implemented that mandate water efficiencies possibly with 

maximum gallons per capita mandates.

Public lands policies Policies are adopted that change land use (and water use) on public lands as 

implemented by entities such as the Bureau of Land Management, U.S. 

National Park Service, or U.S. Forest Service.

Forest management 

policies

Policies are adopted that allow the thinning of natural vegetation to reduce 

evapotranspiration. 

Energy resources 

development policies

Policies are implemented that favor domestic development of energy sources 

and consequently favor water use required to develop those energies, but 

mandates are also passed that make sure water is used as efficiently as 

possible.

Agricultural policies Policies are adopted that change the amount of water allowed to be used for 

agriculture in arid regions or limit the type of crops that can be grown in arid 

regions.

Reservoir operation 

policies

Policies are adopted that change the current operating standards for reservoirs 

in the Basin, possibly changing how releases are made to favor environmental 

or recreational flows and with a possible impact to desired hydropower 

operations or divertible water quantities.

Recreation policies Policies are adopted that set target recreational flows or force minimum water 

levels in reservoirs that change the current operating band or release schedules 

from reservoirs.

Transportation policies Policies are adopted that change the location and types of transportation 

infrastructure. An example would be a denser road network in forested areas to 

allow more harvesting, thereby reducing forest density.

Fish and wildlife policies Policies are adopted that change the current operating standards for the rivers 

or reservoirs in the Basin, possibly changing how releases are made to favor 

environmental flows, with a possible impact to desired hydropower operations 

or divertible water quantities.

2.15 Legal 

For this criterion, the various legal constraints and associated legal instruments and measures 

required for implementation of an option were of particular interest. The legal criterion focused

on potential legal hurdles that would need to be addressed to implement each option.
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-13

The option submittal form asked for the identification and description of all required legal 

considerations or agreements or other legal processes required for implementation of the option. 

Information, analyses, and references provided by the option proponent were reviewed for 

accuracy and completeness. Particular emphasis was placed on review of legal requirements for 

implementation of similar options and review of the requirements of the Law of the River. 

Options that would involve interstate or international implementation of options, transfers of the 

rights to use water, or any other inter-jurisdictional cooperation would have documented special 

legal needs.

For each option, the following checklist was used to assess legal challenges. Based on this 

assessment, each proposed option was assigned to one of five bins shown in the characterization 

matrix in attachment A.

Legal Risks Checklist

For each checklist item, the following options are available for selection:

Consistent with current legal framework or item not applicable.

Local or federal laws may require changes, but precedent shows that item can be addressed

Legal action is required, no precedent exists, and timeframe or likelihood of success is unknown.

Legal action is required and precedent shows that the legal challenges may not be overcome.

Checklist Item Description

Law of the River1 Requires potential change in laws, policies, or regulations associated with the 

Law of the River. This particularly applies when variation in state water 

allocations are needed or when existing provisions of the Law of the River will 

not be met.

Water Rights Changes Requires transfers or leasing of water rights or changes in the conditions 

associated with water rights. Examples of the conditions associated with the 

water rights include consumptive use limitations or constraints on place of use, 

point of diversion, or type of use. 

Inter-Jurisdictional 

Agreements

Requires agreements among two or more jurisdictions. These jurisdictions may 

be federal agencies, state agencies, counties, municipalities, local water 

agencies, irrigation districts, industries, energy utilities, special interest groups, 

or federally recognized tribes. 

New or Revised Legislation Requires new legislation or revisions to existing legislation at either the state or 

federal level. This applies to legislation that is not already commonly 

considered to be part of the Law of the River. Examples would be legislation 

related to land use, forest management, farm programs, and water quality 

permitting.

International Agreements New agreements are required between the United States and Mexico or 

between agencies or utilities in both countries. An example would be the 

various agreements required to implement ocean desalting in Mexico and allow 

credits for Colorado River system water to be shared upstream. By implication, 

new minutes to the present international treaty may be required.

1

Law of the River includes but is not limited to the following:

Colorado River Compact, 1922

Boulder Canyon Project Act, 1928

California Seven Party Agreement, 1931

Water Treaty With Mexico, 1944

Upper Colorado River Basin Compact, 1948

Colorado River Storage Project Act, 1956

Arizona v. California Supreme Court Decree, 1964

Colorado River Basin Project Act of 1968

Criteria for the Coordinated Long Range Operation of Colorado River Reservoirs, 1970

Minute 242 of Water Treaty With Mexico, 1973
Colorado River Basin 

Water Supply and Demand Study

F3-14 December 2012

Colorado River Basin Salinity Control Act, 1974

Grand Canyon Protection Act, 1992

Colorado River Interim Surplus Guidelines, 2001

Colorado River Water Delivery Agreement, Federal Quantification Settlement Agreement, 2003

Arizona v. California Supreme Court Consolidated Decree, 2006

Record of Decision for Colorado River Interim Guidelines for Lower Basin Shortages and the Coordinated 

Operations for Lake Powell and Lake Mead, 2007

43 Code of Federal Regulations 414 Offstream Storage of Colorado River Water in the Lower Division 

States

43 Code of Federal Regulations 417 Lower Basin Water Conservation Measures

2.16 Hydropower

For the hydropower criterion, identifying potential increases or decreases in hydroelectric energy 

generation was of particular interest. The assessment was qualitative and does not replace the 

detailed CRSS modeling of Colorado River hydropower effects. 

The option submittal form asked for estimates of anticipated increases or decreases in 

hydroelectric energy generation. Information, analyses, and references provided by the option 

proponent were reviewed for accuracy and completeness. The potential impact on hydroelectric 

power generation was considered, using the submitted quantity, location, and timing information. 

The qualitative assessment considered whether new hydropower resources were included in the 

option and whether, and to what extent, implementation of the option may affect existing 

hydropower resources. 

For each proposed option, it was estimated whether the option may have: a) significantly positive 

impacts, b) moderately positive impacts, c) no impacts or impacts expected to be “neutral”, d) 

moderately negative impacts, or e) significantly negative impacts. The bins shown on the 

characterization matrix in attachment A match these categories.

2.17 Water Quality

For this criterion, changes in water quality brought about by implementation of the option were 

of particular interest. The assessment was qualitative and did not replace the detailed CRSS 

modeling of Colorado River water quality metrics.

The option submittal form asked for identification of key water quality implications (salinity and 

other constituents) associated with implementation of the option in all of the locations that the 

option might affect. Information, analyses, and references provided by the option proponent 

were reviewed for accuracy and completeness. Depending on the option and data availability, 

the water quality data provided by the option proponent were compared to data readily available 

from U.S. Geological Survey (USGS) and U.S. Environmental Protection Agency databases.

For each option, the following checklist was used to assess potential water quality impacts. 

Based on this assessment, each proposed option was assigned to one of five bins shown in the 

characterization matrix in attachment A.
Appendix F3 — Options Characterization

Criteria and Rating Descriptions

December 2012 F3-15

Water Quality Impact Items Checklist

This checklist relates only to whether the option relates to improvement or decline for the listed items. The 

extent to which specified water quality standards are being met or violated is covered separately as part of the 

evaluation of metrics.

For each checklist item, the following options are available for selection:

Significantly positive.

Moderately positive.

No significant change.

Moderately negative.

Significantly negative.

Checklist Item Description

Salinity The salinity of water added to the system or returned to the system should be 

compared to present levels to determine whether the option improves or 

degrades salinity concentrations. Present system criteria will be based on the 

closest USGS monitoring station with total dissolved solids salinity data.

Sediment Consider the potential impact the option would have on sediment transport 

through the system. Options that maintain “flushing flows” are the ones that will 

best maintain sediment transport. Also consider how conversion of land uses 

can affect sediment loadings.

Temperature Consider whether option may increase or reduce temperature of receiving 

waters. An example would be conversion of electrical energy-generating 

facilities from either once-through or recycled evaporative cooling to nonevaporative cooling with no thermal discharges to receiving waters. Another 

example is changes in reservoir release policies.

Dissolved Oxygen Consider if option increases or decreases the amount of oxygen-depleting 

substances (biochemical oxygen demand and chemical oxygen demand) 

discharged to Basin receiving waters.

Nutrients Consider if the option would change the overall nutrient balances being 

discharged to Basin receiving waters. Primary nutrients of concern are nitrogen 

and phosphorus.

Algae Consider whether the changes in nutrient discharges are likely to increase or 

decrease algal production in areas of concern. For example, any increase of 

nutrient levels in Lake Mead increases the likelihood of production of algal 

blooms that may adversely affect drinking water in Las Vegas and the 

ecosystem.

Metals Consider if the option changes the total loadings of metals discharged to the 

system.

Perchlorate Consider if the option introduces perchlorate to the system.

Emerging Contaminants Consider if the option will change the concentration or presence of potential 

emerging contaminants, such as endocrine-disrupting compounds. An example 

would be increased recycling of conventionally treated municipal wastewater 

effluent to groundwater or reservoirs that serve as sources of potable water 

supply.

Appendix F3

Attachment A

Detailed Options Characterization 

Criteria and Ratings

December 2012 F3-A-1

Attachment A — Detailed Options Characterization Criteria 

and Ratings

ATTACHMENT A

Detailed Option Characterization Criteria and Ratings 

No. Criteria Criteria Measurement

Option Characterization Rating Criteria

A B C D E

1 Quantity of Yield Average af per year > 500 > 350 > 250 > 100 < 100

2 Timing Years before option 

could begin operation

< 5 < 10 < 20 < 30 > 30

3 Cost Annual dollars per af,

Present Worth

< 500 < 1000 < 2000 < 3000 > 3000

4 Technical Feasibility 5-pt qualitative scale Regularly 

implemented in U.S. 

at scale proposed

Occasionally 

implemented 

somewhere in the 

world at similar 

scale

Regularly 

implemented but at 

smaller scales

Occasionally 

implemented 

somewhere in the 

world or has not 

been done, but peer 

review articles 

indicate promise 

Has not been done 

and no peer review 

articles exist or they 

indicate challenges

5 Implementation Risks 5-pt qualitative scale No major 

implementation risks

Some 

implementation 

risks, but risks can 

be managed

Multiple 

implementation 

risks, but may be 

managed

Multiple 

implementation 

risks, ability to 

manage risks is 

unknown

Multiple 

implementation risks 

and ability to 

manage risks is low

6 Long-term Viability 5-pt qualitative scale No major risks Some viability risks Multiple, but limited 

risks

Multiple, moderate 

risks

Multiple, significant 

risks

7 Operational Flexibility 5-pt qualitative scale Option can be 

operated/idled in 

any year with no 

financial implications

Option can be 

operated/idled in 

any year with limited 

financial implications

Option can be 

operated/idled in 

any year with 

moderate financial 

implications

Option can be 

operated/idled in 

any year with 

significant financial 

implications

Option does not 

have the flexibility to 

be operated or idled 

from year to year
Colorado River Basin 

Water Supply and Demand Study

F3-A-2 December 2012

ATTACHMENT A

Detailed Option Characterization Criteria and Ratings 

No. Criteria Criteria Measurement

Option Characterization Rating Criteria

A B C D E

8 Permitting 5-pt qualitative scale Does not require an 

EIS or other major 

permits

Requires an EIS or 

other major permits, 

but similar projects 

of this scale have 

been approved in 

the past 20 years

Requires an EIS or 

other major permits, 

but similar projects 

of smaller scale 

have been approved 

in the past 20 years

Requires an EIS and 

no precedent exists 

for the option.

Requires an EIS and 

similar options have 

been declined 

during the permit 

process

9 Energy Needs kWh/af Requires no energy, 

or results in net 

positive generation

< 1000 < 3000 < 5000 > 5000

10 Energy Source 5-pt qualitative scale No new energy 

required

Renewable energy 

sources are 

primarily used

Natural gas or "grid" 

is primary source of 

energy

Diesel fuel is 

primary source of 

energy

Coal is primary 

source of energy

11 Other Environmental 

Factors

5-pt qualitative scale Significantly positive 

impacts are likely to 

exist, and negative 

impacts are not 

readily apparent

Moderately positive 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

negative impacts of 

a lesser degree

Option does not 

have an impact or 

impacts are 

expected to be 

neutral

Moderately negative 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

positive impacts of a 

lesser degree

Significant negative 

impacts are likely to 

exist, and positive 

impacts are not 

readily apparent

12 Recreation 5-pt qualitative scale Significantly positive 

impacts are likely to 

exist, and negative 

impacts are not 

readily apparent

Moderately positive 

impacts are 

anticipated at some

locations while other 

locations may or 

may not have 

negative impacts of 

a lesser degree

Option does not 

have an impact or 

impacts are 

expected to be 

neutral

Moderately negative 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

positive impacts of a 

lesser degree

Significant negative 

impacts are likely to 

exist, and positive 

impacts are not 

readily apparent

13 Socioeconomics 5-pt qualitative scale Significantly positive 

impacts are likely to 

exist, and negative 

impacts are not 

readily apparent

Moderately positive 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

negative impacts of 

a lesser degree

Option does not 

have an impact or 

impacts are 

expected to be 

neutral

Moderately negative 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

positive impacts of a 

lesser degree

Significant negative 

impacts are likely to 

exist, and positive 

impacts are not 

readily apparent
Attachment A — Detailed Options

Characterization Criteria and Ratings 

December 2012 F3-A-3

ATTACHMENT A

Detailed Option Characterization Criteria and Ratings 

No. Criteria Criteria Measurement

Option Characterization Rating Criteria

A B C D E

14 Policy Considerations 5-pt qualitative scale Consistent with 

current local and 

federal policies

Local policies may 

require changes, but 

precedent shows 

can be publicly 

acceptable

Changes to federal 

or interstate policy is 

required but 

precedent shows 

public acceptance is 

likely

Changes to local or 

federal policy is 

required, and public 

acceptance is 

unknown

Changes to local or 

federal policy is 

required, and public 

acceptance is 

unlikely

15 Legal 5-pt qualitative scale Consistent with 

current legal 

framework

Local laws may 

require changes, but 

consistent with 

current federal legal 

framework

Federal or interstate 

legal action is 

required but 

precedent shows 

item can be 

addressed

Federal legal action 

is required, no 

precedent exists, 

and timeframe or 

likelihood of success 

is unknown

Federal legal action 

is required and 

precedent shows 

that the legal 

challenges may not 

be overcome

16 Hydropower 5-pt qualitative scale Significantly positive 

impacts are likely to 

exist, and negative 

impacts are not 

readily apparent

Moderately positive 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

negative impacts of 

a lesser degree

Option does not 

have an impact or 

impacts are 

expected to be 

neutral

Moderately negative 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

positive impacts of a 

lesser degree

Significant negative 

impacts are likely to 

exist, and positive 

impacts are not 

readily apparent

17 Water Quality 5-pt qualitative scale Significantly positive 

impacts are likely to 

exist, and negative 

impacts are not 

readily apparent

Moderately positive 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

negative impacts of 

a lesser degree

Option does not 

have an impact or 

impacts are 

expected to be 

neutral

Moderately negative 

impacts are 

anticipated at some 

locations while other 

locations may or 

may not have 

positive impacts of a 

lesser degree

Significant negative 

impacts are likely to 

exist, and positive 

impacts are not 

readily apparent.

Appendix F3

Attachment B

Methods Used for Performing 

Unit Cost Calculations

December 2012 F3-B-1

Attachment B — Methods Used for 

Performing Unit Cost Calculations

As part of the option characterization process, all submitted options were characterized using 17 

evaluation criteria that were developed by the Options and Strategies work group. The relative 

cost of an option (expressed in unit annual cost of dollars per acre-feet) was one of the 

characterization items. This unit cost was calculated by taking the present worth of all option 

costs over the study period and dividing by the annual yield of the option. More details on the 

methods used for this calculation are described below. 

Guidelines for evaluating the feasibility of water resources projects are provided in Economic 

and Environmental Principles and Guidelines for Water and Related Land Resources 

Implementation Studies (U.S. Water Resources Council, 1983). The following points summarize 

the key guidelines applicable to cost analyses:

1. Monetary values are to be expressed in average annual equivalents by appropriate 

discounting and annualizing techniques using the applicable discount rates. (section 1.7.1)

2. Monetary analyses shall consider the following (section 2.1.2):

a) Installation period – the number of years required for installation of the option.

b) Installation expenditures – the dollar expenses expected to be incurred during installation.

c) Period of analysis – Use the same period of analysis for all alternative plans. The period 

of analysis is the lesser of the period of time over which any alternative plan would have 

significant beneficial effects or 100 years.

d) Benefit stream – the pattern of expected benefits (in this case focusing on water yield) 

over the period of analysis.

e) Operation, maintenance, and replacement (OM&R) costs – the expected costs over the 

period of analysis for OM&R activities.

f) Discount rate – the rate established annually for use in evaluating federal water projects.

3. Discount any deferred installation costs and OM&R costs to the beginning of the period of 

analysis using the applicable project discount rate.

4. Guidance on the “appropriate discounting and annualizing techniques” is provided in 

Circular No. A-94 Guidelines and Discount Rates for Benefit-Cost Analysis of Federal 

Programs (Office of Management and Budget, 1992). 

5. The prescribed discount rate to be used on federal water projects is provided via the Treasury 

Annual Interest Rate Certification, table 5 – Bureau of Reclamation. For 2011, the 

prescribed discount rate for federal water projects stood at 4.125 percent.

Period of Analysis and Useful Life Duration

The Study period is from 2012 through 2060, and all the financial analyses will also be 

performed over that period. However, some options may require significant time to implement,

and the useful life of some facilities may not be over by 2060. Therefore, the estimated 
Colorado River Basin 

Water Supply and Demand Study

F3-B-2 December 2012

remaining depreciated value of the facilities will be included in the present-worth cost 

calculations when appropriate. For the Study, straight-line depreciation will be assumed and the 

useful life of key facilities will be assumed as follows:

Useful Life of Installed Facilities1

Facility

Useful Life

(years)

Plant Facilities 45

Evaporation Ponds 45

Pump Stations/Hydropower 45

Pipelines and Tunnels 60

Diversion Structures 60

Dams 75

Land 100

All other facilities / investments 45

1 Major overhaul and replacement costs for certain facility 

components such as pumps, valves, and electrical switchgear,

are included in annual OM&R costs.

References

Office of Management and Budget. 1992. Guidelines and Discount Rates for Benefit-Cost 

Analysis of Federal Programs. Memorandum for Heads of Executive Departments and 

Establishments, Circular No. A-94 Revised, October 29

U.S. Water Resources Council. 1983. Economic and Environmental Principles and Guidelines 

for Water and Related Land Resources Implementation Studies, March 10.
Appendix F3

Attachment C

Characterization Results

December 2012 F3-C-1

Attachment C — Characterization Results

Detailed characterization results for the representative options are presented in a Tableau 

workbook. Tableau is MicroSoft® Windows® software that facilitates data exploration and 

visualization. A free “reader” program is required in order to view the information. The reader 

program is available at http://www.tableausoftware.com/products/reader. 

The workbook with the characterization results is available on the compact disc that 

accompanies this report and on the Study website at

http://www.usbr.gov/lc/region/programs/crbstudy.html. 

The workbook consists of two sheets, 1) showing numeric results, where applicable (yield, 

timing, and annualized unit cost) and 2) showing the ratings (“A” through “E”) for each of the 

option characterization criteria. For the numeric results tab, option categories can be selected or 

removed by clicking their check box. For the letter ratings, option categories and criteria can be 

selected or removed by clicking their check box. The technical report and appendices include 

information on the rating criteria and rating process. Assumptions associated with individual 

ratings can be seen by either placing the mouse over that rating and hovering or by clicking on 

the individual rating. 

Appendix F4 

Option Characterization – Importation 

December 2012 F4-1 

Appendix F4 — Option Characterization – 

Importation

1.0 Introduction

River and other out-of-basin freshwater imports have been proposed to increase the overall water 

supply of the Colorado River Basin (Basin). Fourteen options related to river or other freshwater 

imports were submitted for consideration in the Colorado River Basin Water Supply and 

Demand Study (Study) and are available electronically on the compact disc accompanying this 

report and on the Bureau of Reclamation’s (Reclamation) Study website at 

http://www.usbr.gov/lc/region/programs/crbstudy.html. 

The submitted options were reviewed and organized into groups according to the location at 

which the imported water would augment the Colorado River or provide exchange water for 

regions reliant on Colorado River supplies. The submitted options were reviewed and organized 

into three groups according to the source of imported water: 

• Imports to the Colorado Front Range 

• Imports to the Green River 

• Imports to Southern California 

The general location of these options are shown in figure F4-1, with the arrow indicating the 

flow of imported water and the red square indicating the points of reduced Colorado River 

diversion. Representative options were developed for each option group to represent the distinct 

nature of the options. 
Colorado River Basin 

Water Supply and Demand Study

F4-2 December 2012

FIGURE F4-1 

Generalized Locations of Imports

This appendix summarizes the types of options received, the assumptions made, and methods 

used to characterize the options, and the characterization results. A detailed description of the 

characterization criteria, approach, and rating guidance is provided in the appendix F3. 

2.0 Imports to the Front Range

This group of options includes importing water from the Missouri River or Mississippi River to 

areas adjacent to the Basin that could use this water to meet projected shortfalls and/or reduce the 

amount of water these areas divert from the Basin. All of the Import to Front Range options 

involve large-scale diversion facilities (at least 800 cubic feet per second intake and diversion 

facilities), more than 700 miles of conveyance infrastructure spanning at least two states, and 

more than 700 megawatts (MW) of power for pumping. Water would be conveyed to the Front 

Range of Colorado and to specific areas of New Mexico and integrated into existing water 

supply systems. Although these options are termed “imports,” water would not actually be 

imported into the Basin. Rather, water would be delivered to system reservoirs serving these 

adjacent areas to reduce the amount of water exported from the upper Colorado and San Juan 

rivers.
Appendix F4 — Option

Characterization – Importation

December 2012 F4-3 

Two representative options were developed from this group of options to reflect the differences 

in potential location of diversion, conveyance infrastructure needs, and associated impacts. The 

representative options are: 

• Missouri River Imports 

• Mississippi River Imports 

Imports to the Front Range will reduce additional demand for Colorado River water beyond 

current transbasin facility yields, presumably eliminating or reducing the development of new 

transbasin facilities.

2.1 Missouri River Imports

Yield for the Missouri River concept was limited by the realistic hydraulic capacity of a single 

large-diameter pipeline. Specifically, limiting the pipe diameter to 144 inches and maintaining 

flow rates so that friction loss is less than 1 foot per thousand feet of pipe length results in a yield 

of about 600,000 acre-feet per year (afy). Because the available diversion from the Missouri 

River is not envisioned to be supply-limited to 600,000 afy, multiple parallel pipes could 

increase the quantity of yield of this option. 

The Missouri River option is a very large-scale infrastructure project, requiring more than 

700 miles of conveyance infrastructure crossing two states and more than 700 MW of power for 

pumping. Although the conveyance distance is longer than similar historical projects (Central 

Arizona Project, Colorado River Aqueduct, California State Water Project), it does use the type 

of infrastructure that has proven to be highly reliable. Therefore, confirming technical feasibility 

should not take more than 5 years. However, the permitting phase will require multi-state 

negotiations, possible permits for new power plants, and an Environmental Impact Statement as 

required by the National Environmental Policy Act. Even if the permit process were pursued 

with urgency and with political support, the process is expected to take up to 15 years. Once 

permitted, numerous design and construction crews could be mobilized to simultaneously 

construct several segments of the project. Therefore, it is possible to construct large-scale water 

transmission projects of this size in approximately 10 years. In summary, the following 

timeframe is estimated: feasibility is 5 years, permitting is 15 years, and implementation is 

estimated at 10 years, totaling 30 years. 

To estimate the cost, topographic and aerial mapping was used to select a rough alignment for 

the proposed conveyance corridor. The pumping needs were estimated based on evaluating 

topographic relief and maintaining industry-standard pressures. Once the size of the pipeline and 

number and size of the pumping stations were determined, cost database information was used to 

estimate the total capital costs. The database estimates include adjustments to estimated costs by 

considering the proposed location of the project and the scale of the project. As such, both 

location and economies of scale were considered in the capital cost estimates. Total capital costs 

were estimated to be approximately $8.6 billion. Annual costs include electricity costs for 12,000 

kilowatt hours per acre-feet (af), maintenance, repair, and replacement costs. Electricity costs 

assume that a project of this size would get favorable electricity rates due to the large and 

consistent energy demand. Specifically, a cost of $0.07 per kilowatt hour was assumed to cover 

all aspects of the energy rate. This cost is consistent with current electricity costs in the corridor 

(Black Hills Energy, 2012). The annual costs for maintenance, repair, and replacement are based 

on a percentage of the capital costs from a compiled database of information of historical costs 
Colorado River Basin 

Water Supply and Demand Study

F4-4 December 2012

for these items on similar facilities. Considering all of the above, an estimated unit annual cost 

of $1,700 per af was estimated.

In addition to yield, timing, and cost, the Missouri River importation concept was characterized 

against several other criteria. This importation option was estimated to have very high energy 

needs and high potential for permitting, legal, and policy challenges because of the project’s size, 

geographic extent, and concerns related to potential impacts in the source watersheds. The 

resulting ratings for these criteria are low. The Missouri River option would have high debt 

service costs because it is a capital-intensive project. Therefore, the option did not score well 

against the operational flexibility criteria because the high cost of debt would still be incurred if 

the project is put into an idle mode. Imports from the Missouri River would alleviate or reduce 

the need to develop additional infrastructure to divert additional water beyond current 

infrastructure yields from the Colorado River headwaters. Compared to increased Colorado 

headwater diversions, this options may improve Colorado River Basin hydropower, water 

quality, recreation, and may improve some in-basin environmental conditions. However, it is 

worth noting that it is possible that the option could introduce some adverse impacts on the same 

criteria in the basin of origin as a result of reduced flows in the Missouri River. Imports to the 

Front Range would result in water quality that would meet all drinking water standards with 

conventional water treatment, but the source water quality would be poorer than the current 

supply used by many Front Range urban purveyors. Agreement from the State of Colorado, and 

the many water providers within Colorado, would have to occur in order for this option to occur. 

Moreover, to the extent that this option would require the reduction of the amount of water that 

the state of Colorado is legally entitled to take from the Basin, this option could require an 

amendment to the Colorado River Compact of 1922 (Compact) and Upper Colorado River Basin 

Compact of 1948. 

2.2 Mississippi River Imports 

This concept is similar to the Missouri River option, but the diversion location is significantly

farther downstream along the Mississippi River system. Specifically, the proposed diversion 

location is near Memphis, Tennessee, downstream of the confluence of the Ohio River and

Mississippi River. By extending the concept to this location, the flows at the diversion location 

are significantly higher, and because the diversion location is much closer to the Gulf of Mexico, 

the potential impacts to downstream users are reduced. However, extending the concept to this 

location requires an additional 340 miles of conveyance facilities and 200 MW in pumping needs 

(increasing the estimated capital costs to $14.6 billion). With that background, the assumed 

yield of this option is identical to the Missouri River option, at 600,000 afy. The estimated unit 

annual cost is higher, at $2,400 per af. Although a larger project, the Mississippi River option is 

assumed to require the same amount of time to implement—30 years. This option was 

characterized the same as the Missouri River option on all other characterization criteria. 

Agreement from the State of Colorado, and the many water providers within Colorado, would 

have to occur in order for this option to occur. Moreover, to the extent that this option would 

require the reduction of the amount of water that entities within Colorado would take from the 

Basin to which they are legally entitled to take, this option would require an amendment to the 

Colorado River Compact and Upper Colorado River Basin Compact. 
Appendix F4 — Option

Characterization – Importation

December 2012 F4-5 

3.0 Imports to the Green River Headwaters 

This group of options includes diverting water from the upper headwaters of rivers adjacent to 

the Green River to the headwaters of the Green River. Potential sources of supply are diversions 

from the Bear River, upper Snake River1, or Yellowstone River. These potential projects 

involve intake and diversion facilities, pumping plants and conveyance facilities, and delivery to 

the Green River. Because these options are focused on headwaters-to-headwaters transbasin 

diversions, the size of the projects (in terms of magnitude of water and facilities required) are 

smaller in scale than other importation options. With the Green River headwaters concepts, the 

availability of divertible supply is the primary limiting factor, as defined in previous analyses 

prepared as part of the Colorado River Augmentation Study (Colorado River Water Consultants, 

2008). 

Three representative options were developed from this group of options to reflect the differences 

in potential location of diversion, conveyance infrastructure needs, and associated impacts. The 

representative options are: 

• Bear River Imports 

• Snake River Imports 

• Yellowstone River Imports 

3.1 Bear River Imports

Specific to the Bear River concept, the proposed diversion location is directly downstream of 

Smith’s Fork near Cokeville, Wyoming. It is worth noting that approximately 175 miles 

downstream of this location, the fresh water flows into the Great Salt Lake and is lost. Based on 

a series of relatively high-level hydrologic assessments (Colorado River Water Consultants, 

2008), a yield of 50,000 afy was estimated as potentially feasible near Smith’s Fork. For 

perspective, the Bear River at this location has historically had annual flow volumes of between 

800,000 af and 100,000 af, with an average annual flow of about 300,000 af. 

The facilities required for the Bear River option include a new river diversion, a new reservoir, 

12 miles of pipe, 2.5 miles of tunnel, and two pumping stations. This type of infrastructure has 

been proven to be reliable. Therefore, project feasibility could potentially be evaluated within a 

few years. Although the required infrastructure is technically proven, the conveyance facilities 

cross areas designated as state or national forests. Therefore, special use permits for construction 

in the public lands will be required. Also, transbasin water projects have become increasingly 

challenging to permit because of both political and environmental concerns. Therefore, at least 

7 years of permitting is anticipated. Once permitted, numerous design and construction crews 

could implement these types of projects in up to 5 years. In summary, the following timeframe 

is estimated: feasibility is 3 years, permitting is approximately 7 years, and implementation is 

approximately 5 years, totaling 15 years. 

Costs for this concept were developed by roughly sizing all of the required infrastructure 

components and then using an engineering cost estimating tool to roughly quantity the cost for 

each of the sized infrastructure components. Considering the total estimated capital cost, as well 

 

1 Among the more than 150 options submitted to Reclamation as responsive to the Plan of Study, additional importation of water supplies from 

various sources, including importation of water from the Snake and Columbia River systems, were submitted to the Study. Such options were 

appropriately reflected in the Study but did not undergo additional analysis as part of a regional or river basin plan or any plan for a specific 

Federal water resource project. This Study is not a regional or river basin plan or proposal or plan for any Federal water resource project. 
Colorado River Basin 

Water Supply and Demand Study

F4-6 December 2012

as the cost for interest, energy costs for pumping, and costs for all other required annual 

operations, maintenance, repair and replacement resulted in an estimated unit annual cost of 

$720 per af. In addition to yield, timing, and cost, the Bear River option was characterized 

against several other criteria. Key considerations related to technical feasibility, permitting, 

legal, and policy were largely covered in the descriptions above related to estimating option 

timing. The option scored low on long-term viability criteria because of its combination of risk 

from energy inflation and risk of future policy decisions that could limit diversions from the 

basin of origin. The option rates relatively poorly on operational flexibility owing to high debt 

service costs that would still exist when the option is put into an idle mode. The options would 

result in more water imported into the headwaters and therefore is anticipated to improve Basin 

hydropower, water quality, recreation, and may improve some in-basin environmental 

conditions. However, there are also potential adverse impacts to the Bear River basin due to 

reduced flows. Without extensive and detailed study, it is not possible to ascertain if the benefits 

to the Basin would be greater than or less than the adverse impacts to the basin of origin. At this

time, neutral overall impacts are assumed for recreation and hydropower. Because the diversion 

would reduce Bear River flows through the Great Salt Lake Delta and the Bear River Migratory 

Bird Refuge, this option was characterized slightly lower than similar Green River Imports 

options. 

3.2 Snake River Imports

According to the Snake River Interstate Compact (Snake River Compact, 1949), Wyoming has 

rights to deplete 4 percent of the annual flow in the Snake River at the state line. The first 2 

percent of that water can be directly diverted, but diversions of more than 2 percent require 

storage along the river to assist in the management of potential impacts to Wyoming diversions. 

For this reason, 33,000 af of storage along the Snake River in the Palisades Reservoir has been

allocated to Wyoming. This option investigates using Wyoming rights to divert 33,000 afy from 

the Snake River during high-flow periods and store that water in Palisades Reservoir. Then the 

water would be pumped through 26 miles of pipe and 6 miles of tunnel into the headwaters of the 

Green River Basin. The estimated yield for this option is 33,000 afy. 

In regards to timing, Wyoming has the water rights to divert and use this water. However, 

because the proposed water use is related to a transbasin diversion, approval by the State of 

Idaho is required by Article 4 of the Snake River Compact. Therefore, it is assumed that this 

option could not be implemented any faster than the Bear River option. Specifically, 3 years of 

feasibility, 7 years of permitting and interstate negotiations, and 5 years of construction, totaling 

15 years, would be required. 

In regards to costs, this option would require approximately $200 million in new pumping and 

conveyance facilities, and when factoring in energy costs and all other required annual 

operations and maintenance costs, the resulting unit annual cost is estimated to be about $800 per 

af. 

Compared to the Bear River importation option, the Snake River option received slightly better 

ratings for permitting and other environmental factors because a new reservoir is not required for 

this option. However, the Snake River option received a slightly lower rating on legal criteria 

attributable to potential complexities related to agreements with Idaho and the Snake River 

Compact.
Appendix F4 — Option

Characterization – Importation

December 2012 F4-7 

3.3 Yellowstone River Imports 

Wyoming is allocated 60 percent of the depletable yield of the Clark’s Fork of the Yellowstone 

River. According to the 1973 Wyoming Framework Water Plan (Wyoming State Engineer’s 

Office, 1973), Wyoming’s 60 percent allocation is 428,000 af in an average year. Currently, 

very little water is depleted from this river basin. However, it is also worth noting that this river 

has been designated wild and scenic, which could affect the ability to obtain diversion permits. 

The proposed option is for 75,000 afy (or 20 percent of Wyoming’s depletable allocation). The 

option includes diverting water from Clark’s Fork near the Wyoming state line and conveying 

the water approximately 45 miles to the Buffalo Bill Reservoir, where pumps, pipes, and tunnels 

would be used to convey the water an additional 90 miles to the Green River Basin. 

In regards to timing, the proposed technology is well-proven, and a technical feasibility study 

could be completed in less than 3 years. However, the permitting and negotiations with the 

downstream state (Montana) would likely take at least 7 years. If permitted, the projects could 

be constructed over a 5-year duration. 

In regards to cost, this option includes a considerably longer alignment than the other imports to 

the headwaters of the Green River options, and the cost is reflective of the longer length with an 

estimated unit annual cost of $1,900 per af. For the same reason, the energy needs of this option 

are slightly higher than other Green River imports options. 

In regards to other characterization criteria, this option was characterized almost identically to 

the Snake River imports options because of the general similarities of the options.

4.0 Imports to Southern California

This group of options is focused on importing high-quality water from other regions using ocean 

routes to Southern California coastal areas. Potential sources of water include the Columbia2

River, rivers in Alaska, or icebergs. Delivery mechanisms include sub-ocean pipelines for 

Columbia River supplies, tanker ships for Alaskan river supplies, or tug boats for icebergs. All 

of the options in this group require extensive transport or conveyance of water from the source 

regions to Southern California and require relatively complex facilities and operations to 

integrate the supply within the current water supply system in Southern California. 

Four representative options were developed from this group of options to reflect the differences 

in potential location of imported water, modes of transport and conveyance, and associated 

impacts. The representative options are: 

• Columbia River Imports 

• Icebergs

• Tankers

• Water Bags

 

2 Among the more than 150 options submitted to Reclamation as responsive to the Plan of Study, additional importation of water supplies from 

various sources, including importation of water from the Snake and Columbia River systems, were submitted to the Study. Such options were 

appropriately reflected in the Study but did not undergo additional analysis as part of a regional or river basin plan or any plan for a specific 

Federal water resource project. This Study is not a regional or river basin plan or proposal or plan for any Federal water resource project. 
Colorado River Basin 

Water Supply and Demand Study

F4-8 December 2012

4.1 Columbia River Imports

This concept includes constructing a diversion structure near the mouth of the Columbia River, 

which would feed a sub-ocean pipeline that would travel along the coast to Southern California 

before turning inland to deliver water to the local Southern California water infrastructure 

system. The availability of supply for locations such as the mouth of the Columbia River was 

not estimated to be the limiting factor. For this group of options, the limiting factor is based on 

the capacity and configuration of existing infrastructure in Southern California. Integrating large 

quantities of new supply to offset Colorado River diversions would be difficult due to 

infrastructure constraints. Although the exact integration limit is difficult to quantify, 

600,000 afy was estimated based on rough estimates of integration capability. This volume is 

coincidentally consistent with other large-scale import options and therefore provides some 

degree of comparability to other import options. 

The time required to implement this type of option is highly uncertain. This is because subocean pipelines of the proposed size and length are largely unprecedented. Therefore, the 

feasibility phase is assumed to take at least 10 years and may require some pilot testing of subocean pipeline designs. The permitting phase may also take 10 years to conduct interstate

negotiations and the need to complete an environmental impact statement. Finally, construction 

of more than 1,000 miles of 144-inch sub-ocean pipeline across large submarine canyons could 

take up to 20 years. All combined, the timing for this option is assumed to be 40 years. 

The cost of this option is also highly uncertain. The costs available on this option are dated and 

are presented on a dollar-per-af basis without sufficient explanation as to how the unit cost was 

calculated (Reclamation, 1971). By updating past Reclamation costs from 1971 estimates and 

making adjustments for considering a smaller-scale concept than the one considered in 1971, this 

option is roughly estimated to have a unit annual cost of at least $3,400 per af. 

In addition to timing and cost, this option did not rate for any of the other characterization 

criteria except water quality due to difficult feasibility, permitting challenges, and unknown 

environmental impacts. Only water quality was rated higher due to the importation of better 

water quality from the Columbia River than the existing Colorado River supply. 

4.2 Imports via Icebergs 

This concept includes wrapping large water bags around icebergs in the Alaska region and using 

tug boats to transport the frozen water to a port along the coast of Southern California. As the 

water melts in the water bags, the water would then be pumped to a transfer station at the port 

and then pumped and piped to locations such as Diamond Valley Lake for treatment and 

consumption. A small iceberg contains 250 to 850 af. Assuming approximately one iceberg 

transported per day, this would yield approximately 200,000 afy. 

In regards to timing, this option would require the construction of a new terminal similar to the 

design of an oil-receiving terminal at a sea port. Next, pipes and pumps would need to be 

permitted from the port to the targeted receiving lake (assumed to be Diamond Valley Lake). 

Based on these considerations, this option is assumed to take at least 10 years for feasibility, 

5 years in permitting, and 5 years in construction, totaling at least 20 years. Because this type of 

project would most likely be completed in phases, additional phases are assumed to require 

another 10 years to complete.
Appendix F4 — Option

Characterization – Importation

December 2012 F4-9 

In regards to cost, assumed costs to lease very large tug boats were developed through research 

of existing industry practices. These include the cost of the boat, crew, and fuel. The cost to 

construct a new terminal at an existing port near Los Angeles was estimated based on recent 

studies to build a new oil terminal in Los Angeles (Los Angeles Economic Development 

Corporation, 2008). The cost to build pipelines and pump stations from the port to Diamond 

Valley Lake were based on the cost of previously completed pipelines and pumping stations in 

this region. The resulting capital costs were estimated to be approximately $3.5 billion. Based 

on all of these considerations, the estimated unit annual costs are $2,700 per af. 

In regards to other characterization criteria, this option requires significant amounts of fuel and 

therefore the rating for energy needs is low. Also, the rating for long-term viability is low 

because of the risk that escalating fuel prices could further increase the cost of this option. 

4.3 Imports via Tankers

The tanker option is very similar to the iceberg option. Large tanker ships would be used to 

accept water in a port near a river in Alaska and deliver the water to the same type of port in 

Southern California that was described in the iceberg option. Large tankers could have 

capacities of 276 to 445 af (Ocean Shipping Consultants, 2007). Maximum annual yield of 

600,000 af is again assumed to be limited by the existing distribution system. The same 

integration infrastructure is required from the Southern California port to a lake such as Diamond 

Valley Lake. Owing to the need for larger ships and a second port in the exporting basin, the 

costs may be slightly higher than the iceberg concept. However, developing and utilizing water 

bags would not be required. A rough estimate of the unit annual cost of this option is $2,900 per 

af. In regards to yield, timing, and all other characterization criteria, the option characterizes

exactly the same as towing icebergs. Characterization of this option was performed as increments 

of 200,000 afy in order to capture issues of scale and other complexities of large-scale programs.

4.4 Imports via Water Bags 

This option is exactly the same as the tankers option, but except instead of using tankers, the 

option focuses on capturing fresh water near the mouth of several large rivers in Alaska. Water 

bags are expected to have capacities of about 40 af. This option is assumed to characterize 

exactly the same as tankers. 

5.0 Characterization Results 

A summary of the characterization findings are shown in table F4-1. The top portion of the table 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the table shows the 17 criteria and associated ratings (“A” through “E”) and is 

color-scaled. In general, “C” is typically designated as mostly neutral; “A” is largely positive; 

and “E” is largely negative. Refer to appendix F3 for specific criteria descriptions and rating 

scales.

Notes providing detailed justification for each option criteria rating are available in electronic 

form on the accompanying compact disc and on Reclamation’s website at 

http://www.usbr.gov/lc/region/programs/crbstudy.html. 
Colorado River Basin 

Water Supply and Demand Study

F4-10 December 2012

TABLE F4-1 

Summary Characterization Ratings for Importation Options
Appendix F4 — Option

Characterization – Importation

December 2012 F4-11

6.0 References 

Black Hills Energy Corporation. 2012. Schedule of Rates for Electrical Service, Large 

Industrial Customer, Transmission Rate Class. 

Bureau of Reclamation (Reclamation). 1971. Study Work Plan for California Undersea 

Aqueduct, Reconnaissance Investigation, Working Document. September. 

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for 

the Water Supply of the Colorado River System. 

Los Angeles Economic Development Corporation. 2008. Crude Oil Marine Terminal at the 

Port of Los Angeles Economic Impact Study. 

Ocean Shipping Consultants, 2007. The Tanker Market, Mixed Outlook Ahead

Snake River Compact. 1949. Available at: 

http://waterplan.state.wy.us/BAG/snake/briefbook/ss_compact.htmlref 

Wyoming State Engineer’s Office. 1973. The Wyoming Framework Water Plan. May. 
Appendix F5 

Option Characterization – Desalination

December 2012 F5-1 

Appendix F5 — Option Characterization – 

Desalination

1.0 Introduction

Ocean and brackish water desalination has been proposed to increase the supply in those areas 

currently relying upon water supply from the Colorado River. A number of desalination options 

were submitted for consideration in the Colorado River Basin Water Supply and Demand Study 

(Study). The submittals are summarized in appendix F2 and the original submittals are available 

via links from the electronic version of appendix F2 on the compact disc that accompanies this 

report and the version of appendix F2 on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

15 options were submitted related to ocean or brackish water desalination. Some of the 

submittals were related to specific projects with detailed descriptions, while others were 

provided as general concepts. The submitted options were reviewed and organized into groups 

according to the source of the desalination water: 

• Ocean Desalination

• Desalination of Agricultural Drainwater

• Desalination of Brackish Groundwater 

The general location of these options are shown in figure F5-1,with the arrow indicating the flow 

of desalinated water and the red square indicating the points of reduced Colorado River 

diversion. Representative options were developed for each option group to represent the distinct 

nature of the options. 

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Additional detail related to the 

options characterization is included in appendix F3. Attachment A of appendix F3 contains more 

detailed descriptions of the ratings. Attachment B provides the methods used for completing the 

unit cost calculations. Attachment C presents the detailed characterization information and is 

available on the compact disc that accompanies this report and on the Study website.
Colorado River Basin

Water Supply and Demand Study

F5-2 December 2012

FIGURE F5-1 

General Locations of Desalination Options

2.0 Ocean Desalination 

This group of options consists of constructing new ocean desalination plants in strategic 

locations along the Southern California coast or near the international boundary in Mexico. The 

desalinated water would be delivered to some of the larger existing operational reservoirs in the 

Metropolitan Water District of Southern California (MWD) system or similar reservoirs in 

MWD member agencies’ systems. This option group also includes constructing new ocean 

desalination plants along the Gulf of California (Gulf) in the United Mexican States (Mexico). 

This desalinated water would be delivered to Imperial Dam north of the international boundary, 

where the water could be left in the river to meet water commitments to Mexico or diverted into 

the All American Canal. For both the Pacific Ocean and the Gulf desalination plants, the water 

could be exchanged to Lake Havasu or higher up the river to Lake Mead or Lake Powell, thereby 

allowing the new supply to benefit water users up and down the river. 
Appendix F5 — Option

Characterization – Desalination

December 2012 F5-3 

Three representative options were developed from this group of options to reflect the various 

potential desalination plant locations. The representative options consist of the following: 

• Pacific Ocean Desalination in California

• Pacific Ocean Desalination in Mexico

• Gulf of California Desalination

2.1 Pacific Ocean Desalination in California

The quantity of yield for this concept is limited by the ability to integrate the new supply into the 

proposed delivery points or by the hydraulic capacity limitations of a single large pipeline. 

Based on discussions with MWD, Pacific Ocean desalination concepts are estimated to be 

limited to 600,000 acre-feet per year (afy) due to integration considerations. 

With regard to timing, the Pacific Ocean projects would require well over 20 California and 

federal permits. California permits such as those from the Coastal Commission, State Lands 

Commission, Regional Water Quality Control Boards, and Department of Public Health can be 

challenging to obtain and may affect the viability and/or cost and timing of the particular project. 

This would be especially true for the potential sizing and transfer components of the proposed 

projects. It is roughly estimated that 200 million gallons per day (200,000 afy) of Pacific Ocean 

projects could require 5 years of feasibility, 10 years of permitting, and 5 years of 

implementation, totaling 20 years. 

Several recent studies have included cost estimates for ocean desalination facilities. The 2008 

augmentation study included planning-level cost estimates for facilities in Southern California, 

Baja California, and along the Gulf (Colorado River Water Consultants, 2008). In addition to the 

information available from these studies, water treatment plant conceptual design and cost 

estimating tools were used to estimate treatment costs, including intake and outfall facility costs. 

A cost estimating tool was also used to estimate costs of the pipelines and pump stations that 

would convey the water from the coast to the selected delivery location. Total capital costs were 

estimated to range from $2.8 to $3.2 billion depending on location. Annual costs include 

electricity, chemicals, maintenance, repair, and replacement costs. Electricity costs assume that 

a project of this size would get favorable electricity rates because of its large and consistent 

energy demand. Specifically, a cost of $0.10 per kilowatt hour was assumed to cover all aspects 

of the energy rate. This cost is consistent with current assumptions on electricity costs for ocean 

desalination plants in the Southern California region (HDR Inc., 2009). The annual costs for 

maintenance, repair, and replacement are based on a percentage of the capital. With all these 

considerations accounted, the annual cost per acre-foot (af) of produced water is estimated to be 

approximately $1,900 per af, with a range between $1,600 per af and $2,600 per af, assuming 

200,000 afy construction increments and 50 miles between the plant and delivery location. 

In regard to technical feasibility, ocean desalination facilities have been completed in numerous 

locations around the world, but none at the scale described for the larger supply concepts. 

Therefore, technical feasibility characterization varies based on scale and precedence for similar 

options. When considering long-term viability, there is some concern about the potential for 

increased electricity costs to affect viability. Potential environmental impacts have been the key 

focus of the regulatory agencies. The main barriers to larger-scale desalination in California 

have been attributable to concerns regarding: impingement and entrainment at seawater intakes, 

hyper-saline impacts from brine discharge a planned Ocean Plan amendment to address these 

impacts currently under development by the California State Water Resources Control Board
Colorado River Basin

Water Supply and Demand Study

F5-4 December 2012

with anticipated completion by late 2013, limitations from implementation of coastal Marine 

Protected Areas, areas of Special Biological Significance, and phase-out of once-through cooling 

intake/outfall use at coastal power plants. These concerns will contribute to permitting and 

implementation challenges.

None of the desalination options rate high for operational flexibility criteria because these 

options would have high debt service costs that exist even when the option is put into an idle 

mode. All of the desalination options have relatively high energy requirements. When 

considering hydropower, recreation, and other environmental impacts, many of these options rely 

on exchanges along the river to varying degrees, which could result in a change in how the river 

reaches are operated and could have adverse impacts due to reduced releases or river flows. In 

regard to water quality, some options have the potential to have a positive impact by reducing 

salinity levels in specific locations. Socioeconomic impacts are difficult to fully assess because 

jobs will be created with all of these options, but there is also likely to be a combination of 

positive and adverse impacts when considering factors beyond simply job creation (e.g., effects 

on communities). Without more-detailed assessments, neutral conditions were assumed for 

socioeconomics. 

2.2 Pacific Ocean Desalination in Mexico

This concept consists of constructing a desalination plant adjacent to a power plant in Rosarito, 

Mexico. Quantity of yield for this concept is limited by the ability to integrate the new supply 

into the regional infrastructure in the San Diego region as well as site constraint considerations. 

The largest plant size considered to date is 75,000 afy. With regard to timing, feasibility studies 

have been completed (San Diego County Water Authority, 2010) and additional studies are 

underway. Permit requirements are similar but possibly not quite as challenging or timeconsuming as constructing similar facilities in California. It is roughly estimated that a 

56,000 afy plant at this location could require 10 years of permitting, and 5 years of 

implementation, totaling 15 years. Costs and energy requirements are relatively consistent with 

the similar Pacific Ocean desalination concepts evaluated for California. This type of option is 

smaller than some of the other ocean desalination options, and so the criteria related to impact to 

the Colorado River, including hydropower impacts, recreation impacts, and ecological impacts, 

all have ratings that are slightly negative, but more favorable than the larger-scale options. 

2.3 Gulf of California Desalination

The Gulf desalination concepts are assumed to be limited to 600,000 afy of increased supply, 

based on the hydraulic capacity constraints of a single large-diameter pipeline. However, if 

parallel pipelines were installed, larger yields are feasible.

The Gulf projects would require international negotiations and potential mitigation measures that 

may lengthen the permitting and implementation process. It is estimated that the Mexico options 

would require the same time for permitting and implementation as the Pacific Ocean projects—

roughly 20 years. This assumption considers that feasibility studies have already begun for this 

representative option. 

The same sources of information and cost estimating assumptions were used for the Gulf 

desalination option as for the Pacific Ocean option. Additionally, a more-detailed cost study on 

ocean desalination concepts in the Gulf completed in 2009 (HDR Inc., 2009) was referenced. 

Based on these references, the annual cost of produced water is estimated to be approximately 
Appendix F5 — Option

Characterization – Desalination

December 2012 F5-5 

$2,100 per af. These costs are based on assumptions of 200,000 afy construction increments and 

considering that approximately 170 miles of conveyance facilities are required to deliver the 

desalinated water from the Gulf coast to Imperial Dam. The resulting estimate for capital costs is 

approximately $4.2 billion. When comparing costs to the Pacific Ocean option, the additional 

cost is associated with the location of the projects and the assumed points of delivery, which 

involve longer conveyance facilities. 

Other key considerations used to characterize the Gulf desalination option were the same as the 

Pacific Ocean option.

3.0 Desalination of Agricultural Drainwater 

This group of options consists of constructing new diversions upstream of the Salton Sea that 

would capture agricultural drainage water and deliver this water to a regional brackish water 

desalination facility. The desalinated water would be delivered back to the All American Canal 

upstream of the East Highline Canal, allowing the water to be delivered to Imperial Irrigation 

District and by exchange, Coachella Valley Water District customers who rely on the All 

American Canal system. Simultaneously, an in-kind reduction in diversions is possible from the 

river at Imperial Dam.

In this case, only one representative option was used—Salton Sea Drainwater Reuse. 

3.1 Salton Sea Drainwater Reuse

The quantity of additional yield for this representative option is limited to the amount of 

agricultural drainage water entering the Salton Sea through the New and Alamo rivers and direct 

agricultural drainage, and limitations of maintaining the Salton Sea system. Between 300,000 

afy and 500,000 afy of sustainable yield was assumed.

This concept changes the flow balance in the Salton Sea, so substantial time would be needed to 

obtain permits from the California State Water Resources Control Board, and several other

permitting entities in California. Impacts of reduced Salton Sea inflows associated with 

implementation of the Quantification Settlement Agreement (QSA) have been addressed in 

environmental documentation prepared prior to execution of the QSA. Consistency with the 

QSA would need to be evaluated, and mitigation for air quality impacts of increased exposed 

Salton Sea playa would be required. Although these efforts would take time, it is assumed that 

the option could be done with 5 years of feasibility, 5 years of permitting, and 5 years of 

implementation, totaling 15 years. 

The cost of this option is highly dependent on the assumed salinity concentration of the 

agricultural drainwater and the method of disposing of the brine stream from the reverse osmosis 

units. The option recommends using a salinity of 2,500 milligrams per liter (mg/L) for the 

drainwater and 700 mg/L for the product water to ensure similar or improved water quality for 

those dependent on the source. Based on this level of salt removal, the size and cost of the 

treatment plant can be estimated. Also, it is assumed that the brine stream would be of lower salt 

concentration than the Salton Sea (currently higher than 45,000 mg/L) and therefore could be 

discharged to the sea. Once these parameters were selected, the same cost tools used to estimate 

ocean desalination concepts were used to estimate capital costs (approximately $2.1 billion) as 

well as electricity, chemicals, maintenance, repair, and replacement annual costs for the 
Colorado River Basin

Water Supply and Demand Study

F5-6 December 2012

agricultural drainwater concepts. Based on these assumptions, the cost of produced water is 

estimated to be approximately $950 per af assuming 200,000 afy construction increments. 

In addition to yield, timing, and cost, the Salton Sea drainwater reuse option was characterized 

for several other criteria. Key considerations related to technical feasibility, permitting, legal, 

and policy issues were largely covered in the descriptions above related to estimating option 

timing. In regard to technical feasibility, desalination of agricultural drainwater has been 

accomplished in numerous locations around the world, but none at the scale described herein. 

Therefore, the technical feasibility characterization varies based on scale and precedence for 

similar options. When considering long-term viability, there is some concern about the potential 

for increased electricity costs to affect viability. The option does not rate high for operational 

flexibility criteria because it would have high debt service costs even when the option is put into 

an idle mode. Desalination of agricultural drainwater involves relatively high energy 

requirements as well. When considering hydropower, recreation, and other environmental 

impacts, the option relies on exchanges along the river to varying degrees, which could result in 

a change in how the lower river reaches are operated and could have adverse impacts. 

Socioeconomic impacts are difficult to fully assess because jobs will be created with all of these 

options, but there is also likely to be a combination of positive and negative impacts when 

considering more than just job creation. Without more-detailed assessments, neutral conditions 

were assumed for socioeconomics.

4.0 Desalination of Brackish Groundwater

This group of options consists of completing relatively small local projects by municipal water 

providers in Southern California consistent with past similar projects. This group also includes 

refurbishing the Yuma Desalting Plant back to full-scale production. 

Two representative options were developed for this group of options to reflect the differences in 

potential location of diversion, conveyance infrastructure needs, and associated impacts. The 

representative options are: 

• Southern California Groundwater Desalination 

• Brackish Water Desalination in the Yuma Area

4.1 Southern California Groundwater Desalination

This representative option is limited by sustainable groundwater extraction rates, sustainable 

brine disposal capabilities, or the capacity of existing facilities. Without updating past studies, it 

is difficult to calculate the amount of remaining sustainable brackish groundwater yield in 

Southern California. However, a large number of previously identified projects have been 

implemented, and a rough estimate is that 20,000 afy of additional sustainable yield remains. 

With regard to time required to produce desalinated brackish groundwater, groundwater 

extraction and treatment are proven concepts. Therefore, the timing for projects in this 

representative option is limited to 5 years of permitting and 5 years of implementation, totaling 

10 years. 

Similar to the agricultural drainwater option, the cost of this option is highly dependent on the 

assumed salinity concentration of the extracted groundwater and the method of disposing of the 

brine stream from the reverse osmosis units. This option was submitted as a general concept for 

Southern California, without designation of a specific groundwater source in a specific location. 
Appendix F5 — Option

Characterization – Desalination

December 2012 F5-7 

Therefore, it is not possible to accurately estimate the salinity of the source water or the options 

for brine discharge. Assuming the source water has a salinity concentration of 1,500 mg/L 

(approximate groundwater total dissolved solids), production water is treated to 350 mg/L, and 

the resulting brine can be disposed of locally, capital costs are estimated to be approximately 

$80 million and produced water is estimated to have a unit annual cost of between $600 and 

$700 per af. 

Key considerations related to technical feasibility, permitting, legal, and policy were largely 

covered in the descriptions above related to estimating option timing. In regard to technical 

feasibility, groundwater desalination facilities have been completed in numerous locations 

around the world. When considering long-term viability, there is some concern about the 

potential for increased electricity costs to affect viability. Operational flexibility was 

characterized as low because the option would have debt service costs even when the option is 

put into an idle mode. Like the other desalination options, groundwater desalination has 

relatively high energy requirements, although fewer requirements than seawater desalination. 

When considering hydropower, recreation, and other environmental impacts, water exchanges

could result in a change in how the lower river reaches are operated and could have adverse 

impacts. In regard to water quality, some options have the potential to have a significant positive 

impact in reducing salinity levels in specific locations. Socioeconomic impacts are difficult to 

fully assess because jobs will be created with all of these options, but there is also likely to be a 

combination of positive and adverse impacts when considering more than just job creation. 

Without more-detailed assessments, neutral conditions were assumed for socioeconomics.

4.2 Brackish Water Desalination in the Yuma Area

The yield of brackish groundwater in the vicinity of Yuma, Arizona, is limited to 100,000 afy by 

the available capacity of the Yuma Desalting Plant.

The major challenge for full-scale operation of the Yuma Desalting Plant is minimizing the 

impact to the Cienega de Santa Clara. In lieu of using Wellton-Mohawk Irrigation and Drainage 

District drainage water, saline Yuma Mesa groundwater could be considered as source water for 

the plant. A recent 9-month pilot run at one-third capacity utilizing this drainage water produced 

promising results (Reclamation, 2012). Therefore, the timing for this option is limited to 5 years 

of permitting and 5 years of implementation, totaling 10 years. 

For full-scale operation of the Yuma Desalting Plant, the brackish groundwater is known to have 

a total dissolved solids concentration of about 1,500 parts per million, and disposal of the waste 

brines would be to the Gulf via the Main Outlet Drain Extension. The unit annual cost of 

produced water is estimated at $640 per af. 

Other key considerations were similar to the other desalination options. 

5.0 Characterization Results 

A summary of the characterization findings are shown in table F5-1. The top portion of the table 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the table shows the 17 criteria and associated ratings (“A” through “E”) and is

color-scaled. In general, “C” is typically designated as mostly neutral; “A” is largely positive; 

and “E” is largely negative. Refer to appendix F3 for specific criteria descriptions and rating 

scales.
Colorado River Basin

Water Supply and Demand Study

F5-8 December 2012

TABLE F5-1 

Summary Characterization Ratings for Desalination Options
Appendix F5 — Option

Characterization – Desalination

December 2012 F5-9 

6.0 References 

Bureau of Reclamation (Reclamation). 2012. Yuma Desalting Plant Pilot Run Final Report.

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for 

the Water Supply of the Colorado River System. 

HDR Inc. 2009. Investigation of Binational Desalination for the Benefit of Arizona, United 

States, and Sonora, Mexico. 

San Diego County Water Authority. 2010. Final Report, Rosarito Beach Binational 

Desalination Plant Feasibility Evaluation and Preliminary Design, Phase I. 
Appendix F6

Option Characterization – Reuse

December 2012 F6-1

Appendix F6 — Option Characterization –

Reuse

1.0 Introduction

Many municipal and industrial entities that receive Colorado River water have implemented 

wastewater reuse programs and have plans to develop additional supply through future reuse. 

Development of reuse above current plans has been proposed to provide a “new” supply in those 

areas currently relying upon water supply from the Colorado River. A number of reuse options 

were submitted for consideration in the Colorado River Basin Water Supply and Demand Study 

(Study).The submittals are summarized in appendix F2 and the original submittals are available 

via links from the electronic version of appendix F2 on the compact disc that accompanies this 

report and the version of appendix F2 on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html.

Eleven options were submitted related to reuse to increase the supply the Study area. Many of 

these submittals were related to specific reuse programs, specific uses of reuse water, or 

geographic-specific reuse opportunities. The major areas of potential reuse are shown in 

figure F6-1.

Due to the large number of geographic specific approaches and limitations, a set of Colorado 

River Basin (Basin)-wide option groups and representative options were developed based on the 

type of reuse: 

Municipal Wastewater Reuse 

Industrial Wastewater Reuse 

Grey Water Recycling

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Additional detail related to the 

options characterization is included in appendix F3. Attachment A of appendix F3 contains more 

detailed descriptions of the ratings. Attachment B provides the methods used for completing the 

unit cost calculations. Attachment C presents the detailed characterization information and is 

available on the compact disc that accompanies this report and on the Study website.

For each type of reuse, the option was only considered to provide new supply to the adjacent 

areas or areas where return flow does not augment Colorado River flow. This consideration was 

due to the balance between diversions, consumptive use, and return flow within the hydrologic 

basin that results in most return flows becoming available for downstream purposes.

In addition, states such as Colorado, Wyoming, and New Mexico have regulatory frameworks 

that dedicate return flows to other users or require return flow for water rights purposes. In these 

states, the potential for reuse was limited by these downstream return flow considerations. In 

other areas, such as Southern California, physical infrastructure capacity limited the amount of 

reuse that could be effectively developed.
Colorado River Basin 

Water Supply and Demand Study

F6-2 December 2012

Implementation of additional reuse programs helps meet local demands in the Study Area. The 

areas of greatest potential for reuse exist outside of the hydrologic basin and generally include a 

portfolio of water supplies (groundwater, local supplies, other imports), including Colorado 

River water. These supplies each have their own cost, reliability, water quality, and other factors 

that lead to agency preferences related to which supply (current or future) would be reduced 

under lower demand scenarios. Under purely financial considerations, it is unlikely that the 

Colorado River supply is the marginal supply in the portfolio. Given the complexity of regional 

and local water management decisions, it was simply assumed that increased development of 

reuse reduces water demands proportionally to the magnitude of supply from Colorado River and 

non-Colorado River sources. However, because these demand reductions benefit more than just 

Colorado River water users, the cost of achieving these reductions is assumed to be shared by the 

beneficiaries. Figure F6-1 shows the primary reuse locations.

FIGURE F6-1

Areas of Significant Potential Reuse

2.0 Municipal Wastewater Reuse

Nine of the options propose reusing potentially available municipal wastewater to varying 

degrees. Concepts related to reuse of municipal wastewater in major urban areas were 

considered for either non-potable purposes such as irrigation or for potable purposes through 

indirect or direct methods. 
Appendix F6 — Option

Characterization – Reuse

December 2012 F6-3

One representative Basin-wide option was developed for this group, but includes regional 

differentiations related to types of reuse. For example, non-potable reuse was considered in all 

major municipal areas receiving Colorado River water. However, indirect potable reuse was 

considered for areas in Southern California and Arizona due to the current and already planned 

high levels of non-potable reuse programs. The municipal reuse representative option includes 

reuse for parks, golf courses and other traditional municipal uses. When potential yield of a 

representative option exceeds 200 kafy, the representative option was characterized in 

progressive 200 kafy “steps” to represent likely project phasing.

2.1 Non-potable Reuse in California, Colorado, Utah, Arizona, New Mexico, 

and Wyoming

The potential for traditional non-potable reuse (providing treated wastewater for landscape 

irrigation) for golf courses, parks, and industry was evaluated for California, Colorado, Utah, 

Arizona, New Mexico, and Wyoming. Golf course demand was assessed based on the typical

number of golf courses per person, with a typical number of acres per course and local 

evapotranspiration. About 37 percent of existing courses are supplied with reuse water, resulting 

in an additional potential non-potable reuse demand of about 275,000 acre-feet (af). This 

potentially overlaps to some extent with the broader municipal systems considered below. 

As noted above, reuse potential in Colorado, New Mexico, and Wyoming is limited by 

regulatory considerations. These states were assumed to have a reuse potential of about 

80,000 af. This amount of reuse was derived from estimates of additional reuse potential in 

Colorado (CWCB, 2010), conversations with Wyoming water managers, and direct experience 

with assessing reuse potential in New Mexico. Reuse in Utah was limited by the total diversion 

out of the hydrologic basin to the Wasatch Front of 20,000 af (i.e., the potential reuse supply is 

greater, but this is the maximum benefit to the Basin). Arizona was estimated to have a reuse 

potential of about 250,000 af based on information provided by the Arizona Department of 

Water Resources. Because of infrastructure limitations, California was estimated to have a total 

reuse potential of 600,000 af. For both Arizona and California, it was assumed that of these 

totals about one third could be applied for non-potable reuse, with the remaining amount 

available for indirect or direct potable reuse. Overall, traditional non-potable reuse potential was 

assumed to be about 360,000 af.

Because traditional non-potable reuse is commonly practiced in the Southwest, these options 

were assumed to require about 3 years for feasibility, 2 years for permitting, and 5 years for 

implementation, for a total of 10 years. 

Unit annual costs for traditional non-potable uses were derived from the augmentation study 

(Colorado River Water Consultants, 2008) at about $1,500 per af. 

In addition to yield, timing, and cost, the non-potable reuse option was characterized using 

several other criteria. A summary of the findings for all criteria is shown in table F6-1. Nonpotable projects of this size have not been implemented in the Study Area previously. 

Permitting, legal, and policy implementation will be more difficult for the indirect potable option 

than for more-traditional non-potable reuse. There is some implementation risk due to the 

amount of capital required. There is also some risk of infrastructure failure and risk of escalating 

costs because of the energy-intensive nature of the options. The option scores poorly under 

operational flexibility as a result of the likely associated debt service for a stranded asset. 

Energy needs are estimated at 500 kilowatt hours (KWh) per af. This energy would come from 
Colorado River Basin 

Water Supply and Demand Study

F6-4 December 2012

the grid resulting in a mix of fuel sources. If the option resulted in fewer releases to the Lower 

Basin, due to a reduction in demand for Colorado River water, then hydropower would be 

reduced. This effect would be most notable for larger implementations. The non-potable option 

could increase salinity in the Basin because salts are not discharged with the wastewater. 

Recreation impacts are largely neutral. If the demand for Colorado River water is reduced,

resulting in higher streamflows, the effect would be largely positive toward the “other” 

environmental factors, but disposal in inland areas may be environmentally challenging and there 

may be some localized long-term effects related to ocean brine disposal for larger 

implementations. No appreciable positive or negative impacts to socioeconomics are noted.

2.2 Indirect Potable Reuse in Southern California and Arizona

In California and Arizona, indirect potable reuse was assumed as the most likely method of reuse 

for most reuse beyond that which is already included in demand scenarios. Indirect potable reuse 

supply can be re-introduced into municipal water supply reservoirs or groundwater basins, 

blended with other supply sources, treated, and provided for both indoor and outdoor uses. 

Based on a review of the available wastewater discharges to the ocean in Southern California, it 

was determined that the primary limitation on this option is the ability to integrate it into the 

Metropolitan Water District of Southern California’s system. From discussions with 

Metropolitan Water District personnel, it was assumed that no more than 600,000 af could be 

integrated into the regional system. As noted previously, Arizona indicated a 275,000-af

potential for reuse. When traditional non-potable reuse is removed from these estimates, there is 

about 570,000 af of indirect potable reuse potential remaining. 

Although indirect non-potable reuse systems exist in some areas of the state, as much as 10 years 

would likely be needed for feasibility and permitting, with an additional 5 years for 

implementation, for a total time of 15 years.

Costs for the indirect potable options were based on a parametric cost estimating tool, resulting 

in a unit annual cost of about $1,800 per af attributable to additional treatment costs. Capital 

costs to treat and convey the water were estimated to be approximately $4.8 billion.

Other key criteria were characterized very similarly to the non-potable reuse option, with a few 

exceptions. More energy would be needed (4,300 KWh per af) due to more-stringent treatment 

requirements. Indirect or direct reuse is not widely practiced at this scale and may encounter 

public resistance. Overall water quality, given the removal of salt load (i.e., through reverse 

osmosis treatment) for these options, will improve. However, there may be localized long-term 

impacts from ocean brine disposal. 

3.0 Industrial Wastewater Reuse

Byproduct wastewater flows are generated from a variety of industries that are not discharged 

through municipal wastewater systems. Non-potable reuse of byproduct water from various 

industries was proposed to meet demands. In this case, the only representative option is general 

industrial wastewater reuse.

The consideration of industrial reuse targeted specific industries and byproducts. The target 

industries largely lie within the self-supplied or “self-served industrial” category. Targeting 

10 percent of the latter category demand results in about 40,000 af of potential reused water.
Appendix F6 — Option

Characterization – Reuse

December 2012 F6-5

Industrial reuse included treatment of produced water with total dissolved solids concentrations 

on the order of 15,000 milligrams per liter. Additional costs for collection and distribution of 

this water resulted in a unit annual cost of at least $2,000 per af.

Other key criteria were characterized very similarly to the indirect potable reuse option, with a 

few exceptions. Slightly less energy would be needed because of less-stringent treatment 

requirements. However, hauling the product water from the distributed locations may require 

diesel fuel as a significant energy source. Non-potable reuse is already a widely accepted 

process and would encounter little public resistance. Lastly, this option could increase salinity in 

the Basin because the salts are not discharged with the wastewater.

4.0 Grey Water Reuse

Grey water is generally defined as untreated wastewater that has not been contaminated by any 

toilet discharge, has not been affected by unhealthy bodily wastes, and does not present a threat 

from contamination by unhealthful processing, manufacturing, or operating wastes (California 

Building Standards Commission, 2010). The reuse or recycling of this water at individual homes 

or communities can be used for non-potable purposes. This group of options assumes reuse of 

water for non-potable purposes at individual homes and is limited by the amount of residential 

wastewater generated as well as the seasonal nature of the associated non-potable demand. The

representative option is described as: Grey Water Reuse in Adjacent Urban Areas.

4.1 Grey Water Reuse in Adjacent Urban Areas

A portion of the municipal wastewater in adjacent areas may be available for grey water reuse. It 

was assumed that approximately 50 percent of overall residential indoor water use (from 

washing machines, showers, and sinks) could be considered gray water. This 50-percent use is a 

gross assumption. Actual potential will vary significantly from place to place. It was further 

assumed that grey water could only be used for residential non-potable demands, which were 

estimated as 60 percent of the total household demand. Finally, it was assumed that an ultimate 

adoption rate of 50 percent by 2060 was achievable. These assumptions resulted in an annual 

yield of about 178,000 af by 2060.

It is important to note that in many adjacent urban areas, such as the Front Range in Colorado, 

Colorado River grey water is treated and re-diverted for reuse by municipalities or for use by 

other downstream diverters entitled to the return flows under Colorado Water Law. Use of grey 

water for irrigation may reduce treatment costs; however, unless the actual outdoor irrigation 

consumptive use is decreased, there will be no net supply increase to the system.

Grey water reuse options were also assumed to be implementable within a 10-year timeframe,

largely related to legal issues associated with plumbing code consistencies and health and safety 

concerns (individual systems). As with other options, it was assumed that these options had 

broad support.

Grey water recycling costs were derived from information at www.greywateraction.org, which 

estimated that the cost to install a sand filter to drip irrigation system was between $5,000 and 

$10,000. Assuming a cost of $5,000, with payments spread over 30 years to be consistent with 
Colorado River Basin 

Water Supply and Demand Study

F6-6 December 2012

other financial options and a single home using 0.07 af per year, grey water recycling had the 

highest cost of the reuse options based on the distributed nature of the systems at a unit annual 

cost of $4,200 per af. 

Key criteria for the grey water reuse option were characterized similarly to the other reuse 

options with a few exceptions. Grey water reuse scored well on operational flexibility because it 

would likely be implemented on a case-by-case basis, resulting in little debt service. In addition, 

grey water reuse rated high for permitting and other environmental factors in that reduced 

wastewater discharge to sewer systems would result.

5.0 Characterization Results

A summary of the characterization findings are shown in table F6-1. The top portion of the table 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the table shows the 17 criteria and associated ratings (“A” through “E”) and is 

color-scaled. In general, “C” is typically designated as mostly neutral; “A” is largely positive;

and “E” is largely negative. Refer to appendix F2 for specific criteria descriptions and rating 

scales.

6.0 References

California Building Standards Commission. 2010. California Plumbing Code.

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for the 

Water Supply of the Colorado River System.

Colorado Water Conservation Board (CWCB). Statewide Water Supply Initiative. 2010.
Appendix F6 — Option

Characterization – Reuse

December 2012 F6-7

TABLE F5-1

Summary Characterization Ratings for Reuse Options

Appendix F7

Option Characterization – Local Supply

F7-1 December 2012

Appendix F7 — Option Characterization –

Local Supply

1.0 Introduction

Local supply options have been proposed to increase the overall water supply of the Colorado 

River Basin (Basin). A number of local supply options were submitted for consideration in the 

Colorado River Basin Water Supply and Demand Study (Study). The submittals are summarized 

in appendix F2 and the original submittals are available via links from the electronic version of 

appendix F2 on the compact disc that accompanies this report and the version of appendix F2 on 

the Study website at http://www.usbr.gov/lc/region/programs/crbstudy.html.

Four options related to local supply were received. These options consisted essentially of two 

concepts:

Coal Bed Methane -Produced Water

Rainwater Harvesting

Because of the scope and level of detail provided in the proposed options, the options groups 

were also used as representative options for the characterization process. Figure F7-1 shows the 

general locations of the local supply options. In the figure, the hatched areas indicate the general 

location of the option implementation and the squares indicate where the supply would augment 

the river or where the demand would be reduced.

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Additional detail related to the 

options characterization is included in appendix F3. Attachment A of appendix F3 contains 

more detailed descriptions of the ratings. Attachment B provides the methods used for 

completing the unit cost calculations. Attachment C presents the detailed characterization 

information and is available on the compact disc that accompanies this report and on the Study 

website.
Colorado River Basin 

Water Supply and Demand Study

F7-2 December 2012

FIGURE F7-1

Generalized Locations of Local Supply Options

2.0 Coal Bed Methane-produced Water

Coal Bed Methane (CBM) is natural gas associated with coal deposits. The gas is held in place 

by the hydrostatic pressure of the water that fills factures (cleats) within a coal deposit. To 

produce gas from CBM wells, it is first necessary to reduce the hydrostatic pressure within the 

coal seam by pumping some of the water from the gas-bearing coal seams. As water is pumped 

out of the formation and the hydrostatic pressure drops, the gas desorbs from the coal into the 

cleats and migrates into the well. Generally, as the depth of the coal deposit increases, less water 

is present, and the salinity/total dissolved solids of the water is higher than for shallower

deposits.

The CBM industry has generally viewed and treated the produced water associated with gas 

recovery as a waste product that must be disposed of at the least possible cost, rather than as an 

asset that potentially could be used beneficially. In most cases, CBM-produced waters are 

currently disposed of by injection into Class II underground injection wells. This representative 

option considers treating the relatively high-salinity water and using it to augment supply in the

Basin. 
Appendix F7 — Option

Characterization – Local Supply

F7-3 December 2012

Yield estimates for CBM-produced water are based on recent CBM development data and 

production estimates combined with unit water production data specific to the Rocky Mountain 

region coal basins. Potential CBM-produced water sources within the Basin are listed in table 

F7-1.

TABLE F7-1

Location of CBM Sources

Basin/Location

CBM Produced Trillion 

Cubic Feet (TCF)

CBM Reserves (TCF)

Proved Total Estimate

San Juan (CO, NM) 9.464 8.547 10.2

Piceance (CO) 0.039

1.801 5.5

Uinta (UT, CO) 0.413

Greater Green River (WY, CO) 0.002 0.162 2.5

Source: Study of Long-Term Augmentation Options for the Water Supply of the Colorado River System. Colorado 

River Water Consultants. 2008.

In contrast to conventional gas/oil wells, where water is produced in highest quantities during the 

later portion of the well’s life as production rates decline, CBM well water production is 

normally greatest immediately after the well is brought online. When first placed online, a CBM 

well typically produces significant amounts of water (10 to 20 gallons per minute), with little or 

no gas production. Within several months of initial operation, gas production is initiated, and 

water production begins to decrease as the coal seams become dewatered. After 1 to 2 years of 

operation, water production rates per well can fall to as little as a few barrels of water per day as 

overlapping cones of depression for individual wells form in the producing area. 

For all wells (both new and extended production time wells), normalized average well lifetime 

production rates over approximately 10 years are reported to be between 2.5 and 4 gallons per 

minute (4 to 6.5 acre-feet per year [afy]). An important factor in evaluating potential CBMproduced water availability is the historical unit water production per well, which also varies 

considerably across the major coal basins. Table F7-2 summarizes available data for produced 

water on a unit basis (water obtained per 1,000 cubic feet of CBM production).

TABLE F7-2

Unit Production of CBM-Produced Water

Location

Typical Production per CBM Well

Water 

(Barrels/day)

Gas

Thousand 

Cubic Feet 

(MCF per day)

Unit Water Production Per

MCF of CBM

Barrels Gallons

Powder River Basin (MT, WY) 400 145 2.75 116

Raton Basin (NM, CO) 266 200 1.34 56

Uinta Basin (UT) 215 625 0.34 14

San Juan Basin (NM, CO) 25 833 0.03 1.3

Source: Study of Long-Term Augmentation Options for the Water Supply of the Colorado River System. Colorado 

River Water Consultants. 2008.
Colorado River Basin 

Water Supply and Demand Study

F7-4 December 2012

Using the CBM reserves data and a conservative unit water production of 5 to 10 gallons per 

MCF of CBM gas, total potential produced water volumes for the four major coal basins located 

within the Basin are projected to be between 161,000 and 322,000 acre-feet (af) based on proved 

reserves and between 279,000 and 558,000 afy based on total estimated reserves. For the 

purpose of this study, it was estimated that 4,000 and 14,000 afy of potential new supply could 

be developed considering the geographic distribution of the well sites.

Regarding time required for implementation, existing CBM wells are already producing water. 

However, the infrastructure needed to treat and convey the water from the well sites to the 

supply area is required. Additionally, to realize full-scale benefits, more CBM wells would have 

to be developed. For the Study, the time required to establish this method of treatment as a new 

supply source was assumed to be 5 years. The needed infrastructure to treat and convey the 

water was assumed to need another 5 years for construction, and the development of additional 

wells could take up to 20 years. Therefore, it would take 5 to 10 years to produce any water, and 

up to 20 years for large-scale benefits to be realized.

Because of typically poor water quality in CBM wells, required treatment facilities are the 

principal factor in capital costs. To treat 500 gallons per minute of CBM-produced water with a 

total dissolved solids concentration of 15,000 milligrams per liter, approximately $4 million in 

treatment facilities are required. Intensive pre-treatment and reverse osmosis result in estimated 

annual operating costs of $600 to $635 per af of produced water. Depending on well location, 

additional costs to convey the water could raise the total cost to as high as $5,000 per af. For the 

Study, an average unit annual cost of $2,000 per af was assumed.

Several other key characterizations were considered for the CBM-produced water option. 

National Pollutant Discharge Elimination System permits would be required to discharge the 

treated water into the watershed, and modifications to existing permits would be needed for brine 

disposal. Permits required for new wells present the most unpredictable permitting issue. Risks 

involved with implementation include the water source’s dependence on the highly volatile 

energy sector and the large spacing between wells, which increases operating costs and reduces

flexibility. Finally, the process is energy-intensive. Water desalination would require 

approximately 1,600 kilowatts hours per af, and transporting the water from individual wells to 

collection sites would most likely be accomplished using trucks.

3.0 Rainwater Harvesting

Rainwater harvesting is the capture, diversion, and storage of rainwater for landscape irrigation 

and other uses (City of Albuquerque, 1999). This representative option considers how individual 

household rainwater harvesting can increase local supply in some areas of the Basin, with 

particular emphasis on those areas that do not return flows to other users downstream. The 

analysis was limited to major urban areas of southern California, Arizona, and New Mexico that 

do not return water to the Basin.

Yield estimates for individual rainwater harvesting are based on normal precipitation in specific 

regions combined with average roof size, landscaped area, and number of households. A simple 

rainwater harvesting tool was developed that considered monthly precipitation, landscape area, 

landscape irrigation demand, roof size, and number of households to estimate the potential yield 

of rainwater harvesting systems. Average roof size was estimated to be 2,000 square feet, and 

tank size was calculated to optimize yield under varying conditions. Using a 500-gallon 
Appendix F7 — Option

Characterization – Local Supply

F7-5 December 2012

collection tank at the household level and assuming supply is only used for outside landscape 

irrigation purposes, the potential yield was calculated for representative households. The 

resulting representative household yield was then multiplied by the average number of 

households in the regions that do not have return flows to the hydrologic basin. A 50 percent

adoption rate was also assumed. The resulting basin wide yield estimate is approximately 

75,000 afy.

Rainwater harvesting is already being used in some areas of the Basin. The concept is currently 

feasible; in many cases it does not require permitting and is simple to implement, with very little 

infrastructure. Therefore, in locations where there is not a water rights issue, the 50 percent

adoption rate used to estimate yield could be achieved within 5 years. Rivers providing native 

water to the adjacent areas of Colorado are over-appropriated; therefore, any rainwater 

harvesting projects would need to be augmented. Because local supplies are not available, 

augmentation would increase the use of Colorado River water. Similarly, Utah in particular, 

broad-scale rainwater harvesting would likely elicit water rights concerns to downstream water 

users and state law is currently restrictive. In Colorado and Arizona, rainwater harvesting is not 

legal due to the prior appropriation system upon which Colorado and Arizona’s water systems 

are based. Therefore, rainwater harvesting was not considered as a local supply option in 

Colorado, Arizona, or Utah.

The cost for purchase and installation of a 500 gallon storage tank and irrigation modifications 

was assumed to be $1,000 per household. Because of the limited storage capacity and the 

mismatched timing of rain events and demand, harvested rainwater only delivers approximately 

10 percent of outdoor demand, or approximately 0.02 per afy per household. As a result, the 

calculated unit annual cost of water was estimated as $3,150 per af. 

Aside from the high capital cost for individual households, the rainwater harvesting options are 

easy to implement, are already practiced in many states, have no energy needs, and, depending 

on state and local laws, do not require any permitting. 

4.0 Characterization Results

A summary of the characterization findings are shown in table F7-3. The top portion of the table 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the table shows the 17 criteria and associated ratings (“A” through “E”) and is 

color-scaled. In general, “C” is typically designated as mostly neutral (yellow); “A” is largely 

positive (green); and “E” is largely negative (red). Refer to appendix F3 for specific criteria 

descriptions and rating scales.

5.0 References

City of Albuquerque. 1999. Rainwater Harvesting Supply from the Sky.

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for the 

Water Supply of the Colorado.
Colorado River Basin 

Water Supply and Demand Study 

F7-6 December 2012 

TABLE F7-3 

Summary Characterization Ratings for Local Supply Options
Appendix F8 

Option Characterization – 

Watershed Management

December 2012 F8-1 

Appendix F8 — Option Characterization – 

Watershed Management

1.0 Introduction

Watershed management options have been proposed to increase the overall water supply of the 

Colorado River Basin (Basin). A number of watershed management options were submitted for 

consideration in the Colorado River Basin Water Supply and Demand Study (Study). Because of 

the scope and level of detail provided in the proposed options, the option groups are also used as 

representative options. When potential yield of a representative option exceeds 200 kafy and the 

option is scalable, the representative option was characterized in progressive 200 kafy “steps”. 

The submittals are summarized in appendix F2 and the original submittals are available via links 

from the electronic version of appendix F2 on the compact disc that accompanies this report and 

the version of appendix F2 on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

Ten options related to watershed management were received. The following submitted options 

were reviewed and organized into five groups according to the specific type of watershed 

management approach:

• Tamarisk Control 

• Forest Management

• Brush Control 

• Dust Control 

• Weather Modification

Figure F8-1 shows the general locations of the watershed management options and their 

approximate extent.

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Additional detail related to the 

options characterization is included in appendix F3. Attachment A of appendix F3 contains 

more detailed descriptions of the ratings. Attachment B provides the methods used for 

completing the unit cost calculations. Attachment C presents the detailed characterization 

information and is available on the compact disc that accompanies this report and on the Study 

website.

2.0 Tamarisk Control

Control of invasive tamarisk trees has been proposed for riparian areas to reduce their overall 

consumptive use and increase streamflow. The estimates for tamarisk control were based 

primarily on the Colorado River Basin Tamarisk and Russian Olive Assessment prepared for the 

Basin States1 by the Tamarisk Coalition in 2009. 

Yield estimates for all watershed management concepts were developed by evaluating the 

fundamental aspects of watershed hydrology related to the amount of runoff that is generated and 

 

1 Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming.
Colorado River Basin

Water Supply and Demand Study

F8-2 December 2012

then assessing the impacts of changes to basic runoff parameters. In this case, the parameter 

proposed to be modified to increase runoff is reduction in evapotranspiration from tamarisk trees 

or a forest. 

FIGURE F8-1 

Generalized Locations of Watershed Management Options

Yield for tamarisk control was based on the area over which the measure was implemented and 

the change in evapotranspiration resulting from the vegetation management measure. The 

estimated change in evapotranspiration was then related to the overall water balance to estimate 

the change in runoff associated with the measure. 

The total tamarisk acreage in the Basin has been mapped as 250,000 acres (Tamarisk Coalition, 

2009). This value must be considered low because a significant amount of the data is point data 

with no actual acreage assigned to this information. If one-fourth of the total tamarisk acreage 

can be removed by a tamarisk management program, the total acres for the program are 60,000. 

Estimates of water savings by removal of tamarisk and replacement by other species range from 

zero and up to 1.5 acre-feet (af) per acre (Nagler et al., 2009). A reasonable estimate for 

planning purposes is 0.54 af per acre (Tamarisk Coalition, 2009). At that rate of water savings, 

conversion of 60,000 acres from tamarisk to other species would save 30,000 acre-feet per year 

(afy) of consumptive water use. 
Appendix F8 — Option Characterization – 

Watershed Management

December 2012 F8-3 

Although all of the vegetation management options are based on control of vegetative conditions 

to improve watershed runoff capabilities, there are significant differences in terms of areal extent 

and degree of current adoption that affect the evaluation of timing for implementation. Tamarisk 

control is focused on removal of tamarisk in riparian areas and their replacement with species 

that do not consume as much water. It was estimated that 2 years would be required to evaluate 

the feasibility of this practice. This short duration reflects the widespread current adoption of 

these practices across the Basin, although at a much smaller scale than envisioned by this option. 

Permitting at the scale considered here would require approximately 5 years. Implementation 

time is estimated to be 5 years based on the large area proposed for tamarisk control. Therefore, 

the total time estimated for reduction in consumptive use through control of tamarisk is estimated 

to be 12 years.

Cost estimates for tamarisk management options were derived primarily through literature 

research and actual project implementation experiences (Barz et al., 2009; Tamarisk Coalition, 

2009) and applying the costs to these concepts. Cost estimates for tamarisk management 

measures are highly variable, due primarily to the variability in site conditions such as tamarisk 

density, which control the method to use, site access, etc. The uncertainty relates not only to the 

costs of the practices used to accomplish tamarisk management but also to the effectiveness of 

these measures and the frequency with which the measures might have to be repeated. For 

example, some sites are better managed by more–frequent, smaller-scale removal than by lessfrequent, large-scale mobilization and activity.

The Tamarisk Coalition has estimated that the unit annual costs of water saved by tamarisk 

management range from $260 to $1,050 per af (Tamarisk Coalition, 2009), with a Basin-wide 

average unit annual cost of less than $400 per af. For the purposes of the Study, a unit annual 

cost of $400 per af was assumed. 

In addition to yield, timing, and cost, the tamarisk management options were characterized 

against several other criteria. A summary of the findings for all criteria is shown in table F8-1. 

Key considerations related to technical feasibility, permitting, legal, and policy were largely 

covered in the descriptions related to option timing. Tamarisk management ranked low on longterm viability due to the uncertainty as to whether the quantity of yield could be achieved or 

maintained over time. For operational flexibility, tamarisk management ranked low because the 

option cannot be idled from year to year without substantial loss of subsequent yield. When 

considering hydropower, water quality, recreation, and other environmental criteria, options that 

resulted in more water in headwaters locations were rated high. Socioeconomic impacts were 

generally judged to be neutral because all options created some jobs, although the number of jobs 

might vary from year to year.

3.0 Forest Management

Forest management entails the replacement of mature forests that have been cleared by 

harvesting, fires, or insect infestations with stands of replacement growth more likely to be 

favorable for generating runoff. This option suggests that initial yield realization may be 

300,000 afy in forested areas of Colorado based on active management of 5 percent of 

Colorado’s forests and assuming 4 inches of increased yield (National Research Council, 2008). 

However, the increased yield is expected to rapidly decline as new growth begins to replace 

harvested areas. The increased yield is anticipated to only last about 3 to 4 years and provide no 

benefit thereafter. The concept may only be feasible if the approach is via selective harvest of 
Colorado River Basin

Water Supply and Demand Study

F8-4 December 2012

mature trees in areas where density is too high, combined with understory clearance. 

Characterization of this option was performed as increments of 200 thousand acre-feet per year 

(kafy) in order to capture issues of scale and other complexities of large-scale programs.

Forest management of areas over which selective harvesting is practiced or over which extensive 

forest fires have occurred provide the opportunity for programmed revegetation. The time to 

evaluate the feasibility of these activities was estimated as 7 years. The timeframe for permitting 

was estimated to be 3 years, largely due to the consideration that these forest management 

activities are currently being practiced (MacDonald and Stednick, 2003), although not for 

purposes of increasing runoff. The timing for implementation of forest management practices 

was estimated at 10 years to conform to timeframes of other forest management measures. 

Therefore, the total time for development of forest management options is estimated to be 

20 years. 

Cost estimates for forest management options were derived primarily through literature research 

and applying the costs presented in the literature to these concepts. Cost estimates for forest 

management measures are generally highly uncertain. The uncertainty relates not only to the 

costs of the practices used to accomplish forest management but also to the effectiveness of these 

measures and the frequency with which the measures might have to be repeated. 

The extent to which existing forest roads are available will have a significant impact on cost. 

Estimates of unit annual costs experienced by the US Forest Service for similar management 

activities ranged from $114 to $786 per acre, with estimates for individual forest areas between 

$215 to $1,500 per acre on a 20-year rotation (National Research Council, 2008, and Evans, 

2008). The median unit annual cost value was $875 per acre. Assuming a unit annual cost of 

$1,000 per acre on a 20-year rotation and annual maintenance costs of about 10 percent of that 

amount, the unit annual cost of additional runoff generated is approximately $500 per af. This 

estimate is based on annualized costs of $160 per acre treated with each acre treated generating

one-third of an af of additional runoff. The resulting characterizations of other key criteria for 

this option were very similar to the tamarisk control option. 

4.0 Brush Control 

Brush control involves reducing brush and therefore reducing consumptive use by brush 

vegetation. 

Brush control may have limited benefit in arid regions. It has been demonstrated that improved 

runoff conditions are unlikely for regions receiving less than 18 inches of rainfall annually (Ball 

and Taylor, 2008). Most of the areas where brush control has been considered within the Basin 

are in the regions with less than 18 inches of annual precipitation. For evaluation purposes, it 

was roughly assumed that in these arid areas average runoff is between 0.05 and 0.1 inch per 

year (Linsley et al., 1982). The area covered by U.S. Bureau of Land Management (BLM) land 

in the Basin is approximately 100,000 square miles, resulting in a range of 250,000 to 500,000 

afy in total runoff. Assuming brush control resulted in a 10 percent increase in runoff, between 

25,000 and 50,000 afy of net benefit would realized. 

Brush control on BLM land involves the conversion of vegetative cover from trees such as 

mesquite and juniper to native grasses. This has been implemented over small areas, but not 

over the large area envisioned by this option. The implementation would also require 

programmatic and financial support from federal and state agencies as well as coordination with 
Appendix F8 — Option Characterization – 

Watershed Management

December 2012 F8-5 

private contractors who are using the BLM land for grazing. It was estimated that the time 

requirements for evaluation of feasibility would be 5 years, for permitting would be 5 years, and 

for phased implementation would be 5 years, for a total of at least 15 years for availability of 

increased runoff from brush control on BLM land. 

The preferred method of control would be spraying the brush with herbicides formulated for 

control of the selected variety of brush, followed by mechanical removal of the brush, and then 

seeding with native grasses to revegetate the affected areas. Chemical spraying costs about $30 

per acre and has to be repeated at about 10-year intervals (Research & Planning Consultants, 

2000). If yields could be achieved and maintained, the unit annual cost would approximately be 

$7,500 afy per year. 

Other key criteria were characterized similarly to the other two vegetation management options. 

5.0 Dust Control

These options propose to control land-based dust sources that contribute to dust accumulation on 

snow, which changes the albedo, or reflective power, of the snow and results in earlier snowmelt 

(Painter et al., 2007, 2010 and 2012; Skiles et al., 2012) and more evaporative moisture losses. 

By implementing measures to reduce the accumulation of dust on snow, lower evaporative losses 

are anticipated. This is a relatively new concept supported by recent literature (Painter et al., 

2007).

Referenced modeling studies by the National Oceanic and Atmospheric Administration (Painter 

et al., 2010) and others indicate that as much as 800,000 afy might be recovered by controlling 

the amount of dust accumulating on snow. However, these studies do not address the practicality 

of implementing measures to control dust generation in the large area of the Colorado Plateau. 

Management practices to reduce dust emissions may include soil fences, straw grids, and/or 

revegetation. Another promising although largely untested technique involves the spray 

application of cyanobacteria to promote the formation of biological soil crusts that reduce 

erosion. 

Due to the uncertainty about the effectiveness of measures to control the generation of dust and 

prevent its deposition on snow, the amount of additional runoff that could be obtained was 

estimated to be no more that 50 percent of the total potential amount, or 400,000 afy. 

Characterization of this option was performed as two increments reflecting a more focused 

program of “hot spot” regions for the first 280 kafy, and a more distributed program for the 

remaining 120 kafy. Characterization of this option was performed as increments of 

200 thousand acre-feet per year (kafy) in order to capture issues of scale and other complexities 

of large-scale programs.

The primary factor in determining the timing of increased runoff through dust control measures 

is the relatively large portion of the Colorado Plateau and the Great Basin over which dust 

control practices would need to be implemented. The large areal extent led to estimates of 5 

years to evaluate effectiveness, followed by 5 years for permitting, and 5 years for the first phase 

of implementation, for a total of 15 years. The essential element of implementation is the 

widespread adoption of practices to minimize wind erosion over large areas. This is most likely 

to be accomplished through financial, regulatory, and educational measures promoted at both 

federal and state levels.
Colorado River Basin

Water Supply and Demand Study

F8-6 December 2012

To approximate the cost of programs for dust management, it was assumed that conversion of the 

erodible lands to native grasses would require practices similar to enrollment in the 

U.S. Department of Agriculture’s Conservation Reserve Program (2008). These costs were 

estimated for clearing the land by root plowing and then reseeding with native grass. It was also 

assumed that periodic maintenance by spraying would be required at approximately 10-year 

intervals. Based on the costs of these practices, an annual average cost of $15 per acre was 

derived. Implemented over an area of 10,000 square miles, the annualized cost per af of 

increased yield is $500. Although the eventual dust control program may implement a variety of 

control measures, these technologies are not yet established for the Basin.

Other key criteria were characterized similarly to other watershed management practices.

6.0 Weather Modification

This watershed management concept features two mechanisms that have been proposed for 

increasing precipitation over the Basin. The first is by cloud seeding, particularly to increase 

snowfall in mountain regions. The second is by creating more inland seas to increase the amount 

of atmospheric moisture due to increased evaporation. 

Many earlier studies were summarized in a report prepared by the Metropolitan Water District of 

Southern California (Ryan, 2005). This report indicates that cloud seeding in runoff- producing 

areas could generate as much as 1.1 to 1.8 million additional afy in the Upper Basin and as much 

as 830,000 afy in the Lower Basin and adjacent basins. The report concluded that the potential 

maximum amount that could be generated from cloud seeding to provide additional runoff would 

be about 1,700,000 afy. Characterization of this option was performed as increments of 200 kafy

in order to capture issues of scale and other complexities of large-scale programs.

There has been a long history of weather modification activities throughout the Basin. Based on 

these existing practices, no additional time would be required for feasibility or permitting. 

Implementation could be completed in 5-year phases.

For weather modification by cloud seeding, separate cost estimates were derived from the 

California Department of Water Resources and from the documentation provided in the Study of 

Long-Term Augmentation Options for the Water Supply of the Colorado River System (Colorado 

River Water Consultants, 2008). The California Department of Water Resources (2005) 

indicated that cloud seeding produced 300,000 to 400,000 af of additional runoff at a cost of 

around $7 million. The investigations associated with the augmentation study led to a unit 

annual cost estimate of $20 to $30 per af. 

The other weather modification option proposed was to increase atmospheric moisture and 

thereby precipitation by creating more inland seas. Research (Trenberth, 1999) has indicated 

that less than 3 percent of precipitation is derived from local evaporation in the Southwest, 

though estimates based on moisture budget suggest higher precipitation-recycling ratio 

(Anderson, 2009). Not all local evaporation contributes to moisture that is recycled as 

precipitation in the hydrologic basin. Therefore, while increasing evaporation may marginally 

increase precipitation, it is likely that the water balance change is negative. A yield value of zero

was assigned. 

In addition to yield, timing, and cost, the watershed management options were characterized 

against several other criteria. Key considerations related to technical feasibility, permitting, 
Appendix F8 — Option Characterization – 

Watershed Management

December 2012 F8-7 

legal, and policy were largely covered in the descriptions related to option timing. Many of the 

options ranked low on long-term viability due to the uncertainty related to whether the quantity 

of yield could be achieved or maintained over time. For operational flexibility, weather 

modification ranked high for this criterion because it can be easily implemented on various 

scales from year to year. When considering hydropower, water quality, recreation, and other 

environmental criteria, options that resulted in more water in headwaters locations were ranked 

positively. Socioeconomic impacts were generally judged to be neutral because all options 

created some jobs, although the number of jobs might vary from year to year. 

7.0 Results 

A summary of the characterization findings are shown in table F8-1. The top portion of the table 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the table shows the 17 criteria and associated ratings (“A” through “E”) and is 

color-scaled. In general, “C” is typically designated as mostly neutral (yellow); “A” is largely 

positive (green); and “E” is largely negative (red). 

Refer to appendix F3 for specific criteria descriptions and rating scales. Options that yield more 

than 200 kafy were broken into 200 kafy steps and numbered sequentially (e.g., WatershedForest Step 1, Watershed-Forest Step 2, etc.). 
Colorado River Basin

Water Supply and Demand Study

F8-8 December 2012

TABLE F8-1 

Summary Characterization Ratings for Watershed Management Options
Appendix F8 — Option Characterization – 

Watershed Management

December 2012 F8-9 

8.0 References 

Anderson, Bruce T. 2009. “Estimating the Influence of Evaporation and Moisture-Flux 

Convergence upon Seasonal Precipitation Rates. Part II: An Analysis for North 

America Based upon the NCEP–DOE Reanalysis II Model.” Journal of 

Hydrometeorology, vol 10. August. 

Ball, Laura, and Melinda Taylor (Environmental Defense). 2008. Brush Management: Myths 

and Facts. 

Barz, Dave, Richard P. Watson, Joseph F. Kanney, Jesse D. Roberts, and David P. 

Groeneveld. 2009. Cost/Benefit Considerations for Recent Saltcedar Control, 

Middle Pecos River, New Mexico, Environmental Management, 43:282-298. 

California Department of Water Resources. 2005. California Water Plan Update, Public 

Review Draft. 

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for 

Water Supply of the Colorado River System. 

Evans, Alexander M. 2008. “Synthesis of Knowledge from Woody Biomass Removal Case 

Studies.” Forest Guild, U.S. Forest Service. 

Linsley, Ray K, Max A. Kohler, and Joseph L.H. Paulhus. 1982. “Hydrology for 

Engineers.” McGraw-Hill Series in Water Resources and Environmental 

Engineering. 

MacDonald, Lee H., and John D. Stednick. 2003. “Forests and Water: A State-of-the-Art 

Review for Colorado.” Colorado State University, CWRRI Completion Report No. 

196. 

Nagler, Pamela, Kiyomi Morino, Kamel Didan, Joseph Erker, John Osterberg, Kevin 

Hultine, and Edward Glenn. 2009. Wide-Area Estimates of Saltcedar 

Evapotranspiration on the Lower Colorado River Measured by Heat Balance and 

Remote Sensing Methods. 

National Research Council. Committee on Hydrologic Impacts of Forest Management of the 

Water Science and Technology Board of the 2008. Hydrologic Effects of a Changing 

Forest Landscape. 

Painter, T. H., A. P. Barrett, C. C. Landry, J. C. Neff, M. P. Cassidy, C. R. Lawrence, K. E. 

McBride, and G. L. Farmer. 2007. “Impact of disturbed desert soils on duration of 

mountain snow cover.” Geophys. Res. Lett., 34, L12502, 

doi:10.1029/2007GL030284. 

Painter T, Deems J, Belnap J, Hamlet A, Landry C, and Udall B. 2010. “Response of 

Colorado River runoff to dust radiative forcing in snow.” Proceedings of the 

National Academy of Sciences. 

Painter, T. H., S. M. Skiles, J. S. Deems, A. C. Bryant, and C. C. Landry. 2012. “Dust 

Radiative Forcing in Snow of the Upper Colorado River Basin: 1. A 6 Year Record of 
Colorado River Basin

Water Supply and Demand Study

F8-10 December 2012

Energy Balance, Radiation, and Dust Concentrations.” Water Rour. Res., 48, 

W07521, doi:10.1029/2012WR011985. 

Research & Planning Consultants. 2000. Assessment of Brush Control as a Water 

Management Strategy. 

Ryan, Tom (Metropolitan Water District of Southern California) 2005. Weather 

Modification for Precipitation Augmentation and Its Potential Usefulness to the 

Colorado River Basin States. 

Skiles, S. M., T. H. Painter, J. S. Deems, A. C. Bryant, and C. C. Landry. 2012. “Dust 

radiative forcing in snow of the Upper Colorado River Basin: 2. Interannual 

variability in radiative forcing and snowmelt rates.” Water Resour. Res., 48, W07522, 

doi:10.1029/2012WR011986. 

Tamarisk Coalition. 2009. Colorado River Basin Tamarisk and Russian Olive Assessment.

Trenberth, K. E. 1999. Atmospheric moisture recycling: Role of advection and local 

evaporation. J. Climate, 12, 1368–1381. 

U.S. Department of Agriculture, Farm Service Agency. 2008. Program Fact Sheet on 

Conservation Reserve Program (CRP) Benefits: Water Quality, Soil Productivity and 

Wildlife Estimates.
Appendix F9

Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-1

Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

1.0 Introduction

Development of additional municipal and industrial (M&I) water conservation was proposed to 

further reduce the overall M&I water demand in areas currently relying on water supply from the 

Colorado River system. A number of M&I conservation options were submitted for 

consideration in the Colorado River Basin Water Supply and Demand Study (Study). The 

submittals are summarized in appendix F2 and the original submittals are available via links 

from the electronic version of appendix F2 on the compact disc that accompanies this report and 

the version of appendix F2 on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html.

Several of the submitted options suggested specific conservation measures, many of which have 

been implemented at locations in the Study Area. The total potential yield of M&I conservation 

exceeds 200 kafy, therefore the representative option was characterized in progressive 200 kafy 

“steps” to represent potential project phasing. Figure F9-1 shows the primary M&I demand 

locations.

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Additional detail related to the 

options characterization is included in appendix F3. Attachment A of appendix F3 contains more 

detailed descriptions of the ratings. Attachment B provides the methods used for completing the 

unit cost calculations. Attachment C presents the detailed characterization information and is 

available on the compact disc that accompanies this report and on the Study website.

2.0 Overall Approach

27 options were submitted that related to additional M&I conservation to reduce demand in areas 

receiving Colorado River supply. Many of these options were related to specific M&I 

conservation programs (e.g., water auditing, xeriscaping, inclining block rates, etc.) or targeted 

specific M&I water use sectors (e.g., golf courses, industrial use) that might provide additional 

opportunities for M&I conservation in the Colorado River Basin (Basin) as a whole. 

Three representative options were developed from the submitted options, reflecting different 

degrees of additional M&I conservation. The representative options consist of three “levels” of 

conservation, with progressively ambitious goals (Level 1, Level 2, and Level 3) that would be 

implemented sequentially. The representative options reflect conservation in addition to that 

already included in the demand scenarios in the Study. 
Colorado River Basin

Water Supply and Demand Study

F9-2 December 2012

FIGURE F9-1

Primary M&I Demand Locations

3.0 Overall Approach

Approximately 50 options were submitted that related to additional M&I conservation to reduce 

demand in areas receiving Colorado River supply. Many of these options were related to 

specific M&I conservation programs (e.g., water auditing, xeriscaping, inclining block rates, 

etc.) or targeted specific M&I water use sectors (e.g., golf courses, industrial use) that might 

provide additional opportunities for M&I conservation in the Basin as a whole. 

Three representative options were developed from the submitted options, reflecting different 

degrees of additional M&I conservation. The representative options consist of three “levels” of 

conservation, with progressively ambitious goals (Level 1, Level 2, and Level 3) that would be 

implemented sequentially. The representative options reflect conservation in addition to that 

already included in the demand scenarios in the Study. 

These levels of additional M&I demand reduction would likely be implemented through use of 

progressively ambitious water conservation best management practices (BMP) and adoption 

rates targeting residential indoor; commercial, institutional, and industrial (CII); outdoor 

landscaping; and water loss demand.
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-3

Because levels of current and projected future conservation vary throughout the Study Area, 

different levels of potential savings are possible for a given conservation measure. These 

savings range from essentially no savings where measures have been fully implemented to 

significant savings where measures have not been implemented or where adoption rates are 

relatively low. Disaggregating the savings potential by conservation measure and individual 

location was beyond the scope of the Study. Instead, M&I conservation measures were 

considered for the entire Study Area with the acknowledgement that, despite state and regional 

differences in current levels of conservation and potential for future conservation, additional 

conservation is achievable on a Study Area-wide basis. Likewise, it was assumed that additional 

conservation is due to an “active” incentive-based program, such as paying for conversion of turf

to xeriscape, toilet replacement, etc. 

Table F9-1 presents a list of the types of urban water conservation BMPs included in several 

guidance and water planning documents produced for the Study Area. These include BMPs in 

guidance documents from California, Colorado, and the U.S. Environmental Protection Agency 

(EPA). In addition, table F9-2 presents a list of BMPs considered in the conservation planning 

aspects of the Metropolitan Water District (MWD) of Southern California’s Integrated Resources 

Plan (2010). These lists include BMPs that are considered in many M&I water conservation 

plans and are consistent with the BMPs included in statewide and regional documents and 

studies by the California Urban Water Conservation Council (CUWCC) (2005), Colorado Water 

Conservation Board (CWCB) (2010), and CALFED (2006). 

Many of these BMPs have already been enacted throughout the Study Area, resulting in 

significant conservation savings. For example, a recent study of municipal deliveries of 

Colorado River water (Pacific Institute, 2010) found that most of the municipalities receiving 

Colorado River water had produced significant reductions in per capita water deliveries for the 

period 1990 to 2008. A number of states, including California and Utah, have programs in place 

that require a certain amount of reduction over time, such as California’s 20x2020 program 

(California Department of Water Resources, 2010). Arizona has a statewide conservation plan 

and specific conservation requirements associated with individual Active Management Areas 

(Arizona Department of Water Resources, 2008). Likewise, a number of individual 

communities, including Albuquerque, Denver, Las Vegas, Phoenix, and Tucson, have specific 

M&I conservation goals. The associated conservation programs employ many of the BMPs 

shown in tables F9-1 and F9-2. 
Colorado River Basin

Water Supply and Demand Study

F9-4 December 2012

TABLE F9-1

Example Urban BMPs for Water Conservation

California Urban Water 

Conservation Council (2005, 2011)

Colorado Statewide Water 

Supply Initiative (CWCB, 2010)

EPA Water Conservation Plan 

Guidelines (EPA,1998)

Residential Survey Programs Metering Universal Metering

Residential Plumbing Retrofit Plumbing Codes and Fixture 

Standards

Water Accounting and Loss 

Control

System Water Audits Public Education Costing and Pricing

Metering w/Commodity Rates Leak Detection Information and Education

Large Landscape Conservation Water Audits (indoor, 

commercial, and landscape)

Water Use Audits

High Efficiency Clothes Washers Irrigation Efficiency Evaluations Retrofits

Public Information Programs High-efficiency Fixture and 

Appliance Replacement

Pressure Management

School Education Programs Rebates for Toilets and Washers Landscape Efficiency

Commercial Industrial Institutional Turf Replacement and 

Restrictions

Replacements and Promotions

Wholesaler Agency Assistance 

Programs

Pricing and Surcharges Water Use Regulation

Conservation Pricing Fixture Retrofit on Sale of 

Property

Reuse and Recycling

Conservation Coordinator Eliminate High-Water Use 

Landscape

Integrated Resource 

Management

Water Waste Prohibitions Elimination of Single-Pass 

Cooling

Residential Ultra-Low Flush Toilet 

Replacement Programs

Non-water Using Urinals in NonResidential 

Note that an amended Memorandum of Understanding was signed on 9/14/2011 that revised the list shown 

for the CUWCC. The revision included a re-categorization of the above broad BMPs, as found at 

http://www.cuwcc.org/mou/exhibit-1-bmp-definitions-schedules-requirements.aspx.
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-5

TABLE F9-2

Example BMPs Considered in MWD’s Integrated Resource Planning (MWD, 2010)
Colorado River Basin

Water Supply and Demand Study

F9-6 December 2012

In order to examine the potential for additional M&I conservation and to explore the range of 

costs and other factors, three levels of conservation were considered based on assumed levels of 

reductions and adoption (or penetration) rates for residential indoor, CII, landscape, and water 

loss. Table F9-3 presents the assumptions for Level 1, Level 2, and Level 3 conservation. The 

levels of reduction in table F9-3 are based on estimates of the use rates by demand type in 2015

(e.g., ~69 gallons per capita per day [gpcd] Study Area indoor water use). The assumptions in 

table F9-3 were derived from state of Colorado (Colorado Water Conservation Board, 2011) and 

California (CALFED, 2006) approaches and applied to Study Area projected demand to result in 

a Basin-wide estimate of potential water savings. The assumptions were derived for purposes of 

the Study and do not necessarily reflect realistic or achievable local conservation goals. 

TABLE F9-3

Municipal and Industrial Water Conservation Assumptions

Level 1 Level 2 Level 3

Residential Indoor

Indoor gpcd 60 50 40

Adoption rates 50% 60% 70%

Example types of BMPs: Public education programs, conservation-oriented plumbing and building codes, 

residential water surveys, high-efficiency showerheads and faucets, ultra low-flow toilets, efficient clothes washers, 

meter retrofits.

Commercial, Institutional, and Industrial 

Target reduction in demand 15% 25% 30%

Adoption rates 50% 60% 70%

Example types of BMPs: Public education programs, conservation-oriented plumbing and building codes, green 

building codes, CII surveys and audits, high-efficiency faucets and fixtures, ultra low-flow toilets, high efficiency 

clothes waters, dishwasher high-efficiency pre-rinse spray valves, meter retrofits, efficiency in industrial processes 

and cooling .

Outdoor Landscaping

Target reduction in demand 15% 25% 35%

Adoption rates 50% 60% 70%

Example types of BMPs: Public education programs, conservation-oriented pricing, large landscape water surveys 

and audits, evapotranspiration-based irrigation controllers, large landscape separate metering, irrigation efficiency 

improvements, conversion of turf to lower water use landscaping.

Water Loss

Target water loss 7% 7% 7%

Adoption rates 50% 60% 70%

Example types of BMPs: Utility water loss control, supply system audits and leak detection programs.

Conservation levels from estimated use rates by demand type in 2015.

4.0 Potential M&I Conservation Measures

4.1 Residential Indoor Conservation Measures

The minimum indoor residential water use was assumed to be about 45 gpcd for “existing 

homes”, based on research from the American Water Works Association (1999) and recent 

analysis of residential water use performed for EPA (Aquacraft, 2011). “New homes” were 
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-7

assumed to potentially achieve a minimum 35.6 gpcd based on EPA research of “high 

efficiency” new homes under the WaterSense program specifications. These data were assumed 

to bracket a minimum “potential” for residential indoor gpcd. Residential indoor yield was 

calculated for a given level of conservation based on a per capita use target and an assumed 

adoption rate. 

4.2 CII Conservation Measures

CII water use is highly variable in the Study Area and is heavily dependent on the mixture and 

type of industry in the community. Without further characterization and study, a “minimum” CII 

rate estimate would be highly speculative. Instead, it was assumed that a CII demand could be 

reduced by a percentage of total CII demand through the implementation of standard BMPs, as 

outlined in programs by CUWCC (2005, 2011), CWCB (2010), and others. CII demand 

reduction was calculated for a given level of conservation based on a reduction target and an 

assumed adoption rate. Reductions in CII demand were consistent with the range of CII 

reductions contemplated in Colorado’s SWSI 2010 Municipal and Industrial Water Conservation 

Strategies (CWCB, 2011).

4.3 Outdoor Landscaping Conservation Measures

Outdoor water use within an M&I service area is primarily for lawn irrigation and landscaping at 

single-family homes, neighborhood/community parks, golf courses, commercial building 

landscaping, and median landscaping. The estimated minimum outdoor water use in a 

community is based on assumptions related to levels of landscape area and percent of turf that 

may exist in the future, while maximizing the water efficiency of the required irrigation. 

It was assumed that outdoor use could be reduced by a percentage of total outdoor use through 

the implementation of standard BMPs as outlined in programs by CUWCC, CWCB, and others. 

Outdoor use reduction was calculated for a given level of conservation based on a reduction 

target and an assumed adoption rate. Reductions in outdoor demand were consistent with the 

range of outdoor reductions contemplated in Colorado’s SWSI 2010 Municipal and Industrial 

Water Conservation Strategies (CWCB, 2011). However, as documented in the Metropolitan 

Round Table Conservation Paper, Colorado Front Range municipalities agree that, although 15 

percent is reasonable, higher levels may be hard to achieve.

4.4 Water Loss Reductions

Water loss occurs in water utilities’ distribution systems and represents an opportunity for water 

conservation. Distribution system auditing, leak detection and repair, replacement of aging 

infrastructure, and recurring maintenance activities can reduce the loss between diversion and the

meter at the house or business. These water loss reduction measures are applied at the 

municipality or utility level and reflect an increase in the accounting and control over water 

distribution. Water loss reduction was calculated based on a target water loss percentage of 7

percent and an assumed adoption rate that varies by level of conservation. 

5.0 Regional Considerations

The potential M&I water conservation measures are assumed to apply to the overall Study Area, 

but significant differences in potential water savings exist between geographies based on the 
Colorado River Basin

Water Supply and Demand Study

F9-8 December 2012

current level of conservation adoption, commercial and industrial base, and climate. In addition, 

because return flows augment river flow for in-Basin locations, indoor conservation has little to 

no net effect on water demand. For in-Basin locations, only reductions in consumptive use will 

reduce overall Colorado River system demand as the return flows from the urban areas is 

returned to the Colorado River. In addition, the amount of reduction in Colorado River demand 

varies by location. 

In many of the major urban areas receiving Colorado River water, the overall water supply 

provided to communities consists of a significant portion of other supplies (other surface 

supplies, groundwater supplies, reuse, etc.) in addition to Colorado River water. In most of these 

out-of-Basin areas, the supplies are comingled in the water supply and distribution systems 

before delivery to the consumer. Because the conservation measures are end-use water demand 

reductions, the water savings result in a net demand reduction. In these areas, the net M&I 

demand reductions may not result in the same amount of demand reduction for Colorado River 

water. This is the result of the distributed nature of conservation efforts and the inability of 

conservation to target one type of supply in regions that have diverse water supply portfolios. 

For example, MWD’s service area receives approximately 40 percent of its total water supply 

portfolio from the Colorado River, as noted in Technical Report C – Water Demand Assessment, 

whereas northern California supplies via the State Water Project, Los Angeles Aqueduct 

supplies, local surface and groundwater supplies, and reuse contribute the remaining supply. 

Water conservation will reduce the overall demand on these supplies collectively, but is not 

likely to result in a one-for-one reduction in Colorado River demand. However, an overall 

reduction in demand could potentially reduce demands on each supply source, resulting in an 

overall benefit. Alternatively, reductions in consumptive use in Nevada result in an equal 

potential reduction in Colorado River demand. 

In many adjacent areas, including the Front Range of Colorado, water exported from the Basin is 

reused essentially to extinction. Municipal conservation in these areas reduces the amount of 

water available for reuse, and does not result in a one-for-one reduction in Colorado River 

demand.

In many areas, the marginal cost of water from the Colorado River is lower than for other new 

supplies, and it is likely that M&I water conservation may result in the deferral of the 

development of new supplies rather than direct reductions in Colorado River system demand. 

However, for the purposes of the Study it was assumed that water conservation savings would be 

allocated to the supply sources in proportion to their contribution to the overall water supply 

portfolio. For the entire Study Area, the average Colorado River system M&I demand is about 

40 percent of the total Study Area M&I demand. However, because these demand reductions 

benefit more than just Colorado River water users, the costs of achieving these reductions was

assumed to be shared by the beneficiaries.

6.0 Implementation Approaches

The primary implementation approach under consideration for M&I water conservation is an

incentive-based program. M&I water conservation programs are typically implemented through 

adoption and verification of a broad suite of BMPs such as those described previously. Public 

education programs, regulations dictating standard practices for new development, and incentivebased programs encouraging more efficient water use are typically implemented. These 
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-9

programs provide the necessary incentives (financial or otherwise) to achieve the levels of 

conservation. Financial incentives provide a cost share for implementation of BMPs and have 

been widely used to facilitate conversion to higher-efficiency fixtures and toilets. These types of 

mechanisms are anticipated to continue to be widely used to achieve higher levels of 

conservation in areas served by Colorado River system water. Non-incentive based approaches 

are considered as well, consistent with the BMP examples shown in table F9-3. Both approaches 

are effective and contribute to market transformation, which provides reliable long-term water 

savings.

7.0 Quantity of Yield

As described in Technical Report C – Water Demand Assessment, M&I water conservation 

measures have been implemented at locations throughout the Basin, resulting in significant 

reductions from historical per capita use. Demand scenarios developed for the Study include, to 

varying degrees, by both scenario and location, some portion of passive conservation (resulting 

from outside entities/programs, such as federal standards) and active conservation (resulting 

from active state and local programs). In general, consideration of active programs was limited 

to those already in place or logically following the storyline for a given demand scenario (e.g.,

social values of the Enhanced Environment scenario).

Considerable conservation is included in these demand scenarios. Table F9-4 provides an 

estimate of the conservation savings included in each of the six water demand scenarios. The 

conservation savings is calculated based on estimates of what future Colorado River system

water demand would be in these scenarios at 2060 in the absence of decreasing per capita water 

use rates (Technical Report C – Water Demand Assessment provides a complete description of 

the demand scenarios). As shown in the table, the conservation considered in the demand 

scenarios ranges from 300 thousand acre-feet per year (kafy) to more than 1.1 million acre-feet 

per year (mafy) depending on the assumptions within each scenario regarding degree of per 

capita water demand reductions.

TABLE F9-4

Estimated M&I Conservation Savings by 2060 (afy) Included in Demand Scenarios

Current 

Projected

(A)

Economic 

Slowdown

(B)

Expansive 

Growth 

(C1)

Expansive 

Growth 

(C2)

Enhanced 

Environment 

(D1)

Enhanced 

Environment 

(D2)

Estimated Savings 

from 2015 Level

Use Rates

478,000 296,000 621,000 1,048,000 1,052,000 1,114,000

Additional conservation beyond that included in the demand scenarios was considered in the 

three additional conservation levels (Level 1, 2, and 3). The demand reductions from each of 

these levels were computed using the assumptions in table F9-3 applied to the M&I demand over 

the entire Study Area. Estimates of level of demand and conservation potential in residential, 

CII, outdoor landscaping, and water loss were developed based on regional and Study Area 

estimates. The potential conservation was assumed to apply proportional to all M&I demands 

within the Study Area. However, the areas of greatest M&I demand are outside of the 

hydrologic basin and generally include a portfolio of water supplies (groundwater, local supplies, 
Colorado River Basin

Water Supply and Demand Study

F9-10 December 2012

other imports, etc.) including Colorado River water. The supplies each have their own cost, 

reliability, water quality, and other factors that lead to agency preferences related to which 

supply (current or future) would be reduced under lower demand scenarios. Under purely 

financial considerations, it is unlikely that the Colorado River supply is the marginal supply in 

the portfolio. Given the complexity of regional and local water management decisions, it was 

assumed that reductions in Study Area M&I water demand as part of these options are 

distributed proportionally to the magnitude of supplies from the Colorado River and nonColorado River sources. 

Table F9-5 presents the estimated M&I water conservation savings associated with the Level 1, 

2, and 3 assumptions. These values represent the sum of the potential conservation in the Study 

Area for residential, CII, outdoor landscaping, and water loss measures compared to the scenario 

demand at 2060. The last row shows the potential reduction that might accrue to the Colorado 

River demand. The Basin demand reduction is substantially lower because the major urban areas 

are located outside of the hydrologic basin and have diversified portfolios of supplies to which 

the benefits would likely accrue. This aspect is an important consideration in Basin water 

planning. Water conservation in the areas served by Colorado River or tributary water would 

likely have benefits for reducing demand on all supplies in the service areas, but may have a less 

than one-for-one benefit for reducing Colorado River system demands.

The areas of greatest potential for savings are residential indoor and outdoor landscaping water 

conservation measures. Conservation measures within these two categories represent almost 80

percent of the total M&I water conservation potential estimated in this evaluation. 

TABLE F9-5

M&I Conservation Savings (afy) for the Current Projected Scenario by 2060

Level 1 Level 2 Level 3

Study Area

Residential 94,000 532,000 1,110,000

CII 77,000 237,000 362,000

Landscape 164,000 509,000 958,000

Loss 125,000 149,000 174,000

Total 459,000 1,428,000 2,604,000

Colorado River System

Estimated Colorado River System Demand 

Reduction 185,000 576,000 1,051,000

The M&I conservation options included here are based on conservation in addition to that 

already included in the demand scenarios. However, because the Study considers six distinct 

water demand scenarios that have different levels of both passive and active conservation, the 

conservation levels may generate a different magnitude of savings when compared to different 

scenarios. Table F9-6 shows the cumulative potential reduction in Colorado River system 

demand for each of the six water demand scenarios and for each conservation level. For all 
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-11

options, these values represent the additional demand reduction by 2060. The actual demand 

reduction would ramp up over time as conservation measures are applied more aggressively and 

adoption rates are expanded. 

TABLE F9-6

Reductions in Colorado River System Demand (afy) for Each Demand Scenario and Conservation Level at 2060

Conservation 

Level

Current 

Projected

(A)

Slow 

Growth

(B)

Rapid

Growth 

(C1)

Rapid

Growth 

(C2)

Enhanced 

Environment 

(D1)

Enhanced 

Environment

(D2)

Level 1 185,000 187,000 207,000 56,000 44,000 55,000

Level 2 576,000 504,000 681,000 427,000 238,000 383,000

Level 3 1,051,000 888,000 1,258,000 960,000 654,000 908,000

Significant water conservation has occurred in the recent decades through most urban centers in 

the Study Area. The M&I water conservation savings realized in the demand scenarios and 

potential additional measures will likely occur at a lower annual rate than what has been 

observed in recent historical periods due to differing types of conservation measures and greater 

adoption rates that will need to be included. As noted for other options, in order to represent the 

challenges associated with increasing scale, when options exceed a 200 kafy yield, they are 

generally assumed to be implemented in 200-kafy steps. For example, for the Current Projected 

(A) scenario, M&I conservation options would be available in six steps, at 200 kafy each for the 

first five steps and at 51 kafy for the final step. These steps are assumed to proportionally 

implement progressive amounts of the individual levels noted in the table. For example the first 

step of conservation will implement 185 kafy of “Level 1” practices and 15 kafy of “Level 2” 

practices. 

Figure F9-2 shows the resulting Basin-wide savings for the Level 1, 2, and 3 conservation levels 

compared to the Current Projected scenario.
Colorado River Basin

Water Supply and Demand Study

F9-12 December 2012

FIGURE F9-2

Estimated Water Conservation Savings (af) in Current Projected Scenario and Additional Conservation Levels

8.0 Timing of Option Availability

Because the M&I water conservation options would be ramped over time, each of the options 

could begin implementation with benefits starting to accrue within 5 years. The conservation 

program would need to be established, commitments of Basin-wide BMPs, and measures to 

assess per capita water use baselines and performance would be agreed upon before 

implementation. The potential savings of the options would be small in the early years of 

implementation and grow over time. 

Ultimate savings for each level are assumed to occur in 2060, with the savings progressively 

ramping from 2015 through 2060. However, it is possible that adoption rates could be slower or 

faster than those included in the conservation level assumptions. In addition, Conservation 

Level 2 would in all likelihood need to have adopted all Conservation Level 1 measures, and 

Conservation Level 3 would need to have adopted most of the measures and achieved adoption 

rates from Conservation Level 2.

-

200,000 

400,000 

600,000 

800,000 

1,000,000 

1,200,000 

1,400,000 

1,600,000 

1,800,000 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 Savings (ac-ft)

Year

Level 3

Level 2

Level 1

Current Projected
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-13

9.0 Costs

Costs for implementing M&I water conservation vary by measure, location, and timing. The 

BMPs shown in figure F9-3 are intended to represent a range of potential measures for cost 

considerations. This figure presents representative BMPs and their associated costs from the 

Water Use Efficiency Comprehensive Evaluation, (CALFED, 2006). Costs for the options were 

amalgamated by demand type (residential indoor, CII, outdoor, and water loss). It was generally 

assumed that the most cost-effective BMPs would be implemented first, followed by 

progressively more-costly measures. However, suites of BMPs are generally implemented when 

an agency is implementing water conservation programs. For this reason, an average cost of 

various BMP suites was assumed. Based on historical conservation levels within the Study Area, 

it was assumed that foundational BMPs related to education and staffing were largely embedded 

in the demand scenarios and these costs were not included. Conservation Level 1 was assumed 

to be the average cost of available BMPs within the demand type (residential, CII, outdoor 

landscaping, and water loss). Conservation Level 3 costs were assumed to be the average of the 

more-expensive BMPs within the M&I demand type, and Conservation Level 2 costs were 

assumed to be between these costs.

FIGURE F9-3

Average Costs of Various M&I Water Conservation BMPs (dollar per afy)

SF=single family, MF=multi-family Source: CALFED, 2006

These BMPs were grouped by demand type and used to assign costs to the conservation levels. 

In addition, a landscape replacement cost was developed based on a $2 per square foot rebate for 
Colorado River Basin

Water Supply and Demand Study

F9-14 December 2012

xeriscaping 1,500 square feet of turf using the range of information from the Southern Nevada 

Water Authority (2005), the City of Peoria, Arizona (2012) the City of San Diego (2012), and 

Albuquerque Bernalillo County Water Utility Authority (2012) turf conversion programs. These 

costs were amortized at 4.125 percent over 20 years, consistent with other option cost estimates. 

Table F9-7 presents the estimated costs per af of water conservation savings to implement the 

suite of BMPs for each conservation level. The unit annual costs range from roughly $350 to 

$1,400 per afy reduction in demand. CII and outdoor landscaping water conservation measures 

represent the most cost-intensive measures. Based on the assumption that the water conservation 

savings result in proportional savings to all supplies contributing to Study Area delivery, the 

demands for Colorado River system water may only be reduced by about 40 percent of the total 

Study Area demand reduction. However, it was assumed that the cost to Colorado River system 

water users is solely for the reduction (benefit) that they achieved and that “other” beneficiaries 

would pay for their portion of the overall benefit. It is quite possible that M&I water 

conservation in some regions outside of the hydrologic basin may result in little to no reduction 

in Colorado River demand due to cost considerations within the region’s water supply portfolio. 

TABLE F9-7

Estimated Costs per af Demand Reduction for Each Conservation Level at 2060 

Costs (afy) for Demand Reduction by Category

Level 1 Level 2 Level 3

Residential Indoor $ 350 $ 450 $ 550

CII $ 550 $ 900 $ 1,200

Outdoor Landscape $ 700 $ 1,050 $ 1,400

Water Loss $ 350 $ 350 $ 350

Total $ 500 $ 750 $ 950

Per capita water use varies widely across the states and across planning areas within states 

because of differences in climate conditions, economic and demographic conditions, industry 

and recreation composition, and level of historical conservation efforts. The conservation 

options described here are applied as a Basin-wide percent reduction in M&I demand. It should 

be recognized that in reality some regions could achieve the targets more cost- effectively than 

regions that have had active conservation programs in place for several decades.

10.0 Other Key Criteria

In addition to yield, timing, and cost, the M&I conservation options were characterized for 

several other criteria. A summary of the findings for all criteria is shown in table F9-8. In 

general, these options are highly feasible, with existing examples in areas of the Southwest and 

in other arid regions of the world. Programs of this scale are underway at state levels, but have 

not been demonstrated on basins of the scale of the Colorado River in North America. Based on 

the targeted BMPs and quantity of yield, these options are likely to become progressively more 

difficult to implement moving from Level 1 to Level 3. Likewise, as conservation becomes 

more successful, the ability to reliably maintain a given level becomes somewhat more difficult 
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-15

through the result of demand hardening – less discretionary use. It is not anticipated that 

permitting or legal changes will be required to implement most conservation measures, but 

agreements will be required on the methodology and institutional structure to implement in this 

multi-jurisdictional Basin. Some policy changes may be required to fully implement the Level 3 

assumptions depending on implementation, in that large-scale landscape conversion to xeriscape 

will be required. There is some implementation risk in that yields will fluctuate over time, and 

programs will require continuous funding to maintain overall results. Many conservation 

measures are based on achieving behavior changes in the way water is valued and used. The 

realized conservation savings associated with these measures may depend on future economic, 

social, and political conditions that maintain and strengthen these behavior changes. In general, 

however, once savings are realized through most measures they can be maintained, resulting in 

long-term viability of the options. These options were rated high with respect to operational 

flexibility because the programs can be stopped at any time without incurring significant debt 

service or resulting in stranded assets. There are no inherent energy needs for the M&I 

conservation options in that they result in reduced demand and reduced need to treat and deliver 

water. For the highest levels of conservation there could be some socioeconomic issues as turf is 

replaced by xeriscaping. 

11.0 Characterization Results

A summary of the characterization findings are shown in table F9-8. The top portion of the table 

shows the estimated quantity of yield, earliest timing of implementation, and estimated cost. The 

bottom portion of the table shows the 17 criteria and associated ratings (“A” through “E”) for 

each option. As noted previously, for implementation purposes, some large options, were broken 

into 200-kafy yield steps to reflect increasing complexity as project size increases. For 

conservation, the three conservation levels resulted in demand reduction (yield) from about 

600,000 afy to 1.2 mafy. These resulting yields were implemented in 200-kafy steps. These 

steps are denoted numerically with “1” being the first 200-kafy step, followed by subsequent 

steps. In general, a “C” rating is typically designated as mostly neutral (yellow), “A” is largely 

positive (green), or easier to accomplish, and “E” is largely negative (red) or more difficult to 

accomplish. Refer to appendix F3 for specific criteria descriptions and rating scales.
Colorado River Basin

Water Supply and Demand Study

F9-16 December 2012

TABLE F9-8

Summary Characterization Ratings for M&I Conservation Options
Appendix F9 — Option Characterization –

Municipal and Industrial Water Conservation

December 2012 F9-17

12.0 References

Albuquerque Bernalillo County Water Utility Authority. 2012. Retrieved August 2012 from 

http://www.abcwua.org/content/view/132/222/

American Water Works Association Research Foundation. 1999. Residential End Uses of 

Water. 

Aquacraft. 2011. Analysis of Water Use in New Single Family Homes. 

Arizona Department of Water Resources. 2008. Third Management Plan, 2000–2010, modified 

2008.

CALFED. 2006. Water Use Efficiency Comprehensive Evaluation.

California Urban Water Conservation Council (CUWCC). 2005. BMP Costs & Savings Study: 

A Guide to the Data and Methods for Cost Effectiveness of Urban Water Conservation 

Best Management Practices. 2005 Revision.

California Urban Water Conservation Council (CUWCC). 2011. Memorandum of 

Understanding Regarding Urban Water Conservation in California. Amended 

September 14, 2011. 

California Department of Water Resources. 2010. 20x2020 Water Conservation Plan.

City of San Diego. 2012. Retrieved August 2012 from 

http://www.sandiego.gov/water/conservation/residentialoutdoor.shtml

City of Peoria AZ. 2012. Retrieved August 2012 from 

http://www.peoriaaz.gov/newsecondary.aspx?id=1277.

Colorado Water Conservation Board (CWCB). 2011. SWSI 2010 Municipal and Industrial 

Water Conservation Strategies.

Metropolitan Water District of Southern California (MWD). 2010. Integrated Water Resources 

Plan 2010 Update, Technical Appendix.

Pacific Institute. 2011. Municipal Deliveries of Colorado River Basin Water. June. 

Southern Nevada Water Authority. 2005. Xeriscape Conversion Study Final Report.

U.S. Environmental Protection Agency (EPA). 1998. Water Conservation Plan Guidelines. 

Appendix F10

Option Characterization – 

Agricultural Water Conservation

December 2012 F10-1 

Appendix F10 — Option Characterization – 

Agricultural Water Conservation 

1.0 Introduction

Agricultural water conservation has been proposed to reduce the overall water demand in areas 

currently relying upon water supply from the Colorado River system. Nine options related to 

agricultural water conservation were submitted for consideration in the Colorado River Basin 

Water Supply and Demand Study (Study). These options were used to develop agricultural 

water conservation representative options. The representative options were parsed into 200 kafy 

“steps” to represent likely project phasing. The submittals are summarized in appendix F2 and 

the original submittals are available via links from the electronic version of appendix F2 on the 

compact disc that accompanies this report and the version of appendix F2 on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html. 

This appendix summarizes the types of options received, categorizes the types of options into the 

following two categories, explains the methods to characterize the options, and provides the draft 

characterization results. 

• Basin-wide agricultural water conservation

• Basin-wide agricultural water conservation with water transfers

Additional detail related to the options characterization is included in appendix F3. Attachment 

A of appendix F3 contains more detailed descriptions of the ratings. Attachment B provides the 

methods used for completing the unit cost calculations. Attachment C presents the detailed 

characterization information and is available on the compact disc that accompanies this report

and on the Study website.

2.0 Overall Approach

Nine options were submitted related to agricultural water conservation to reduce the demand in 

areas receiving Colorado River system water supply. These options ranged in type from specific 

conservation measures or best management practices (e.g., improved irrigation efficiencies, 

modernization, conveyance system efficiencies, changes in types of crops under irrigation, etc.) 

to general implementation approaches that could be used to achieve further water conservation 

(e.g., water pricing or water transfers). 

The concepts received were first organized into six Colorado River Basin (Basin) -wide 

agricultural water conservation measures reflecting different types of activities that could 

generate water savings in the agricultural sector. The six agricultural water conservation 

measures consist of: 

• Advanced irrigation scheduling 

• Deficit irrigation

• On-farm irrigation system improvements

• Controlled environment agriculture 
Colorado River Basin

Water Supply and Demand Study

F10-2 December 2012

• Conveyance system efficiency improvements

• Fallowing of irrigated lands 

Each conservation measure was first evaluated for potential water savings, and then a potential 

percentage reduction in irrigation diversions and/or consumptive use was estimated. Projected 

conserved water yields created by reducing depletions to the Basin were restricted to measures 

that specifically reduce consumptive use for irrigated areas located within the Basin but 

considered total reduction in diversions (consumptive and non-consumptive uses) for irrigated 

lands served outside of the Basin. Each conservation measure was then evaluated in terms of 

potential adoption rates to estimate the total water yield. 

In order to encourage adoption of the targeted water conservation measures, two possible 

implementation approaches were considered: (1) Basin-wide agricultural water conservation 

through a federal or state incentive-based program to encourage agricultural water use efficiency 

without specific legal transfer of water or water rights, and (2) Basin-wide agricultural water 

conservation with water transfers between a willing transferor and willing transferee that 

promotes water conservation and/or short-term or permanent fallowing of irrigated lands to 

transfer conserved water to the transferee for a similar or different use. 

For purposes of this analysis, each of the various conservation measures were examined as a 

Basin-wide potential, but in reality the measures will have important regional limitations and in 

some cases may be mutually exclusive. Some of the various measures should not be considered 

to be additive. Nevertheless, they are broken out in the following sections for the reader to 

understand the basic assumptions used in the option characterization. 

Because levels of current agricultural conservation measures vary throughout the Study Area, 

different levels of potential savings are possible for a given conservation measure. These 

savings range from essentially no savings where measures have been fully adopted to significant 

savings where measures have not been adopted or where adoption rates are relatively low. 

Disaggregating the savings potential by conservation measure and individual location was 

beyond the scope of this Study. In addition, the conservation measures could produce different 

amounts of savings depending on the location in the Basin, implementation approach, and 

combination of measures; therefore, the total quantities are estimated as an aggregate for each 

implementation approach. Up to 1 million acre-feet per year (mafy) of potential savings by 2060 

was considered for both approaches (incentive-based program and water transfers) combined 

with roughly 500,000 acre-feet per year (afy) potential under each approach category. Note that 

the categories are considered separately largely because the types of reductions are mutually 

exclusive (i.e., on-farm reductions produce no savings to a fallowed field.) The representative 

options reflect additional water conservation above and beyond existing water conservation 

programs that are already included in the demand scenarios in the Study. 

3.0 Potential Agricultural Water Conservation Measures 

Each of the potential agricultural water conservation measures that were considered in the 

analysis are generally described below. Additional detail on expected quantity of yield, timing 

of option availability, and costs are provided in later sections. 
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-3 

3.1 Advanced Irrigation Scheduling

This measure involves the application of advanced irrigation scheduling techniques using local 

climate and soil moisture information to match water deliveries with crop water needs more 

precisely. In areas of elevated water and/or soil salinity, it also involves the application of soil 

salinity and crop salt-tolerance monitoring to determine necessary irrigation leaching fractions

more precisely. This measure has potential to reduce total water diversions, but is not likely to 

provide significant reduction in consumptive use. 

3.2 Deficit Irrigation

Like the advanced irrigation scheduling measure, the deficit irrigation option involves water 

management techniques that do not rely on any changes in irrigation infrastructure. This 

measure also requires application of advanced irrigation scheduling practices but takes advanced 

scheduling one step further to impose water stress on crops during drought-tolerant growth 

stages, with the goal of maximizing crop water productivity or maximizing farm-gate 

profitability with marginally reduced crop yield. Deficit irrigation has the potential to reduce 

both water diversions and consumptive use. In areas in the Upper Basin and adjacent areas that 

experience significant physical supply shortages, deficit irrigation is not expected to result in 

reduced basin water consumption or need for Colorado River water because under existing state 

water laws additional water will be available to reduce shortages to other Basin water users. As 

described in this appendix, this measure does not include significant under-irrigation to the point 

of reducing yields by more than 20 percent or substantially reducing farm-gate profitability. 

Compensated programs for significant deficit irrigation of permanent forage crops such as split 

season fallowing are addressed separately under the irrigated lands fallowing water conservation 

measure. 

3.3 On-farm Irrigation System Improvements

On-farm irrigation system improvements such as conversion from flood to sprinkler and/or drip 

irrigation methods are included in this measure. Although consumptive use savings are not 

expected for this conservation method, reductions in total water diversions from reduced 

tailwater and deep percolation return flows can be expected with appropriate controls on the 

conservation program implementation approaches. 

3.4 Conveyance System Efficiency Improvements

Improvements in conveyance system efficiency through delivery canal lining, canal to pipe 

conversion, improved canal control and/or construction of regulation reservoirs to reduce canal 

operational spills, and implementation of system-wide drainwater or tailwater recovery systems 

are included in this option. Although these conservation methods can yield significant 

reductions in total diversions in many cases, consumptive water use savings are far less and are 

attributed to evaporation, seepage, drainage, and operational spills to saline sumps, bodies of 

water, and phreatophyte evapotranspiration loss from irrigation and drainage canals. 

3.5 Controlled Environment Agriculture

Controlled environment agriculture consists of agricultural production within large-scale 

greenhouses that optimize crop production and reduce water usage by controlling the 
Colorado River Basin

Water Supply and Demand Study

F10-4 December 2012

environment (temperature, relative humidity, etc.) and continuously recirculating water. The 

high associated capital and operation and maintenance cost is the primary barrier to 

implementation of this option. 

3.6 Irrigated Lands Fallowing

Rotational or permanent fallowing is a common practice that is used to effectively reduce crop 

consumptive use when water supplies are limited. This practice is commonly applied when 

economic conditions dictate necessary changes in crop production or for the purposes of: selfregulated water management to fit crop selection and planting areas to within available water 

supplies, water transfers to reallocate water to other non-agricultural uses, and enrollment of 

highly erosive or ecologically sensitive cropland in federal programs. Also considered under this 

option are split season fallowing of permanent forage crops, such as alfalfa. In agricultural areas 

in the Upper Basin and adjacent areas that experience significant physical supply shortages, 

irrigated lands fallowing is not expected to result in reduced Basin water consumption or need 

for Colorado River water because under existing state water laws additional water will be 

available to reduce shortages to other Basin water users.

3.7 Other Considered Options

Some agricultural water conservation options that were submitted for consideration were not 

considered viable methods for achieving water savings. One example is changing the types of 

crops that are grown within the Basin. The types of crops that are grown in the Basin depend on 

a wide array of factors, including local production conditions (climate, soils, water), local and 

global market conditions (supply, demand, and pricing), existing crop- specific infrastructure 

(farm harvest equipment and food processing facilities), and the local price of inputs (labor, fuel, 

water, etc.). Without control of crop selection on all lands within the Basin, payment or 

incentives to change cropping in one area could shift the production of the replaced high-wateruse crop to another location within the Basin, thereby simply shifting the location of water 

depletion but not reducing the overall Basin water use.

4.0 Regional Considerations

The potential agricultural water conservation measures are assumed to apply to the overall Study 

Area, but significant differences in potential water savings between in-Basin in certain areas and 

in adjacent irrigated areas due to water budget considerations and downstream uses dependent on 

return flows. In addition, applied water requirements and evapotranspiration vary across the 

Basin depending on elevation, climate, soils, irrigation methods, crop types, and other factors. 

The Study approach considered in-Basin and adjacent area differences as well as broad 

differences in applied water requirements, but was not planning area- or state-specific in its 

assessment. The total irrigated areas used in these calculations were 2.1 million acres for inBasin lands and 2.5 million acres for adjacent lands, as noted in Technical Report C – Water 

Demand Assessment. For some conservation measures and some regions, significant investment 

has already occurred, and the ability to achieve additional conservation will be limited or more 

costly. For instance, the 0.45 million acres within the Imperial Irrigation District (IID) are 

already involved in an aggressive water conservation program and have been removed from the 

estimates of future agricultural water conservation potential (IID, 2007). 
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-5 

5.0 Implementation Approaches

The two primary implementation approaches under consideration for agricultural water 

conservation are incentive-based programs and water transfers. For either approach, programcontrols are necessary to ensure that water conservation investments provide measurable returns 

in verifiable water savings. Water conservation program controls should address the following 

issues:

• Conserved water needs to be measurable by a reduction in demand, conservation measures 

need to be easily observable, and, where costs are not prohibitive, should be verified by 

volumetric water use measurement. 

• Legal mechanisms must be in place to protect conserved water in-stream for intended uses, 

especially in areas where insufficient stream flow currently limits downstream water users 

from exercising their full diversion rights. 

• Controls may be needed to prevent expansion of effectively irrigated areas associated with 

water conservation investments. 

• Continuing to maintain a healthy agricultural economy and development of associated policy. 

A key distinction between incentive-based programs and water transfers as defined here is 

whether a legal transfer of water or water rights is involved. The incentive-based programs are 

assumed to be accomplished without legal transfer of water or water rights, whereas the water 

transfers specifically revolve around legal transfers of water or water rights.

5.1 Incentive-based Programs

Incentive-based programs can take different forms depending on the type of water conservation 

option and the type of collaborator (e.g., water user versus water purveyor). Generally, this 

option involves providing financial incentives through: 

• Grants or low-interest loans to construct infrastructure projects. 

• Cost-share payments to offset the costs of irrigation system conversion. 

• Incentive payments to growers who adopt water conservation practices and provide 

documentation of management practices (payments to implement specific observable 

practices). 

• Incentive payments based on a reduction in volume of water diverted or consumptively used 

(no specific practice is required, but savings must be measured relative to a baseline). 

• Water pricing reform. 

Several existing federal incentive programs could be applicable under this approach. Potentially 

applicable programs administered by the U.S. Department of Agriculture (USDA) as of the time 

of publication of this appendix include the Environmental Quality Incentives Program, 

Agricultural Water Enhancement Program, Conservation Reserve Program, and Conservation 

Reserve Enhancement Program. Potentially applicable programs administered by Bureau of 

Reclamation (Reclamation) include the WaterSMART Grants, Water and Energy Efficiency 

Grants, and Title XVI Grants.
Colorado River Basin

Water Supply and Demand Study

F10-6 December 2012

5.2 Water Transfers

Water transfers can represent the legal transfer of water or water rights from one use to another. 

Within an agricultural water use framework, transfers can be implemented on a temporary basis 

(one growing season) from year to year or on a permanent basis, essentially through the 

acquisition of water or a permanent water right. Typically, water transfers are negotiated on a 

willing-transferor, willing-transferee basis within a state and can be implemented on a direct 

transferor-transferee arrangement or facilitated through a water bank. Payments can be based on 

measured volume of reduction in diversion or consumptive use or can be tied to observed 

practices, such as land fallowing or forbearance of all diversion. Within a state, priority systems 

for the use of water can affect the ability to implement a water transfer absent the consent of 

intervening priority users. State water laws generally protect agricultural water transfers and 

ensures the historical consumptive use is available for the new use.

6.0 Quantity of Yield

All of the quantification methods for agricultural water conservation are best described in the 

context of overall water balance. Agricultural water use may remove all or a portion of the water

diverted permanently from the watershed, or it may simply reroute a portion of the water by 

changing the pathway, timing, and in many cases, the quality of water as it flows through the 

Basin. The portion of water that is diverted from the streams, used for irrigation, and lost for the 

purpose of other downstream water uses is called consumptive use. It includes transpiration by 

crops and other plants, evaporation from water and soil surfaces, and water flows into saline 

water bodies that cannot be economically recovered. There is another portion of water that is 

diverted from the streams and used for irrigation, but which returns to the streams either directly 

through surface runoff or groundwater return flows. These return flows are subject to additional 

use and appropriation by downstream water users. 

Because irrigated lands both inside and outside the Basin are served with Colorado River water, 

the accounting of water savings must address the differences in depletion to Basin water supply 

within these two regions. All water exported from the Basin is lost permanently from additional 

use within the Basin, even though only a portion is consumptively used by crops, and is 

considered depletion. Within the Basin, only consumptive use is considered depletion. The 

methods used to quantify potential yield from agricultural conservation all distinguish between 

conserved water that would have been lost to the Basin versus conserved water that is simply rerouted within the Basin. Generally, any savings in water that would have been exported from the 

Basin is counted as reduced depletion and therefore potential yield; within the Basin, only 

reductions in consumptive uses reduce depletion and can thus be counted as potential yield.

Although re-routed water within the Basin may not appear to produce yield from the perspective 

of the Basin’s water balance, it can still have important value for improving the location, timing, 

and quality of flows. However, in many cases re-routed return flows can adversely affect other 

uses of the water that relied on the current flow paths and timing. Current water law in Colorado 

addresses this issue through only allowing an irrigator’s historical consumptive use to be 

transferrable for other uses (Colorado Agricultural Water Alliance, 2008). These effects are 

captured in the evaluation criteria (legal, water quality, other environmental, and 

socioeconomic). 
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-7 

Due to the over-allocated and "supply-limited" nature of irrigation water use in the Upper 

Division States (Colorado, New Mexico, Utah, and Wyoming), and the high degree of sequential 

reuse of return flows, it is expected that agricultural water conservation savings in these areas 

will be limited by downstream return flow-dependent uses. For a given funded water 

conservation project, a portion of the field-scale water savings will likely be demanded by junior 

downstream users that have historically relied on these return flows. Exceptions to this condition 

will occur in the most downstream areas of irrigation projects where downstream ability to reuse 

return flows in other areas is limited. Additionally, there may be distinctions between surface 

and groundwater return flow impacts, with downstream users being more immediately and 

directly dependent on surface return flows. The estimated quantities of yield and cost per acrefoot (af) of water conserved are based on field-scale estimates and are not discounted for return 

flow-dependent uses until the final summary table. 

Furthermore, the Colorado River Simulation System (CRSS) model used to evaluate system 

reliability does not directly represent a significant number of the tributaries in Colorado, 

Wyoming, Utah, and New Mexico. In Colorado, for example, inflow nodes are only included for 

the main stem Colorado, Gunnison, Yampa, San Juan, and White rivers. Demands upstream of 

these inflow nodes are aggregated and represented at those same locations. A significant portion 

of the aggregated irrigation demands divert from the smaller tributaries and are unable to receive 

a full water supply during the irrigation season either because of physical flow limitations or the 

need to bypass water to satisfy downstream senior demands. 

Because of CRSS model limitations, supply-limited consumptive use is used to represent 

irrigation diversion demands in CRSS. Because smaller tributary demands are represented on 

the main stem of the largest rivers in the Upper Basin, CRSS model may inaccurately show that 

full-supply demands could be satisfied. This would overstate consumptive uses. It should be 

clearly noted that the use of supply-limited demands (instead of potential crop demands) 

understates both demands and associated shortages due to CRSS model limitations. The use of 

supply-limited demands is consistent with the consumptive uses and losses reported values as 

well as the 2007 Upper Colorado River Commission depletion schedule estimates.

6.1 Estimates by Conservation Measure

The estimated quantities of yield, before discounting for the effect of return flow-dependent use, 

are discussed in this section for each of the agricultural water conservation measures. Table F10-

1 summarizes the percent reduction in consumptive use and percent reduction in total diversions 

associated with implementing a unit amount of each measure. These estimates are explained in 

the following sections. 
Colorado River Basin

Water Supply and Demand Study

F10-8 December 2012

TABLE F10-1 

Estimated Potential Water Savings Percentages at the Farm Scale for Each Agricultural Water Conservation Measure

Water Conservation Measure

Reduction in 

Consumptive Use 

(In-Basin)

Reduction in Total 

Diversion

(Outside Basin)

Advanced Irrigation Scheduling 0% 13%

Deficit Irrigation 13% 20%

On-farm Irrigation System Improvements 0% 20% 

Conveyance System Efficiency Improvements 1% 20%

Controlled Environment Agriculture 50% 50%

Irrigated Lands Fallowing 40 to 100% Up to 100%

Water savings for reductions in total diversion have not been discounted for effects of return flow-dependent 

use. 

Generally, the estimates of potential water savings from each water conservation measure were 

made by multiplying the potential percent reduction in consumptive use (in-Basin) and total 

diversions (outside Basin) by the estimated consumptive use and diversions within each Basin 

state1 from the 2060 CRSS simulation results and finally, multiplying by an estimated adoption 

rate. In estimating adoption rates, it was considered that some fraction of water users are already 

implementing the conservation measure and some fraction of the remaining water users would 

not be receptive to the measure. For instance, if 50 percent of irrigators were using flood 

irrigation and it was estimated that 50 percent of those irrigators would engage in a program to 

upgrade on-farm irrigation systems to drip or sprinkler, the overall adoption rate would be 

25 percent.

6.2 Advanced Irrigation Scheduling

Advanced irrigation scheduling focuses on improved water management methods that typically 

do not require physical changes or improvements to irrigation system equipment. Estimates of 

the potential reduction in applied water from improved irrigation scheduling and soil salinity 

management were taken from Eching (2002) as reported in Cooley et al. (2008), who found a 13 

percent reduction in applied water and 8 percent increase in yield resulting from the use of 

advanced irrigation scheduling by 55 growers across California. The Imperial Irrigation District

Efficiency Conservation Definite Plan (IID, 2007) estimated between 0.2 and 0.38 acre-feet (af)

per acre reduction in applied water from different ways of implementing irrigation scheduling. 

When compared to the average irrigation applied water amount within IID of about 5.1 af per 

acre (IID, 2007), this represents an applied water savings of 4 to 8 percent. For the purposes of 

this discussion, the 13 percent water savings estimate is used for reduction in applied water only. 

For in-Basin implementation, the consumptive use reduction benefit of this option was 

assumed to be zero. As reported by Eching (2002), increased yields were also associated 

with the reductions in applied water through advanced irrigation scheduling. This can 

 

1 Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming. 
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-9 

occur when water deliveries are more closely matched to periods of crop water demand, 

thereby reducing water stress and increasing crop yields and crop consumptive use. 

For purpose of water savings estimates, 25 percent of all irrigated acres outside the basin were 

assumed to adopt irrigation scheduling. Based on these assumptions, about 270,000 afy of 

depletions from the Basin could be reduced. 

6.3 Deficit Irrigation

Deficit irrigation has been defined in multiple ways (Smith, 2011). However, for purposes of 

this analysis, the definition presented by Geerts and Raes (2009) has been adopted, where deficit 

irrigation is “deliberately tolerating drought stress for maximizing the productivity of water”. 

Stated another way, deficit irrigation is minimizing water use while maintaining crop yield or 

maximizing crop yield per unit of water use. 

Deficit irrigation has been demonstrated to reduce water use by about 20 percent and maintain or 

improve yield and crop quality on almond and pistachio crops in California (Goldhamer et al., 

2006). Deficit irrigation of grain crops such as winter wheat has also been shown to maintain or 

improve overall farm-gate profitability with reduced irrigation and subsequent marginally 

reduced grain yield (English and Nakamura, 1989). On-farm research in the Columbia River 

Basin demonstrated that the optimum farm net income occurred with irrigation water use 

reductions of 20 to 30 percent on winter wheat (English, 1990) and that crop consumptive use 

was reduced by about 13 percent with a 20 percent reduction in applied water (English and 

Nakamura, 1989). The most profitable level of stress irrigation will depend on crop prices 

relative to irrigation costs, and growers are often reluctant to stress irrigate due to the risk of 

over-stressing and causing too much loss in yield. Nevertheless, these studies indicate a large 

potential for deficit irrigation while maintaining profitable agriculture.

Deficit irrigation research being conducted by the USDA Agricultural Research Service in 

Greeley, Colorado has documented water use and crop yield relationships for a number of field 

crops including corn, wheat, sunflower and dry beans (Trout and Bausch, 2012). This

information has been used by the Northern Colorado Water Conservancy District (Altenhofen, 

2012) to establish farm gate economics of deficit irrigation for these crops and to establish 

possible incentive payments to compensate for projected yield losses. For example, deficit 

irrigated corn with 80 percent of maximum yield at a 50-percent reduction in consumptive use 

would require an annual incentive payment of about $150 per af with corn at $4 per bushel. 

For purposes of estimating potential savings, it was assumed that 50 percent of orchards, 

vineyards, small grains, corn, and sunflower acreage would adopt deficit irrigation. Without 

detailed cropping information on all lands irrigated with Colorado River system water, general 

crop percentages reported within the 2007 agricultural census for the Basin States was utilized

(USDA, 2007). The census data indicate that no more than about 1 percent of land irrigated with 

Colorado River system water is in orchards or vineyards. The census data also indicate that 

small grains (wheat, barley, oats, rye) accounts for about 6.3 percent and irrigated corn accounts 

for 3.2 percent of total harvested cropland within the Basin. Using the 2011 crop production 

summary from the National Agricultural Statistics Service (2011), sunflowers were harvested on 

about 100,000 acres in Colorado in 2011, which represents about 1.4 percent of the total Basin 

irrigated acres within the planning area. Based on these land area percentages totaling 11.9 
Colorado River Basin

Water Supply and Demand Study

F10-10 December 2012

percent, the 50 percent adoption rate assumptions, and the per-acre water savings estimates, the 

potential water saving from applying deficit irrigation to the selected crops is estimated to total 

about 130,000 afy. 

As noted above, in areas in the Upper Basin and adjacent areas that experience significant 

physical supply shortages, deficit irrigation is not expected to result in reduced Basin water 

consumption or need for Colorado River water because under existing state water laws additional 

water will be available to reduce shortages to other basin water users. Therefore, when this 

option is included in a portfolio, the portion of the 130,000 af water savings in the Upper Basin 

will be used directly to reduce other Upper Basin users’ shortages, both within the Basin and in 

adjacent areas.

6.4 On-farm Irrigation System Improvements

On-farm irrigation efficiency is typically defined as the water consumed through crop 

consumptive use divided by the total irrigation water applied. Flood irrigation methods in 

general tend to operate at lower on-farm irrigation efficiencies than sprinkler or drip irrigation 

methods because of higher volumes of surface runoff (tailwater), subsurface runoff (tilewater), 

and deep percolation (groundwater return flow). However, while converting from flood to 

sprinkler or drip irrigation methods reduces total diversions, it is not likely to reduce 

consumptive use significantly and could actually increase consumptive use in some instances. 

This results from increased evaporation with sprinkler methods and increased crop 

evapotranspiration with improved water distribution uniformity. On the basis of reduced 

depletions divided by investment costs, the cost of converting from flood to sprinkler or drip 

within the Basin was considered too high to justify for water supply mitigation due to the 

marginal to negative consumptive use benefits. However, benefits for out-of-Basin application 

of on-farm irrigation system improvements could be significant (where return flows can be 

adequately addressed) and were included in the analysis where reductions in total irrigation 

diversion could be counted as water savings. It was recognized in this analysis that incentives 

for converting flood irrigation to sprinklers are already being provided in the Basin for water 

quality enhancement through the Colorado River Basin Salinity Control Program. However, the 

basis for funding those projects is not for water supply mitigation but rather to reduce deep 

percolation and groundwater return flows from agricultural lands that mobilize salts into the 

Colorado River and its tributaries (Reclamation, 2011). 

Reductions in total irrigation diversions at a field scale were estimated by comparing typical onfarm irrigation efficiency levels. Using an average flood irrigation efficiency level of 70 percent 

and assuming that center pivot irrigation and drip irrigation could achieve an efficiency level of 

87 percent (WDOE, 2005), the assumed reduction in total diversion is 20 percent. Assuming that 

10 percent of irrigated land outside of the Basin is converted from flood to drip and 20 percent 

from flood to sprinkler (pivot), this option may reduce agricultural consumptive use by up to 

490,000 afy. However, 270,000 afy of these potential savings occur in Colorado, where current 

administrative practice does not allow reallocation of water saved due to improved efficiency 

(Colorado Agricultural Water Alliance, 2008). 

This option requires a flow meter to be installed and the grower to follow an irrigation water 

management plan written for operations of the revised system in order for savings to be realized. 

The option may also require controls that limit the effective irrigated area to no greater than 

historical effective irrigated areas considering distribution uniformity effects.
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-11

6.5 Conveyance System Efficiency Improvements

Conveyance system efficiency improvements were estimated by considering the potential for 

canal lining, canal to pipe conversion, improved canal control and/or construction of regulation 

reservoirs to reduce canal operational spills, and system-wide implementation of drainwater or 

tailwater recovery systems in order to reduce evaporation, seepage, operational spills, and 

phreatophyte evapotranspiration losses. The majority of water savings through these actions 

simply change the redistribution of water because the seepage and other surface return flows 

often become supply for other water uses in the Basin. Ignoring surface and groundwater 

recharge losses to saline sumps or bodies of water, reductions in direct canal evaporation and 

phreatophyte evapotranspiration losses along canals, drains, and wasteways are the only effective 

mechanisms for reducing consumptive use for in-Basin agricultural water savings through this 

method. 

Potential water savings through conveyance system efficiency improvements will vary widely 

from project to project depending upon the baseline system infrastructure and operations. 

Systems that have already undergone significant conveyance system efficiency projects will have 

less potential to yield additional water savings than those continuing to operate with older and 

less-advanced systems. For the basis of making potential water savings estimates, system-wide 

water budget estimates from the Imperial Irrigation District Efficiency Conservation Definite 

Plan (IID, 2007) were used. For an improvement project that eliminated main canal and lateral 

spill, canal seepage and net evaporation and reduced on-farm tailwater by 80 percent, the 

potential reduction in water diversions is estimated at 20 percent and the reduction in 

consumptive use through eliminating canal evaporation is 1 percent of water diversion. 

Assuming that half (50 percent) of the irrigation systems receiving Colorado River water outside 

the Basin could achieve this level of reduction, the potential water savings of this option has 

been estimated at approximately 820,000 afy. However, 450,000 afy of these potential savings 

occur in Colorado, where current administrative practice does not allow reallocation of water 

saved due to improved efficiency (Colorado Agricultural Water Alliance, 2008). 

6.6 Controlled Environment Agriculture

Water savings in controlled environment agriculture are largely achieved by recirculating water 

within the greenhouse environment and by producing higher yield per unit of cropped area. 

However, greenhouse production is expensive and has been demonstrated to be commercially 

viable only for horticultural crops such as fresh market vegetables and nursery plants. Further, 

commercial viability depends on either producing superior quality crops or bringing crops to 

market during times of year when field production is not feasible. Capital costs can exceed 

$200,000 per acre (Tatum and Hood, 2009), compared to less than a tenth of that for facilities to 

support field production. Estimates of water savings vary widely. On the low end, there are 

estimates of greenhouse water use being 5 percent of outdoor water use on a volume used per 

unit crop output basis (Sandia, 2005); however, these estimates are from short field studies 

during cool times of the year and do not capture a full annual cycle. Estimates of water use for 

greenhouse produced tomatoes were about 17 percent of outdoor water use, calculated as volume 

used per pound of crop produced (Sandia National Labs, 2005). However, other studies 

comparing monitored greenhouse water use with outdoor cultivation water use (e.g., Mpusia, 

2006) showed greenhouse water use as 65 percent of that for outdoor cultivation. For the 

purposes of the Study, a water savings of 50 percent over traditional outdoor cultivation was

assumed for controlled environment agriculture. 
Colorado River Basin

Water Supply and Demand Study

F10-12 December 2012

2007 census data for the Basin States indicate that vegetable acreage ranges from about 

0.1 percent to over 4 percent of crop acreage, depending on the state (USDA, 2007). Applying a 

2 percent vegetable crop acreage to estimated irrigated acreage, land potentially suitable for 

greenhouse production is estimated to be about 42,000 acres within the Basin and 50,000 acres 

out of the Basin. Much of this land both in and out of the Basin is in warm winter areas that 

already enjoy significant cost and market advantages for field production; growers in these areas 

would have limited incentive to incur the significant cost for greenhouse production except on a 

limited basis. Assuming that about 10 percent of the vegetable acreage irrigated with Colorado 

River water (9,000 acres) could be profitably converted to greenhouse production, and that the 

total water consumption could be reduced by 50 percent, the total amount of water saved would 

be approximately 13,000 afy. Based on estimates from the University of Arizona (Controlled 

Environment Agriculture Center, 2012), the total area under greenhouse production across the 

entire United States is currently about 21,000 acres. Consequently, this effort would involve 

increasing the U.S. greenhouse production by more than 40 percent from current levels.

6.7 Irrigated Lands Fallowing

Irrigated lands fallowing is one of the most direct and simple methods of irrigation water 

conservation in terms of water accounting and accepted legal frameworks allowing reallocation 

of conserved water. However, this practice can have significant impact on local economies 

where implemented. Examples of significant fallowing programs for water conservation can be 

found in the IID and the Klamath Basin, among others. 

The most common application of this water conservation method is with annual crops. However, 

temporary fallowing and split-season leasing of water rights for permanent forage crops such as 

irrigated pasture have also been implemented with varying degrees of success. The Klamath 

Basin Rangeland Trust (KBRT) has an active split-season leasing program focused on curtailing 

water deliveries to irrigated pasture in the mid- to late- summer irrigation period (KBRT, 

2011).The Colorado water bank has also considered split-season fallowing for irrigated pasture 

and hay production, but several operational and perception challenges need to be overcome with 

participants, as presented by Gangwer (2011). 

The amount of conserved water yielded from fallowing can vary widely depending upon the 

crop, season of fallowing, and site climate and soil/groundwater conditions. For summer annual 

crops in dry regions with little summer rainfall or access to shallow groundwater, the 

consumptive use savings can be nearly 100 percent of the consumptive use under irrigated 

conditions. For permanent crop applications with access to shallow groundwater, the savings 

can be far lower. For example, measured consumptive use on irrigated and non-irrigated grass 

pasture in the Klamath Basin has demonstrated a reduction in consumptive use of about 1 mafy

(KBRT, 2005) in a location where the annual consumptive use under irrigation is approximately 

2.58 mafy, for a savings of 39 percent of irrigated consumptive use. For this reason, the 

potential water savings have been estimated as 40 to 100 percent of consumptive use within the 

Basin and up to 100 percent of total diversions. 

This option has been conceptualized as an overall Basin-wide program (or a set of planning area 

programs) consisting of rotational or permanent fallowing. Such a program would be scalable 

over time and could be sized to achieve any level of reduction in consumptive use. Constraints 

on the size of the program would likely be influenced primarily by economic considerations; for 

example, the level of reduction in consumptive use in a particular planning area could be scaled 
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-13

to maintain a viable agricultural economy and avoid unacceptable impacts on jobs. For planning 

purposes, the amount of savings is assumed to be up to 10 percent of the irrigated lands and 

10 percent of the agricultural consumptive use in the water demand scenarios. Applying this 

reduction percentage to the 7.2 mafy consumptive use within the planning area, it was assumed 

that up to 720,000 afy of water savings could be generated from fallowing measures, but this 

would be limited to water transfer programs with legal transfer of water or water rights 

(temporary or permanent). 

As noted above, in areas in the Upper Basin and adjacent areas that experience significant 

physical supply shortages, irrigated lands fallowing is not expected to result in reduced Basin 

water consumption or need for Colorado River water because under existing state water laws 

additional water will be available to reduce shortages to other Basin water users. Therefore, 

when this option is included in a portfolio, the portion of the 720,000 af water savings in the 

Upper Basin will be used directly to reduce other Upper Basin users’ shortages, both within the 

Basin and in adjacent areas.

6.8 Water Yield Summary

As discussed previously, all of the agricultural water conservation measures have been 

conceptualized into two implementation approaches: 1) incentive-based programs and 2) water 

transfers. Because the conservation measures could produce different amounts of savings 

depending on the location in the Basin, implementation approach, and combination of 

conservation measures, the total quantities were estimated as an aggregate for each 

implementation approach rather than a summation of individual conservation measures. Up to 1 

mafy of potential savings by 2060 was considered for both approaches combined with potential 

of roughly 500,000 afy under each approach category. By comparison, the summation of 

potential water savings for each conservation measure totals 2.44 mafy when accounting for nonconsumptive use savings outside the Basin and ignoring return flow impacts, and is reduced to 

833,000 afy when only consumptive use savings are considered under each approach category. 

Table F10-2 summarizes the potential agricultural water conservation savings by measure and 

implementation method. 

TABLE F10-2 

Estimated Potential Water Savings at the Farm Scale for Each Agricultural Water Conservation Measure 

Water Conservation Measure

Reduction in 

Consumptive Use

(afy) 

Reduction in Total 

Diversion

(afy) 

Advanced Irrigation Scheduling 0 270,000

Deficit Irrigation 100,000 130,000

On-Farm Irrigation System Improvements 0 490,000

Conveyance System Efficiency Improvements 0 820,000

Controlled Environment Agriculture 13,000 13,000

Irrigated Lands Fallowing 720,000 720,000

TOTAL 833,000 2,443,000
Colorado River Basin

Water Supply and Demand Study

F10-14 December 2012

7.0 Timing of Option Availability

Because the agricultural water conservation options would be ramped over time, it was 

considered that the improvements to irrigation management, on-farm irrigation improvements, 

and changes in crop consumptive use could occur in as early as 10 years. Large infrastructure 

projects, including conveyance system efficiency improvements and controlled environment 

agriculture, were estimated to require at least 15 years before full implementation due to the 

planning, permitting, design, and construction needs. 

8.0 Costs

Costs for implementing agricultural water conservation measures would vary regionally and with 

different levels of conservation programs. Costs were estimated based on review of existing 

programs implementing such measures. Important sources of cost estimates for on-farm 

irrigation improvements and conveyance system improvements included Cooley et al. (2010); 

IID (2007), and engineering estimates using Natural Resource Conservation Service cost bases. 

All costs were translated into net annualized costs over the life of the improvement. When 

possible, capital cost amortization used the 2011 discount rate for water-related projects of 4.125 

percent. IID (2007) used a rate of 4 percent to amortize capital costs of irrigation system 

components over their expected useful lives. 

Based on the estimates reported by Cooley et al. (2010), the unit annual costs for improved 

irrigation scheduling and deficit irrigation were approximately $100 per afy and $43 per afy and 

the unit annual cost of on-farm irrigation efficiency improvements was $390 per afy. These 

estimates were based on total water savings, not reduction in consumptive use. 

Reductions in consumptive use through rotational or permanent fallowing were estimated based 

on existing fallowing programs and administration costs. The IID has recently offered $125 per 

afy to growers for fallowing fields to provide water for transfer and for Salton Sea flows (IID, 

2012). This price applies to the full reduction in applied water. The effective price per afy of 

reduced consumptive use would be substantially higher. A study by Pritchett et al. (2008) 

reported survey responses to the price to forgo 1 year of irrigation as ranging from about $200 to 

$750 per acre with a minimum of $50 and a maximum of $1,800 per acre. 

Costs for conveyance system efficiency improvements vary substantially depending on the 

characteristics of the existing delivery system. System improvement options developed for the 

IID Efficiency Conservation Plan (2007) ranged from $140 to $800 per afy of reduced diversion. 

Controlled environment agriculture costs vary by crop type, hydroponic or aquaponic system, 

and installation technique. Initial capital costs are more than 10 times higher than traditional 

agricultural operations, with construction costs of $3 to $7 per square foot reported for relatively 

large-scale greenhouses (USDA, 2003; Mississippi State University Extension Service, 2009). 

Based on an assumed 1.5 afy savings, unit annual costs are likely approaching $6,000 per af. 

This cost would be offset to some extent by improved crop yield, quality, and price, but these 

benefits are highly dependent on market conditions. Table F10-3 presents the estimated costs by 

measure
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-15

TABLE F10-3 

Estimated Potential Water Savings at the Farm Scale for Each Agricultural Water Conservation Measure 

Water Conservation Measure

Cost

(dollar per af) 

Advanced Irrigation Scheduling 100

Deficit Irrigation 43

On-farm Irrigation System Improvements 390

Conveyance System Efficiency Improvements 140-800

Controlled Environment Agriculture 6,000

Irrigated Lands Fallowing 125-700

In general, it is anticipated that agricultural conservation programs would be implemented in 

order from least costly to more costly and that these costs would vary somewhat by the program 

implemented and specific best management practices considered. It is assumed that 

“Conservation” is more focused on on-farm and delivery system improvements, whereas 

“Conservation with Transfer” is more focused on fallowing. Table F10-4 presents the estimated 

costs for about 1 mafy of savings when 200,000-afy increments are considered. Note that the 

initial level of “Conservation” is dominated by on-farm conservation, with other measures such 

as system conservation and fallowing being implemented in greater proportions in subsequent 

steps. Whereas, when transfers are considered, fallowing is the dominant measure. In both 

cases, costs increase with increasing yield requirements.

TABLE F10-4

Agricultural Conservation Annual Costs per af of Savings by Implementation Type

Savings 

(mafy) Conservation1 Conservation with Transfer2

Step 1 0.2 On-Farm $150 Fallowing $250

Step 2 0.4 $300 $400

Step 3 0.6 System $500 System $500

Step 4 0.8 $600 $600

Step 5 1.0 Fallowing $750 On-Farm $750

1 Begins with programs more heavily weighted toward On-Farm Measures (Deficit Irrigation, Advanced 

Irrigation Scheduling, On-Farm System Improvements) but includes some portions of System 

Improvements and Fallowing in subsequent steps. 

2 Begins with programs more heavily weighted toward Fallowing but includes some portions of System

Improvements and On-Farm in subsequent steps. 

9.0 Other Key Criteria 

In addition to yield, timing, and cost, the agricultural water conservation options were 

characterized against several other criteria. A summary of the findings for all criteria is shown in 

table F10-5. In general, these options are technically feasible, and there are examples in areas of 
Colorado River Basin

Water Supply and Demand Study

F10-16 December 2012

the Southwest and in other arid regions of the world. Controlled environment agriculture is 

unlikely to be economically feasible on a large scale under foreseeable circumstances. Irrigation 

management and efficiency improvement programs have been undertaken at district and state 

levels, but have not been demonstrated on basins of the scale of the Colorado River in North 

America. It is not anticipated that significant permitting issues or legal changes will be required 

to implement these options. However, these options will affect diversion patterns, return flow 

quantities and locations, and groundwater recharge. These changes could generate legal 

challenges. Policy concerns could arise with large-scale agricultural water transfers as public 

discourse on the maintenance of agricultural economies and effects to rural communities 

continues. Coupling agricultural conservation with a transfer mechanism can have varying 

degrees of political and legal complexities depending on the nature of the transfer. For example, 

an Upper Basin banking concept is explored in the Study that assumes water generated through 

agricultural conservation is transferred to a downstream conceptual water bank near Lake 

Powell. Transfers of this nature would have significant policy and legal challenges. The 

characterization ratings shown in table F10-5 assume all saved water in the Upper Basin states is 

made available to local water users within the priority system. 

All options have some implementation risk in that yields will fluctuate over time and programs 

will require continuous funding to maintain overall results. Controlled environment agriculture 

has additional risk from the very large capital requirements: at an average $5.43 per square foot 

(Mississippi State University, 2009), more than $2.6 billion would be required to construct the 

facilities for 11,000 net acres of production. Additional long-term risks would include 

maintaining sufficient revenue to pay the debt service and operations. For the other options, 

once savings are realized they can be maintained, resulting in long-term viability. 

The non-structural options were rated high with respect to operational flexibility because the 

programs can be stopped at any time without incurring significant debt service or resulting in 

stranded assets. However, structural (including irrigation infrastructure) options do not have 

high operational flexibility. Non-structural agricultural water conservation options do not 

require energy, but on-farm irrigation improvements generally will require energy for 

pressurizing sprinkler and drip systems or for pumping recycled tailwater. Greenhouses require 

pressurized irrigation and may require heating and cooling systems, depending on location and 

season of operation. Agricultural water quality issues primarily relate to fertilizers and pesticides 

in return flows to surface or groundwater. All of the options reduce return flows and therefore 

could have positive effects on water quality. All options would likely have generally positive or 

neutral impacts on hydropower and recreation. Impacts on other environmental factors are 

uncertain. In some cases, the lower diversions could be positive by leaving additional flow in 

streams; in other cases, reduced return flows could affect environmental resources such as 

riparian vegetation along canals and drains that have come to rely on the return flow. Structural 

options such as system conveyance improvements and controlled environment agriculture would 

have construction-related impacts.

All of the options would require some additional spending in local communities to implement, 

and would therefore support local economic activity. Only the reduced consumptive use options 

were rated low on socioeconomics because of their potential effect on agricultural communities 

under long-term fallowing and reduced crop production. It is possible that these effects can be 

mitigated by taking a Basin-wide rotational approach to this option such that individual 

communities do not experience the impacts in a sustained manner. 
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-17

10.0 Characterization Results 

A summary of the characterization findings are shown in table F10-5. The top portion of the 

table shows the estimated quantity of yield, earliest timing of implementation, and estimated 

cost. The bottom portion of the table shows the 17 criteria and associated ratings (“A” through 

“E”) and is color-scaled. In general, “C” is typically designated as mostly neutral (yellow); “A” 

is largely positive (green); and “E” is largely negative (red) or more difficult to accomplish. 

Refer to appendix F3 for specific criteria descriptions and rating scales.

11.0 References 

Altenhofen, J. 2012. Augmented Deficit Irrigation. Presentation at the CDWR-WD1 

Irrigationists Symposium, March 15, 2012. 

Bureau of Reclamation (Reclamation). 2011. Colorado River Basin Salinity Control Program, 

Federal Accomplishments Report for Fiscal Year 2011. Retrieved from 

http://www.usbr.gov/uc/progact/salinity/pdfs/FedAccompRep-2011.pdf. 

Colorado Agricultural Water Alliance. 2008. Meeting Colorado’s Future Water Supply Needs: 

Opportunities and Challenges Associated with Potential Agricultural Water 

Conservation Measures. September.

Cooley, H., J. Chrisian-Smith, P.H. Gleick, M.J. Cohen, M. Heberger. 2010. California’s Next 

Million Acre-Feet: Saving Water, Energy, and Money. Pacific Institute, Oakland, CA. 

Controlled Environment Agriculture Center. 2012. Total Areas in Major Greenhouse 

Production Countries. Summary by the Controlled Environment Agriculture Center at 

the University of Arizona. Retrieved July 25, 2012, from 

http://ag.arizona.edu/ceac/sites/ag.arizona.edu.ceac/files/WorldGreenhouseStats.pdf. 

Eching, S. 2002. Role of Technology in Irrigation Advisory Services: The CIMIS Experience. 

Irrigation Advisory Services and Participatory Extension in Irrigation Management 

Workshop, FAO – ICID. Montreal, Canada. 

English, M. and B. Nakamura. 1989. “Effects of Deficit Irrigation and Irrigation Frequency on 

Wheat Yields.” Journal of Irrigation and Drainage Engineering 115(2): 172-184. 

English, M. 1990. “Deficit Irrigation. I: Analytical Framework.” Journal of Irrigation and 

Drainage Engineering 116(3): 399-411. 

Gangwer, K. 2011. Challenges in Prospective Temporary Fallowing of Irrigated Agriculture in 

the Upper Colorado River Basin. December.

Geerts, S. and D. Raes. 2009. “Deficit Irrigation as an On-Farm Strategy to Maximize Crop 

Water Productivity in Dry Areas.” Agricultural Water Management, 96(9), 1275-1284. 

Goldhamer, D.A., M. Viveros, and M. Salinas. (2006). “Regulated deficit irrigation in almonds: 

effects of variations in applied water stress timing on yield and yield components.” 

Irrigation Science, 24: 101-114. 

Imperial Irrigation District (IID). 2012. 2012-2013 Land Fallowing Program. Retrieved July 

2012 from http://www.iid.com/index.aspx?page=190. 
Colorado River Basin

Water Supply and Demand Study

F10-18 December 2012

TABLE F10-5 

Summary Characterization Ratings for Agricultural Water Conservation Options
Appendix F10 — Option Characterization – 

Agricultural Water Conservation

December 2012 F10-19

Imperial Irrigation District (IID). 2007. Imperial Irrigation District Efficiency Conservation 

Definite Plan. 

Klamath Basin Rangeland Trust (KBRT). 2011. Klamath Basin Rangeland Trust Water 

Transactions Program. June 2011. 

Klamath Basin Rangeland Trust (KBRT). 2005. Klamath Basin Rangeland Trust, 2005: Year In 

Review. 

Mississippi State University Extension Service. 2009. Starting a Greenhouse Business. 

Publication 1957. 

Mpusia, P.T.O. 2006. “Comparison of Water Consumption Between Greenhouse and Outdoor 

Cultivation.” Thesis for Master of Science at the International Institute for GeoInformation Science and Earth Observation, Enschede, The Netherlands. 

National Agricultural Statistics Service. 2012. Acreage (June 2012). Released June 20, 2011. 

Retrieved from http://usda.mannlib.cornell.edu/usda/nass/Acre/2010s/2011/Acre-06-30-

2011.pdf. 

Pritchett, James, et al. 2008. Water Leasing: Opportunities and Challenges for Colorado’s 

South Platte Basin. WAEA Annual Meeting, June 26. Big Sky, Montana. 

Sandia National Labs. 2005. Systems Assessment of Water Savings Impact of Controlled 

Environment Agriculture Utilizing Wirelessly Networked Sense-Decide-ActCommunicate Systems. Report SAND2005-0759. 

Smith, S. 2011. “Strategies for Limited and Deficit Irrigation to Maximize On-Farm Profit 

Potential in Colorado’s South Platte Basin.” Ph.D. Dissertation, Dept of Civil and 

Environmental Engineering, Colorado State University, Fort Collins, Colorado. 

Tatum, D. and K. Hood. 2009. Starting a Greenhouse Business. Mississippi State University 

Extension Service, Publication 1957, last updated 19-Feb-2009. Retrieved from 

http://msucares.com/pubs/publications/p1957.htm. 

Trout, T., and W. Bausch. 2012. “Water Production Functions for Central Plains Crops.” 

Proceedings of the 24th Annual Central Plains Irrigation Conference. Colby, Kansas, 

February 21-22. 

Washington Department of Ecology (WDOE). 2005. Water Resources Program Guidance. 

Determining Irrigation Efficiency and Consumptive Use. GUID-1210. 

http://www.ecy.wa.gov/programs/WR/rules/images/pdf/guid1210.pdf

U.S. Department of Agriculture (USDA). 2007 Census of Agriculture. Retrieved July 2012 

from 

http://www.agcensus.usda.gov/Publications/2007/Full_Report/Volume_1,_Chapter_1_St

ate_Level/. 

U.S. Department of Agriculture (USDA). 2003. Greenhouse Tomatoes Change the Dynamics of 

the North American Fresh Tomato Industry. Economic Research Service. ERR-2. 
Appendix F11

Option Characterization –

Energy Sector Water Use Efficiency

December 2012 F11-1

Appendix F11 — Option Characterization –

Energy Sector Water Use Efficiency

1.0 Introduction

Options to improve the water use efficiency of the energy sector have been proposed to reduce 

the water demand in the Colorado River Basin (Basin). A number of energy sector water use 

efficiency options were submitted for consideration in the Colorado River Basin Water Supply 

and Demand Study (Study). The submittals are summarized in appendix F2 and the original 

submittals are available via links from the electronic version of appendix F2 on the compact disc 

that accompanies this report and the version of appendix F2 on the Study website at 

http://www.usbr.gov/lc/region/programs/crbstudy.html. 

Four options related to energy sector water use efficiency were received. The submitted options

were reviewed and organized into two groups according to the specific concept:

Conversion of Power Plants to Air Cooling

Water Use Efficiencies in the Oil and Gas Industry

Figure F11-1 shows the general location of major power plants in the Basin and the approximate 

magnitude of water use for cooling.

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Additional detail related to the 

options characterization is included in appendix F3.. Attachment A of appendix F3 contains 

more detailed descriptions of the ratings. Attachment B provides the methods used for 

completing the unit cost calculations. Attachment C presents the detailed characterization 

information and is available on the compact disc that accompanies this report and on the Study 

website.

2.0 Conversion of Power Plants to Air Cooling

This option group includes removing the evaporative cooling systems at the 15 largest power 

plants in the Basin (figure F11-1) and installing air cooling systems. 

Developing yield estimates for these options includes researching historical and estimated future 

use of water by power plants (Colorado River Water Consultants, 2008a). The 15 largest power 

plants in the Colorado River Basin region consume approximately 167,000 acre-feet per year 

(afy) of water. Assuming 95 percent of that amount could be saved by converting to air cooling, 

about 160,000 afy of yield is potentially available with this concept.
Colorado River Basin

Water Supply and Demand Study

F11-2 December 2012

FIGURE F11-1

Location of Major Power Plants within the Basin

When evaluating this option, the following were considered:

High cost of installing air-cooling systems 

Effect of air-cooling on plant power output during hot weather 

Effect of air cooling on plant efficiency

Applicability of air-cooling technology to the existing plant systems designed for watercooled service

Larger site footprint required for air-cooled system

The timing on conversion of cooling systems at power plants may depend to some degree on the 

remaining useful life of the existing systems. Some or even all of the 15 plants identified for 

conversion may be retired over the Study planning period. However, power needs are likely to 

still exist in the region, and new plants may replace the older plants. For the characterization of 

this option, it is assumed that a sense of urgency related to water imbalance results in agencies or 

the federal government moving forward with power plant conversions in conjunction with plant 

owners, regardless of the remaining useful life of the existing equipment. Feasibility studies to 
Appendix F11 — Option Characterization –

Energy Sector Water Use Efficiency

December 2012 F11-3

identify the estimated amount of power generation loss due to reductions in efficiency and plans 

for making up those losses are assumed to take up to 3 years. Revised air quality and noise 

permits are required for the alternate equipment, and it could take 2 or more years to acquire 

those permits. Detailed design and construction could take another 5 years, with a total 

timeframe of at least 10 years. 

Costs for energy water use efficiency concepts are based on literature research and previously 

completed conceptual designs. The costs for decommissioning a wet cooling system and 

construction of air-cooling systems, plus the increased cost of operation of the power plants,

were estimated in the Study of Long-Term Augmentation Options for the Water Supply of the 

Colorado River System (Colorado River Water Consultants, 2008). This study estimated the unit 

annual costs at approximately $1,300 per acre-foot (af) for plants of 2,000 megawatt (MW) and 

greater capacity and as much as $4,000 per af for plants smaller than 1,000 MW capacity. Three 

of the 15 largest plants in the region are larger than 2,000 MW; 4 plants are larger than 

1,000 MW and smaller than 2,000 MW; and the remainder are smaller than 1,000 MW

(Colorado River Water Consultants, 2008a). Therefore, the unit annual costs will vary at each 

facility, but the estimated weighted average is about $2,000 per af of water saved.

In addition to yield, timing, and cost, the conversions of power plants to air cooling was

characterized against several other criteria. A summary of the findings for all criteria is shown 

below. Key considerations related to technical feasibility, permitting, legal, and policy issues 

were largely covered in the descriptions above related to estimating option timing. The 

technology is proven and reliable, resulting in a high feasibility rating. In regard to 

implementation, there is likely to be pushback from the power industry because of increased 

costs and reductions in efficiency, as well as potential pushback from the public because of 

potential increased costs of energy to the greater community. The long-term viability is believed 

to be high because once the technology is installed and paid for, there is little risk of the system 

not achieving the reduced water demand. Based on the investment and infrastructure required, 

the operational flexibility is limited because the criterion penalizes options that have high debt 

service costs even when the option is put into an idle mode. Although the option conserves 

water use in the energy generation process, it is projected to reduce energy generation by 10 to 

15 percent. Applying the “fenceline” concept described in appendix F3 to the options 

characterization implies that the reduced generation is outside of the “fenceline”, resulting in a 

neutral score. When considering hydropower, water quality, recreation, and other environmental 

impacts, this concept could result in reduced diversion for these Upper Basin power plants and 

increased water in the river system. It is also unknown how this water would be used by others, 

which could result in a change in how downstream river reaches are operated. Because of these 

unknowns, neutral conditions were assumed for these criteria. Socioeconomic impacts are 

difficult to fully assess because jobs will be created with all of these options. There is also likely 

to be a combination of positive and adverse impacts in the regions in which the power plants are 

located. Without more-detailed assessments, neutral conditions were assumed for 

socioeconomics.

3.0 Water Use Efficiencies in the Oil and Gas Industry

This concept includes increased regulation on oil and gas exploration to protect water resources 

from contamination and use of treatment processes to make the byproduct water available as a 

new supply instead of disposing the water to evaporation lagoons or deep wells. These 
Colorado River Basin

Water Supply and Demand Study

F11-4 December 2012

byproduct waters typically have total dissolved solids concentrations of up to 15,000 milligrams

per liter (Colorado River Water Consultants, 2008b), and desalination of the water is required to 

render it suitable for use as a new supply. The energy required for desalination, along with the 

energy required to transport the water to central locations of treatment and use, leads to total 

energy requirements of 4,700 kilowatt hours per af. This concept also includes maximizing 

efficiency of use of water at oil and gas refineries. Although described here for completeness, 

the treatment and use of the natural gas byproduct water is included in the local supply category

and is not characterized here. Also, increased reuse of industrial type waters is covered in the 

industrial reuse category and not characterized here.

4.0 Results

A summary of the characterization findings are shown in table F11-1. The top portion of the 

table shows the estimated quantity of yield, earliest timing of implementation, and estimated 

cost. The bottom portion of the table shows the 17 criteria and associated ratings (“A” through 

“E”) and is color-scaled. In general, “C” is typically designated as mostly neutral (yellow); “A”

is largely positive (greed); and “E” is largely negative (red). Refer to appendix F2 for specific 

criteria descriptions and rating scales.

5.0 References

Colorado River Water Consultants. 2008a. Technical Evaluation of Options for Long-Term 

Augmentation of the Colorado River System, Reduction of Power Plant Consumptive 

Water Usage for Colorado River Augmentation.

Colorado River Water Consultants. 2008b. Technical Evaluation of Options for Long-Term 

Augmentation of the Colorado River System, Coal Bed Methane-Produced Water.
Appendix F11 — Option Characterization –

Energy Sector Water Use Efficiency

December 2012 F11-5

TABLE F10-1

Summary Characterization Ratings for Energy Sector Water Use Efficiency Options K=thousand

Appendix F12

Option Characterization – System Operations

December 2012 F12-1

Appendix F12 — Option Characterization –

System Operations

1.0 Introduction

Modified system operations have been proposed to decrease demand, reduce evaporation losses,

and improve efficiency within the Colorado River Basin (Basin). A number of system 

operations options were submitted for consideration in the Colorado River Basin Water Supply 

and Demand Study (Study). The submittals are summarized in appendix F2 and the original 

submittals are available via links from the electronic version of appendix F2 on the compact disc 

that accompanies this report and the version of appendix F2 on the Study website 

at http://www.usbr.gov/lc/region/programs/crbstudy.html.

Twenty four options related to System operations were received. These options consist of 

essentially three major overarching concepts:

Evaporation Control Covers

New Water Storage

Modified Operation

These three concepts can be further grouped into three representative options for evaporation 

control covers, three representative options for new water storage and four representative options 

for Modify Operations. When potential yield of a representative option exceeds 200 kafy and the 

option is scalable, the representative option was characterized in progressive 200 kafy “steps”. 

Figure F12-1 shows the general locations of options.

For the system operations category of options, only the options in the Evaporation Control 

Covers and New Water Storage underwent a characterization with ratings assigned to each 

criterion. Due to their technical and legal complexity, the options that comprise the Modify 

Operations group were not assigned ratings. However, available information on relevant criteria 

is discussed below. 

This appendix summarizes the types of options received, the assumptions made and methods 

used to characterize the options, and the characterization results. Detailed description of the 

characterization criteria, approach, and rating guidance is provided in appendix F3.

2.0 Evaporation Control Covers

This group of options includes physical and chemical methods to reduce evaporation from the 

major canals and reservoirs. Physical covers would incorporate solar photovoltaic panels to 

simultaneously reduce evaporation and generate electricity. Concepts involving chemical covers 

include the introduction of a chemical to the water surface of large reservoirs to reduce the 

evaporation rates of the reservoirs. 

Based on these distinct concepts, three representative options were developed:

Solar Panel Canal Covers

Solar Panel Reservoir Covers

Chemical Type Covers
Colorado River Basin

Water Supply and Demand Study

F12-2 December 2012

FIGURE F12-1

General Locations of System operations Options within the Basin

2.1 Solar Panel Canal Covers

Solar panels covering the water surface of open canals were evaluated by estimating the water 

surface area and potential for reduced evaporation rates. The total water surface area of the 

largest canals (Colorado River Aqueduct, Central Arizona Project, and All American Canal) was 

estimated by reviewing aerial mapping. Next, evaporation rates from the canals were researched. 

Last, it was assumed that covering the canals as described in the options would reduce the 

current evaporation rate by 50 percent. However, pilot investigations would be needed to 

confirm and refine this assumed reduction as appropriate. The estimated potential water savings 

for installing solar panel covers over the major canals is approximately 18,000 acre-feet per year 

(afy).

The yield of this concept is highly dependent on the actual reduction in evaporation rates, and the 

overall costs are highly dependent on recovering some costs by selling energy. To better 

understand the potential of this option, a 3-year feasibility study, including a pilot program,

should be considered. If deemed feasible and the concept was aggressively pursued, 2 years of 

permitting followed by 5 years of construction is plausible, totaling 10 years. 

SPG Solar (2007) performed a pilot study and published the results showing that 3 acres of 

floatovoltaic (floating photovoltaic) coverage has an estimated capital cost of $5 million and 

generates about 1 megawatt of power. Assuming the photovoltaic panels have a 15-year life and 
Appendix F12 — Option

Characterization – System Operations

December 2012 F12-3

are amortized at 4.125 percent, the annual cost of the $5 million installation is about $450,000. 

Assuming the power generated can be sold at $0.05 per kilowatt hour, the power generation is 

worth $135,000. Assuming 5 feet per year evaporation reduction, a very rough estimate of costs 

is $20,000 per acre-foot (af). Because the cost of this option is approximately 10 times more 

expensive than many other options, additional study was not performed to further refine the 

costs. However, renewable energy credits or higher energy prices could lower the cost per af. 

Conversely, additional costs for security to avoid theft of the photovoltaic panels would add 

costs to this concept.

In addition to yield, timing, and cost, the evaporation reduction options were characterized 

against several other criteria. Key considerations related to technical feasibility, permitting, 

legal, and policy were largely covered in the descriptions above related to estimating option 

timing. Permitting is expected to be substantially challenging for physical covers. Operational 

flexibility of this option is relatively low because the concept cannot be idled in particular years 

due to infrastructure and operational limits. Physical covers will pose additional maintenance 

challenges compared to open canals. The solar panel covers actually generate energy. In regard 

to hydropower, all concepts that reduce evaporation can later increase hydropower production. 

In general, those options that reduce evaporation most significantly have the most positive 

impact. Moderate improvements to water quality are anticipated for all evaporation reduction 

options because of higher canal flows that reduce salinity concentrations. Recreation may be 

influenced by all of the system evaporation reduction options, either through limiting 

recreational access or through unknown body contact restrictions. Conversely, reducing 

evaporation will likely result in a small increase in lake levels. Environmental impacts are 

highly variable between concepts, depending on potential changing operations or impacts related 

to covering water bodies. Socioeconomic impacts are difficult to fully assess because jobs will 

be created with all of these options, but there is also likely to be a combination of positive and 

negative impacts when considering more than just job creation. Without more-detailed 

assessments, neutral conditions were assumed for socioeconomics.

2.2 Solar Panel Reservoir Covers

Floating solar panel covers were also proposed to cover portions of the water surface of 

reservoirs to reduce evaporation. It was assumed that about 10 percent of the reservoir surface 

area in major reservoirs (Lakes Powell, Mead, and Havasu) could be covered, resulting in up to 

200,000 afy of reduced evaporation using similar assumptions as those for canals.

Compared to the canal covers, an additional 5 years is anticipated to be required for the 

“floatovoltaic” concepts to address potential issues with covering the lakes in the severe 

Southwest environment and to minimize effects to recreation. This would bring the total time to 

implement to approximately 17 years. Cost estimates were developed as described for the canal 

covers, resulting in rough estimates of $15,000 per af. Reducing evaporation will likely increase 

lake levels and may positively influence shoreline recreational access. Other key criteria were 

similar to the canal covers option.

2.3 Chemical Type Covers

This concept includes introducing chemicals to large reservoirs (Lakes Havasu, Mead, and 

Powell) that reduce the evaporation rates of the reservoirs.
Colorado River Basin

Water Supply and Demand Study

F12-4 December 2012

For this concept, it was assumed that evaporation-reducing chemicals would be added to Lakes

Mead and Powell. The maximum reduction in evaporation is assumed to be 50 percent. 

However, pilot investigations would be needed to confirm and refine this assumed reduction as 

appropriate. Assuming the average evaporation from Mead and Powell is around 1.7 million 

acre-feet per year (mafy), this would result in about 0.85 mafy of evaporation savings. Because 

of the large areas being considered for this option and the need to fully evaluate feasibility of the 

option, it would be implemented in several phases. Characterization of this option was performed 

as increments of 200 thousand acre-feet (kaf) in order to capture issues of scale and other 

complexities of large-scale programs.

The yield of this concept is highly dependent on the actual reduction in evaporation rates and 

successful completion of the environmental review process. Because use of chemical covers to 

reduce evaporation is not common practice and the feasibility of this option has not been 

evaluated in the extreme environment and weather conditions of Lake Mead and Lake Powell, 

feasibility studies followed by pilot programs on smaller water bodies would be expected before 

attempted on any large scale. Also, extensive permitting would likely be required to show (with 

confidence) that adding the chemical to the water does not have negative impacts on water 

quality, public health, or the ecosystem. It was assumed that the studies and a small pilot-scale 

test could take place within 5 years. Next, a larger-scale pilot test of an additional 5 years may 

be required, followed by permitting and additional testing. Therefore, it could take 15 years 

before full-scale implementation. 

This concept includes costs for airplanes, fuel, pilots, aircraft maintenance, and chemicals. 

Assuming chemical application every 10 days and two planes for chemical application, annual 

operation and maintenance is on the order of $38 million per year. Amortizing the cost of 

purchasing or leasing the airplanes ($3.8 million) and estimating the annual costs of the other 

cost items results in a rough estimated unit cost of about $100 per af. However, costs for 

monitoring to show that the chemicals do not negatively affect the aquatic ecosystem is not 

included.

In addition to yield, timing, and cost, the evaporation-reduction options were characterized 

against several other criteria. Key considerations related to technical feasibility, permitting, 

legal, and policy were largely covered in the descriptions above related to estimating option 

timing. Widespread application of chemical covers does not have a historical precedent to 

establish technical feasibility. Permitting is expected to be substantially challenging for 

chemical covers as well as for physical covers. Operational flexibility is related to the ability to 

idle the concept in wet years without negative consequences. Chemical covers therefore are 

shown as more operationally flexible than physical covers. Energy needs are relatively low for 

the chemical cover concepts. In regard to hydropower, all concepts that reduce evaporation in 

reservoirs can later increase hydropower production. In general, those options that reduce 

evaporation the most have the most positive impact. Other key criteria were characterized very 

similarly to the canal and reservoir cover options.

3.0 New Water Storage 

This group of options involves the construction or expansion of reservoir projects in order to 

increase the amount of storage available on the system. There are two representative options in 

this group:
Appendix F12 — Option

Characterization – System Operations

December 2012 F12-5

New Water Storage

Improved Groundwater Management

3.1 Pumped Storage – Central Colorado Project

The Central Colorado Project (CCP) proposes a high-altitude, off-river, pumped-storage facility 

concept. Union Park Reservoir would be located near the Continental Divide in Gunnison 

National Forest with a storage capacity of 1.2 maf. The reservoir would be capable of delivering 

water to the South Platte, Arkansas, and Rio Grande basins. It would be able to tie into the 

existing Fryingpan Arkansas Upper Colorado River Collection System and serve the 

communities in the central Front Range and Colorado Springs. The reservoir would be filled by 

pumping excess water during spring snowmelt months from existing Blue Mesa and Taylor Park 

reservoirs (Miller, 2007). 

Storing 1.2 maf in the proposed high-altitude Union Park Reservoir instead of Lake Powell 

would result in some additional yield due to reduced losses from evaporation. Based on existing 

evaporation rates at each location, approximately 20,000 afy could be saved under ideal 

conditions.

All aspects of the proposed CCP are currently feasible from a technical standpoint. Overall 

feasibility investigation of the concept has already begun and could be completed within 3 years. 

However, construction of a new dam and modified flows in the upper reaches of the Basin would 

require significant permitting activities and preparation of an EIS. This proposed project has 

faced significant opposition for more than 30 years from Gunnison River Basin and other 

Colorado water users. The permitting process is expected to take a significant amount of time 

due to the strong and organized coalition of project opponents. Allowing for 7 years to 

complete the permitting process and 5 years to construct the facilities, the CCP would take 

approximately 15 years to implement.

According to the information provided in the option submittal, construction of the Union Park 

Reservoir would cost approximately $400 million. For the purposes of the Study, it was 

assumed that other facilities considered in the plan, including pipelines and pump stations 

between the new and existing reservoirs would cost an additional $200 million to construct. It 

was also assumed that the cost of operations would be significantly reduced by the revenue 

generated from energy production. Based on these assumptions and considering a yield of 

20,000 afy, the unit cost of conserved water is approximately $2,250 per af.

Additional key criteria for the pumped storage CCP option include permitting, operational 

flexibility, and energy needs. No recent precedent exists for successfully permitting such a 

facility in the proposed region in the recent past, and the project has had significant organized 

opposition for more than 30 years. Although there are no technical feasibility issues with 

operational flexibility, the debt service for the capital costs would still be required in all years. 

This is problematic because a portion of the debt is proposed to be serviced by power-generating 

revenues, and power generation may be limited during high-flow years.

3.2 Reservoirs to Capture Unused Releases

This option concept is based on the recently constructed Warren H. Brock Reservoir System 

(Brock Reservoir). Between 2008 and 2010, Reclamation constructed an 8,000-af storage 

reservoir near Drop 2 of the All-American Canal in Southern California. The new 
Colorado River Basin

Water Supply and Demand Study

F12-6 December 2012

reservoir stores Colorado River water that has been released from Parker Dam to meet 

downstream water orders but cannot be delivered for various reasons, such as changed weather 

conditions, high runoff into the river, or a number of other factors. In recent years, previous to 

the operation of Brock Reservoir, this water typically was not put to beneficial use within the 

United States due to the lack of sufficient storage capacity downstream of Parker Dam. Factors 

such as evaporation, transpiration by vegetation, channel storage, tributary flows, infiltration, 

weather conditions, unscheduled pumping from the river, variations in water user demands, and 

variations in return flows can significantly affect scheduled water deliveries and river regulation, 

thereby causing water to otherwise go unused in the United States and flow into the United 

Mexican States (Mexico). Although no specific sites were identified in the option submittal, it 

was proposed that additional reservoirs would be built to further improve the efficiency of the 

system.

Because specific locations have not been identified, the additional volume of water made 

available cannot be accurately estimated. Extensive evaluations would be required to calculate 

the potential cost and yield of additional reservoirs similar to the Brock Reservoir.

Based on the cost of the recently completed Brock Reservoir, this option is estimated to cost 

$500 per af. 

Additional key criteria for this option include technical feasibility, timing, permitting, long-term 

viability, and operational flexibility. The design and construction of an additional storage 

reservoir is technically feasible – any such project would follow industry standards that require 

no new technologies. Identification of permitting issues, on the other hand, is challenging 

because an exact project has not been identified. Any new reservoir proposed by a federal 

agency would require compliance with the National Environmental Policy Act and Endangered 

Species Act; therefore this option scored low on timing and permitting. This option also scored 

low on long-term viability and operational flexibility because of the uncertainty in yield and the 

high capital costs that would be incurred even if no flows were captured in a given year and the 

system were idle. This concept was assumed to be neutral on recreation, socioeconomics, 

energy, and water quality. 

3.3 Improved Groundwater Management

Current groundwater management practices within the Basin vary widely from state to state. 

This option would establish Basin-wide groundwater management practices that would control 

overdraft of groundwater resources to promote long-term sustainability; prevent groundwater 

pumping from depleting rivers, streams, springs, and other groundwater-dependent resources; 

and allow for underground storage of water supplies and strategic recharge of groundwater 

where possible.

Although careful management of groundwater is important for the overall benefit of the Basin, 

this option would not create any new supply and could reduce shorter-term available supply by 

decreasing dependence on unsustainable groundwater overdraft. 

The time required to change current practices would vary by region. Groundwater curtailment 

plans typically require complementary plans for alternative water supply development or water 

conservation, and typically both. The Study assumed at least 5 years of feasibility analysis to 

develop such complementary plans. Many places in the Basin that have experienced significant 

groundwater level declines have local legal and permitting requirements in place to manage the 
Appendix F12 — Option

Characterization – System Operations

December 2012 F12-7

limited groundwater supply. The submitted concept involves similar, but possibly moreaggressive management of the groundwater basins or extension of this management to all 

groundwater basins. Consequently, the Study assumed 3 years for permitting. Given at least 5 

years for feasibility, 3 years for permitting, and assuming 2 additional years for implementation, 

benefits would be seen in at least 10 years. 

Without specific details and project locations, the cost is difficult to estimate and would also 

likely vary by region. However, groundwater is typically an inexpensive supply source. The 

average cost of replacing low-cost groundwater with a higher-cost alternative was estimated at 

$2,000 per af.

There are trends towards curtailment of non-sustainable groundwater pumping; however, if this 

were to result in significantly increased costs or hardship, policy challenges would be 

anticipated. For these reasons, public acceptance is unknown. Consequently, this option scores 

low on the policy criterion. This option does score high on long-term viability, however, 

because it is envisioned that once an alternative supply becomes available, that supply will be 

used. Without additional details and study, this concept is considered fairly neutral for most 

other characterization criteria.

4.0 Modify Operations of Existing Reservoirs

This group of options includes changing operations to achieve a variety of improved efficiency 

goals and consists of a broad spectrum of individual options. The options predominantly involve 

modifying reservoir operations (reservoir operations), but also include groundwater management 

and storage. 

From these concepts, six options were developed:

Reduce Reservoir Evaporation

Prioritize Lake Mead Storage

Maximize Hydropower Generation

Operating for Environmental Purposes

4.1 Reduce Reservoir Evaporation

Research shows evaporation at Lake Powell is 50 inches per year, 50 inches per year (Colorado 

River Consultants, 2008). Similarly, evaporation at Lake Mead is estimated to average 

approximately 80 inches per year (USGS, 2006). Therefore, it may be possible to preferentially 

store water in Lake Powell to some degree rather than Lake Mead and reduce evaporation. The 

reservoirs have different surface area-to-storage characteristics, and there are numerous other 

operational objectives that must also be considered. Based on these differences, it is not possible 

to perform simple calculations to estimate potential benefits of evaporation savings associated 

with revised operations. 

Using the evaporation equations from the Colorado River Simulation System model for Lakes 

Powell and Mead, annual combined evaporation loss was computed for three total storage 

volumes – 16 million acre-feet (maf), 25 maf, and 33 maf (roughly 33, 50, and 66 percent of 

combined capacity). The distribution of those volumes was varied from (1) store as much as 

possible in Lake Mead to (2) store as much as possible in Lake Powell. As more water is stored 

in Lake Mead, the total evaporation increases. As more water is stored in Lake Powell, total 
Colorado River Basin

Water Supply and Demand Study

F12-8 December 2012

evaporation is reduced. The difference between the two extremes ranges from 175,000 afy to 

about 300,000 afy, depending on the total volume distributed between the two reservoirs. This, 

however, does not represent the range of potential savings from reoperation. As a gross 

estimation, in accordance with the Record of Decision for Colorado River Interim Guidelines for 

Lower Basin Shortages and Coordinated Operations for Lake Powell and Lake Mead (2007 

Interim Guidelines [U.S. Department of the Interior (DOI), 2007]), total storage tends to be 

roughly balanced between the two reservoirs presently. As a result, reoperation from the current 

distribution to the “optimal for evaporation reduction” distribution could yield at most 100 to 

200,000 afy depending on the total reservoir volume. Last, it is highly impractical that Lake 

Mead would be operated with as little water in storage as possible in favor of preferentially 

storing all water in Lake Powell. For perspective, it is likely that, at minimum, enough storage to 

generate power would be maintained. Reoperation from the current roughly 50/50 distribution to 

preferential storage in Lake Powell while maintaining the power pool at Lake Mead might yield 

10,000 to 100,000 afy of reduced evaporation, but again, this is highly dependent upon the total 

volume at any given time.

Other studies have estimated between zero and 290,000 afy of savings may be possible 

depending on assumed operating scenarios and future hydrology conditions (Colorado River 

Water Consultants, 2008). Analysis completed as part of this study, based on area-capacity 

curves of the two reservoirs, suggests that the potential for water savings may range from less 

than 100,000 afy to almost 300,000 afy depending on how much “preferential” storage is 

permitted in Lake Powell.

The modification of Lakes Powell and Mead operations to reduce evaporation losses has 

significant legal and political implications. Any operational modifications could not occur until 

after 2026 when the 2007 Interim Guidelines expire. Furthermore, re-operating either reservoir 

solely to reduce evaporative losses is not consistent with either facility’s authorized purposes.

This concept requires reoperation of the river system between Lake Powell and Lake Mead, but 

no new facilities. However, there would likely be significant costs associated with the changes

in timing of water deliveries, hydropower generation, and ecological and recreational impacts. 

Due to their complexity, these costs were not estimated for the Study. 

In addition to yield, timing, and cost, the evaporation reduction options were characterized 

against several other criteria. Key considerations related to technical feasibility, permitting, 

legal, and policy were considered in option timing. Hydropower generation, and the recipients 

of that generation, may be affected depending on how the operations are implemented. 

4.2 Prioritize Lake Mead Storage

This group of options would designate Lake Mead as the primary water storage and distribution 

facility for the Upper and Lower basins. These concepts varied in their vision of Lake Powell. 

One option envisioned Lake Powell being maintained at the elevation level of 3,490 feet above 

mean sea level, allowing for continued power production, and otherwise being used for seasonal 

flow variations, flood control, and sediment distribution purposes. Another option considered 

the transfer of Lake Powell storage to groundwater aquifers, a sediment management program, 

and entertained the possibility of removing Lake Powell altogether. The concepts associated with

decommissioning Glen Canyon Dam are outside the scope of the Study. 
Appendix F12 — Option 

Characterization – System Operations 

December 2012 F12-9 

The prioritizing Lake Mead storage concept has extreme environmental, recreational, and policy 

issues. There would likely be significant public opposition to lowering Lake Powell resulting 

from impacts on legal obligations and policy objectives, because Lake Powell provides the 

mechanism for the Upper Basin to satisfy its compact obligations. Additionally, drawing down 

Lake Powell would result in reduced yield to the system. Losses due to evaporation would 

increase if additional water currently stored in Lake Powell were released to Lake Mead. The 

option to remove Lake Powell altogether would have significant negative impacts to the system 

because system storage would be dramatically reduced. 

Changing the operations procedures at either Lake Mead or Lake Powell would not require any 

new facilities and is currently technically feasible. Time would be needed to establish new 

operational procedures and agreements among affected agencies and Reclamation, and to 

complete environmental permitting requirements. Assuming this process could be completed in 

5 years and the revised operations completed in 2 years, modifications to operations that 

prioritize Lake Mead storage could take place in as few as 7 years. However, modifying the 

2007 Interim Guidelines (DOI, 2007) is outside the scope of the Study, so this option was 

considered to be available in 2026, at the earliest. 

Revisions to operations could affect other operating objectives. Lowering Lake Powell would 

have negative impacts on recreation on the lake, but could have positive impacts on recreation on 

the river through the Grand Canyon and on Lake Mead. This option was also characterized 

negatively with regard to operational flexibility and energy needs. Positive impacts of this group 

of options include potential impacts to river flows downstream of Glen Canyon Dam. Because 

of a more-natural flow regime, environmental conditions for that portion of the river could be 

potentially improved. 

4.3 Maximize Hydropower Generation

Because of seasonal flow variations and year-to-year changes in hydrologic conditions, the 

hydropower generating reservoirs in the Basin often do not operate at optimal capacity. This 

concept proposes improving power generating efficiency in one of two ways. The first option 

would modify reservoir operations to reduce bypass flows, particularly at the Aspinall Unit, 

Crystal, Flaming Gorge, and Fontenelle reservoirs. Such operational changes could include a 

combination of changes to up- or down-ramp rates, timing of releases, and reservoir elevations. 

The second option would change reservoir operations to provide minimum elevations, ensuring 

that ability to generate power is consistently maintained. 

Because the purpose of this concept is to maximize power-generating capacity, it has minimal 

effects on yield. Moving the location of storage to different reservoirs to provide the needed 

flexibility may result in negligible changes to evaporation losses. For the purposes of the Study, 

these options were considered to result in no new yield.

No new facilities would be needed, but time to negotiate and develop modified operation plans 

would be required. For the purposes of the Study, an implementation period of up to 10 years 

was assumed, including 3 years for feasibility, 3 years for permitting, and 4 years for 

implementation. 

Because this concept does not create any new water supply and is based on modified operations 

the cost per af of yield has not been developed. Although it would not produce any additional 
Colorado River Basin

Water Supply and Demand Study

F12-10 December 2012

supply, hydropower re-operation has the principal benefit of increasing power generation within 

the system. Otherwise, this concept is fairly neutral for most of the characterization criteria.

4.4 Operating for Environmental Purposes

This group of options involves modifying reservoir operations in order to provide a higher 

degree of river ecosystem and recreational benefits. These benefits would be generated by 

maintaining or restoring river flows, with potential modifications to the quantity or timing of 

flows, for example, on an hourly or daily basis. This concept involves the continued and adaptive 

operation of reservoirs in the Basin. Where benefits are provided within the current flow 

regimes, these options involve the development of legal and policy mechanisms that protect 

those regimes. 

This concept would have minimal effects on yield, assuming no changes to operations on an 

annual basis. Changing flow regimes may result in negligible changes to evaporation losses. 

For the purposes of the Study, these options were also considered to result in no new yield. 

This concept would require the institution of policies or formation of adaptive management work 

groups. National Environmental Policy Act and Endangered Species Act compliance would be 

required. Because of the broad nature of this group of options, the time required to formulate 

these mechanisms would vary. Formulation of an adaptive management work group could take 

2 or more years, whereas environmental compliance might take 3 years resulting in benefits in 5 

to 7 years. However, modifying the 2007 Interim Guidelines (DOI, 2007) is outside the scope of 

the Study, so this option was considered to be available in 2026, at the earliest. 

This concept scores positively for recreation, environment, and wildlife. However, it scores 

negatively for energy and the potential risk of lack of long-term commitment to revised 

operations.

5.0 Characterization Results

A summary of the characterization findings are shown in table F12-1. The top portion of the 

table shows the estimated quantity of yield, earliest timing of implementation, and estimated 

cost. The bottom portion of the table shows the 17 criteria and associated ratings (“A” through 

“E”) and is color-scaled. In general, “C” is typically designated as mostly neutral; “A” is largely 

positive; and “E” is largely negative. Refer to Appendix F3 for specific criteria descriptions and 

rating scales.

Notes providing detailed justification for each option criteria rating are available in electronic 

form on the accompanying compact disc and on Reclamation’s website at 

http://www.usbr.gov/lc/region/programs/crbstudy.html.
Appendix F12 — Option

Characterization – System Operations

December 2012 F12-11

TABLE F12-1 

Summary Characterization Ratings for System Operations Options
Colorado River Basin

Water Supply and Demand Study

F12-12 December 2012

6.0 References

Colorado River Water Consultants. 2008. Study of Long-Term Augmentation Options for 

the Water Supply of the Colorado River System.

SPG Soloar. 2007. Far Niente Winery Case Study.

Miller, D. 2007. Central Colorado Project Western Renewable Energy & Water 

Productivity Multiplier. Natural Energy Resources Company.

U.S. Department of the Interior (DOI). 2007. Record of Decision for Lower Basin Shortages 

and the Coordinated Operations for Lake Powell and Lake Mead. 

USGS. 2006. Evaporation from Lake Mead, Arizona and Nevada, 1997-99. U.S. Geological 

Survey Scientific Investigations Report 2006-5252.
Appendix F13

Options Submitted by the Ten Tribes Partnership 

and the Inter Tribal Council of Arizona

December 2012 F13-1

Appendix F13 — Options Submitted by the 

Ten Tribes Partnership and the Inter Tribal 

Council of Arizona

Options pertaining to water development and use were submitted by tribes for consideration in 

the Colorado River Basin Water Supply and Demand Study (Study). In particular, this appendix 

includes the original options that were submitted by the Ten Tribes Partnership and the Inter 

Tribal Council of Arizona. See attachment A for the original option submitted by the Ten Tribes 

Partnership and see attachment B for the original option submitted by the Tribal Council of 

Arizona.

Appendix F13

Attachment A 

Option Submitted by the

Ten Tribes Partnership

December 2012 F13-A-1

Attachment A — Option Submitted by the 

Ten Tribes Partnership

TEN TRIBES PARTNERSHIP’S PROPOSED OPTION: 

VOLUNTARY TRIBAL WATER TRANSERS

In past work with the Bureau of Reclamation (“BOR”), the Ten Tribes Partnership 

has emphasized the BOR’s trust responsibility to protect and to develop for the benefit of 

member Tribes the water rights reserved for the benefit of the Tribes under federal law 

(“reserved rights”). See, e.g. Letter from Jessica R. Aberly to David J. Hayes, Deputy

Secretary of the Interior (Jan. 8, 2001). The Ten Tribes Partnership reiterates BOR’s trust 

responsibility here and asserts that the BOR, in carrying out a study of the supply and 

demand of the Colorado River Basin water (“Basin Study”), is legally required to ensure that 

the reserved rights of each of the member Tribes are recognized and protected in the BOR’s

representation of the current use and future imbalances in the water supply and demand in the

Basin.

The Ten Tribes Partnership asserts here that the Basin Study must recognize that the 

member Tribes are the rightful owners of their full water entitlements (both the developed and 

undeveloped portions, and both the quantified and unquantified entitlements) to yield greater 

predictability to models of future imbalances in the Basin. At the February 8, 2012 meeting 

between the Ten Tribes Partnership and the BOR in Parker, Arizona, BOR representatives stated 

that the modeling work for options to resolve future supply and demand imbalances would 

assume that any undeveloped portions of reserved rights are not available to resolve any future 

imbalances in the Basin. The member Tribes appreciate this BOR action to ensure that the 

future options modeling work does not contemplate the use of undeveloped tribal water

entitlements without the consent of the appropriate Tribe. The member Tribes look forward to 

working individually with the BOR to ensure that the BOR model properly represents and 

protects the full water entitlement of each member Tribe. The Ten Tribes Partnership asserts 

that the BOR modeling work and storylines for the water supply assessment (identifying the 

supply and demand imbalances) must also reflect the extent to which the demands of other water 

users cannot be met without utilizing any undeveloped portions of tribal water entitlements. We 

would like to schedule a meeting between BOR and the Ten Tribes Partnership technical group 

as soon as possible to determine the most feasible way to accomplish such analysis.

Assuming that BOR has adequately modeled or otherwise accounted for full tribal 

ownership of each water entitlement and has identified the potential use of any undeveloped 

tribal water by others, the Ten Tribes Partnership proposes that BOR assess how voluntary 

transfers of tribal water might be used to assist in meeting future imbalances. This 
Colorado River Basin

Water Supply and Demand Study

F13-A-2 December 2012

assessment should not be constrained by any particular interpretation of existing law and 

policy in the Colorado River Basin.

Each member Tribe has the sovereign right and authority to regulate the use of its water 

resources, and currently each Tribe has committed a portion of its water rights to uses within its 

Reservation boundaries. Each Tribe will have a different policy and different issues with 

respect to the various options for use of its waters. There are a number of voluntary tribal 

transfers which one or more of the Tribes are exploring, or may wish to explore, to utilize their

water entitlements for the ultimate benefit of their members. The voluntary tribal transfers will

likely include, but are not limited to, water banking, water marketing, leasing and forbearance 

agreements. These transfers could be to any existing user of Colorado River water without

regard to geographic limits. The analysis should include the extent to which each Tribe’s 

ability to use its water rights on any of its lands without regard to State boundaries would assist 

in meeting demands in the Basin as a whole.

These proposed tribal water transfers are largely conceptual at this time. However, 

States and other entities have implemented a variety of programs to improve the efficiency of 

water use in ways that previously would have been considered unacceptable under the Law of

the River. There are also successful water transfer arrangements in place in the Colorado River 

Basin involving tribal water and non-Indian communities. For example, the litigation between 

the United States and the Quechan Indian Tribe, on the one hand, and the states of California 

and Arizona and the Metropolitan Water District (MWD), et al. on the other, illuminated the

fact that the Tribe was entitled to water beyond its current needs while at the same time

providing water to agencies, such as MWD, which was in dire need of water given drought

conditions and increasing water needs. Thus, as part of the overall settlement of Quechan’s 

entitlement, an agreement was achieved between Quechan and MWD to allow MWD to receive 

the benefit of unutilized water allocation in any given year. In a unique action, the United States 

concurred in this agreement which allows tribal water to be exchanged and utilized by nontribal 

users for a cash payment. The Agreement, approved by the United States Supreme Court in the

2006 decree, provides essentially that the Tribe may, at its sole option, choose to forebear (i.e.,

not use) its allocation and assign that allocation to MWD for an “add on” to MWD’s allocation. 

This option is solely at the Tribe’s discretion and may be utilized on a year-to-year basis. The

initial quantity of water available under the Agreement is 13,000 acre feet a year with an 

additional 7,000 acre feet available in 2035.

Also, the Jicarilla Apache Nation has settlement water that it leases to a number of 

different entities for off reservation use subject to the approval authority of the Secretary of the 

Interior, and the Nation exports for depletion out of the Colorado River Basin 6,500 acre feet for 

use in the Rio Grande Basin. In addition to leasing settlement water, the Nation, through its 

Water Administration Office, permits bulk sale of decreed water. This water is available to 

users in and outside of the Colorado River Basin. Using this approach eliminates the necessity

of having to obtain Secretary of the Interior approval, which is required for leases of water for 
Colorado River Basin

Water Supply and Demand Study

December 2012 F13-A-3

off reservation use, because no interest in the Nation’s water rights is being conveyed. This

approach increases the efficient use of water by those in need. This procedure will continue to 

be used by the Nation in the future.

These examples demonstrate that voluntary tribal water transfers can be used to meet the 

needs of Colorado River Basin users as well as out of basin users. Voluntary tribal water 

transfers could occur to the benefit of existing Colorado River Basin users if the proper 

agreements are put into place. The Ten Tribes Partnership is now asking BOR to help assess 

how voluntary tribal water transfers could be used to improve the reliability of the water supply 

in the Basin.

As a final note, the Ten Tribes Partnership emphasizes that these options are designed for

voluntary tribal transfers only. In no case should the development of these options mandate 

transfers of any particular tribal resource from any of the member Tribes. The Ten Tribes 

Partnership invites BOR to enter into long-term discussions with the Ten Tribe Partnership to 

work through these various options. As an interim step, we would like to schedule a meeting as 

soon as possible between BOR and the Ten Tribes Partnership technical group to determine how 

best to analyze and pursue these options.

Appendix F13

Attachment B

Options Submitted by the

Inter Tribal Council of Arizona

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-1

Attachment B — Options Submitted by the 

Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona

Introduction

The water of the Colorado River and its tributaries is the lifeblood of tribal people and tribal 

communities and has been for millennia. Tribal people have lived along the banks of the River 

system, managing its flow and withstanding its vagaries, while building thriving civilizations in 

these arid lands.

To every tribe, water is life. It has a sacred value. It is not simply a commodity to be measured,

modeled, apportioned, bought and sold, argued about in the courts. Water is embedded in 

tribal culture. In many ways it is who tribal people are as human beings.

The tribal governments of Indian nations are sovereign governments. The United States has a 

government-to-government relationship with tribal governments. Tribes are not "stakeholders" 

with respect to the waters of the Colorado; they are governments with a right to participate on 

an equal basis with the federal government in establishing policy for the management of the 

River.

Today there are 30 federally-recognized Indian tribes within the boundaries of the Colorado 

River Basin. Twenty-two of these are located or have land in Arizona. Although the tribes 

differ in many ways, they are all united in a respect for water in all its forms.

Tribal water management occurs within a unique legal and institutional framework and is very 

closely linked to water rights. First in time, first in right -- the cornerstone of water law in 

Arizona and other Western states -- makes the aboriginal rights of tribes to water senior to those 

of users that arrived much later.

A century-old United States Supreme Court ruling forms an important legal basis for Indian 

water rights. In a 1908 decision in the case of Winters v. U.S., 207 U.S. 564 (1908), the Court held

that when the federal government creates an Indian reservation it implicitly reserves the right to 

use a sufficient amount of water to fulfill the purposes of the reservation.

This doctrine of federal reserved water rights for reservation areas was reaffirmed in a number 

of subsequent court decrees. For the tribes with land in Arizona, the 1963 decision of the United 

States Supreme Court in the case of Arizona v. California, 373 U.S. 546 (1963), is particularly 

important.

In its decision in that case, the high court said:

"It is impossible to believe that when Congress created the great Colorado 

River Indian Reservation and when the Executive Department of this 
Colorado River Basin

Water Supply and Demand Study

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 2

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

F13-B-2 December 2012

Nation created the other reservations they were unaware that most of the 

lands were of the desert kind - hot, scorching sands - and that water from 

the river would be essential to the life of the Indian people and to the 

animals they hunted and the crops they raised." Id. at 598-599.

The Court went on to assert that it would follow the decision in the Winters case, saying "We 

follow it now and agree that the United States did reserve the water rights for the Indians 

effective as of the time the Indian Reservations were created." Id. at 600.

The water rights of the five tribes along the mainstem of the Colorado River below Hoover Dam 

are quantified in the Court's rulings in the Arizona v. California case.

Over the last four decades, a number of tribes located off the mainstem of the Colorado River in 

central and southern Arizona have settled their claims for water rights through a negotiated 

process, affirmed in legislation passed by the United States Congress. In every case, Colorado 

River water supplied through the Central Arizona Project (CAP) canal has been part of the 

settlement.

A number of other tribes in Arizona have yet to obtain a quantification of their water rights, but 

do have allocations of CAP water. Most of the water involved cannot be used effectively by the 

tribes due to the restrictions on the use of CAP water and to the lack of tribal water distribution 

infrastructure. Still other tribes with land in Arizona have no quantification of their water 

rights and no allocation of CAP water, more than 100 years after the Winters decision.

There are eleven federally recognized tribal governments with trust land in Arizona whose 

water rights have yet to be completely adjudicated or quantified through litigation or 

settlements.

• The Havasupai Tribe

• The Hopi Tribe

• The Hualapai Tribe

• The Kaibab Band of Paiute Indians

• The Navajo Nation

• The Pascua Yaqui Tribe

• The San Carlos Apache Tribe

• The Tohono O'odham Nation

• The Tonto Apache Tribe

• The Yavapai-Apache Nation

• The White Mountain Apache Tribe, which has negotiated a settlement that is pending 

final approval by the adjudication court
Attachment B — Options Submitted by the 

Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 3

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-3

The Havasupai Tribe, Hopi Tribe, Hualapai Tribe, Kaibab Band of Paiute Indians and Navajo 

Nation are along or near the mainstem of the Colorado River as it flows through northern 

Arizona. The yet to be quantified claims of these tribes are sizeable.

In the case of the Navajo Nation, the claims affect not just rights to water apportioned to 

Arizona, but the Upper Basin states of Utah, Colorado and New Mexico as well. All of the 

reservation's 25,000 square miles are located within the Basin. Flowing through the northern 

portion of the reservation, the mainstem of the Colorado forms its western boundary. Major 

tributaries, the San Juan and Little Colorado Rivers, flow through Navajo tribal land.

Five tribes in Arizona have either Central Arizona Project (CAP) entitlements, but no 

settlements, or settlements for only part of their tribal lands:

• The Pascua Yaqui Tribe (CAP entitlement only, no settlement)

• The San Carlos Apache Tribe (CAP entitlement, partial settlement only)

• The Tohono O'odham Nation (CAP entitlement, partial settlement only)

• The Tonto Apache Tribe (CAP entitlement only, no settlement)

• The Yavapai-Apache Nation (CAP entitlement only, no settlement)

The Arizona Water Settlements Act of 2004 (AWSA) specifically reserves CAP water for use in 

future settlements. However, the amount reserved is not sufficient to meet the water rights 

claims of all the tribes involved. A very small quantity of mainstem water has also been 

reserved for a future settlement of tribal claims in Arizona.

It is essential that all tribal rights to the water of the Colorado River be included in full in the 

Basin Study, including the unquantified rights of tribes without settlements. The final 

report of the Study must reflect the fact that this water is tribal water and must be considered 

as such, whether currently quantified or not, whether currently used or not, whether 

currently leased or otherwise provided to others or not. It is not to be considered as water 

available to other users without tribal consent.

Appendix A lists the currently quantified rights of tribes with land in Arizona to Lower Basin 

mainstem and CAP water.

The Tribal Role in Charting the River's Future

Tribes must be full partners in any attempt to chart the future of the River.

Tribes hold rights to nearly three-quarters of the water covered by Arizona Priority 1 rights. 

Tribes hold entitlements to almost half of the water covered by long term CAP entitlements. 

Tribes in other states hold equally important and substantial rights to the water of the River and 

its tributaries.

Strategizing the future of the River is simply not meaningful without tribes at the table. A very 

substantial portion of the water involved is tribal water, no one else's.
Colorado River Basin

Water Supply and Demand Study

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 4

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

F13-B-4 December 2012

The history of the neglect of tribes and tribal rights in determining the future of the Colorado 

River has a long and sorry past. In some respects, it started in the negotiations that led to the 

1922 Colorado River Compact, the cornerstone for the "Law of the River." Though the decision 

in the Winters case was issued by the United States Supreme Count a decade-and-a-half earlier, 

tribes were not invited to those negotiations. The federal government and the Basin states 

signed the Compact. Tribes were not parties to it.

Article VII of the Compact states: "Nothing in this compact shall be construed as affecting the 

obligations of the United States of America to Indian tribes." Notwithstanding this language, in 

the years that followed the adoption of the Compact the settlement of tribal claims to the River's 

water -- fundamental to any allocation of that water -- languished as the federal government 

and the states went about deciding how to apportion the River's water.

The federal government and all its agencies, including the Department of the Interior and its 

Bureau of Reclamation, are responsible for upholding the trust responsibility of the federal 

government to tribal governments.

The Bureau of Reclamation needs to adopt a comprehensive policy addressing how it will 

fulfill its trust responsibilities. That policy should incorporate the fundamental principles of 

the government-to-government relationship and a consultation process which involves the 

resolution of policy issues, not merely conducting listening sessions. 

The policy should speak to the protection of trust assets, the resolution and protection of tribal 

water rights, the full use of the Bureau's authority to delegate functions and provide financing 

to tribes under all provisions of the Indian Self-Determination Act, respect for sacred sites and 

tribal religious practices and culture, the full implementation of federal policies with respect to 

human remains and the return of cultural items, the implementation of environmental 

programs including those under the Endangered Species Act, along with the opportunity to 

participate fully in Reclamation programs and activities.

The Colorado River Basin Study was created without tribes involved. That must be corrected 

and not repeated in any future discussions involving the management of the River.

Further, tribes must be involved as sovereign nations, not as "stakeholders." They have a right 

to this status on an equal basis with the federal government.

The Basin Study provides an occasion to move toward the full integration of tribal governments 

in the governance of the River. The agreement of the US Bureau of Reclamation (BOR) to meet 

with the major River tribes on an ongoing basis during the final phase of the Study, along with 

its participation in other meetings, such as those held by Inter Tribal Council of Arizona, are 

important first steps in this direction.

An inter-governmental forum to discuss and resolve current and future issues affecting the 

management of the River should be established that includes tribes as equal partners with 

the federal and state governments.
Attachment B — Options Submitted by the 

Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 5

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-5

Strategies for a Way Forward

There are a number of strategies that address tribal issues in the future of the River, issues that 

should be included in the final report of the Basin Study. These strategies include, but are not 

limited to the ones discussed below.

Resolution of Tribal Claims

All discussion of water on the River must take into account the fact that tribes have claims to the 

River's water that have yet to be quantified. Future tribal demand, and therefore total demand, 

cannot be accurately modeled while these claims remain outstanding.

The Court system of the state of Arizona has failed tribes in its duties with regard to the 

adjudication of federal reserved water rights. The Gila River and Little Colorado River general 

stream adjudications have been pending for more than 30 years. Not one decreed Indian water 

right has been issued, other than the ones brought to the adjudication court as a result of 

negotiated settlements. With the surge in the growth of the non-Indian population, the 

demands on the water to which tribes have rights intensifies. The tribes are entitled to have 

their water rights quantified and protected. It is the solemn obligation of the government of the 

United States to insure that this happens.

Expediting the resolution of tribal claims must be a major priority. The Interior Department 

must take all necessary steps to facilitate this process.

A number of settlement negotiations are or have been underway. However, there are barriers 

to the conclusion of those negotiations, at least some of which can be removed.

A major barrier involves the acquisition of water needed to settle tribal claims.

In Arizona discussions are ongoing to identify sources of water and to develop appropriate 

institutional arrangements and secure funding to acquire and transport water to meet future 

non-Indian municipal and industrial needs. The Central Arizona Water Conservation District 

has done this, both to satisfy its existing legal obligations and to supplement CAP project water. 

The Arizona Water Resources Development Commission is doing this, in part to deal with 

current and future needs of communities in the more rural parts of the state.

Yet there appears to be no effort to identify and acquire sources of water to satisfy tribal claims.

The US Bureau of Reclamation and the affected tribes should work together to develop a 

water acquisition strategy and implementation plan to provide water to satisfy all currently 

unquantified tribal rights. This might involve the creation of an entity to pursue this goal. The 

affected tribes should have majority representation on the governing body of such an entity. It 

should have the legal power to acquire water rights, and, as appropriate, develop the 

infrastructure to make it available for tribal use.

A second issue in the resolution of pending tribal claims involves the limitation on the amount 

of CAP water reserved for future settlements.
Colorado River Basin

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The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 6

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

F13-B-6 December 2012

When Congress passed the Arizona Water Settlements Act (AWSA), it attempted to resolve this 

issue. Section 104(a)(1)(A)(iii) of the Act provides that 67,300 acre-feet of the non-Indian 

agricultural (NIA) priority water available to CAP is to be available for reallocation to Indian 

tribes. Of that amount, 23,782 acre-feet was allocated to the White Mountain Apache Tribe in its 

recently concluded negotiations, now pending final settlement in the adjudication court. A 

major portion of the remaining 43,518 acre-feet would have been used in a proposed but not 

concluded Navajo-Hopi settlement.

The limitation on the amount of CAP NIA water available for future settlements has the 

effect of constraining negotiations to resolve pending claims and should be increased. 

Moreover, simply awarding CAP NIA water under the current priority system is not a 

guarantee that tribes will have access to "wet" water in the future. With the very real risk of a 

shortage of water on the River in future years, the supply available to CAP may be curtailed. 

NIA water, with its lower priority, may cease to be available. Even NIA water "firmed" to 

Municipal and Industrial (M&I) priority status will retain that status for just 100 years. Tribes 

have been here for millennia, and will continue to be here for long after any firming agreement 

ends.

Current law provides that the US Secretary of the Interior, in consultation with Arizona Indian 

tribes and the state, prepare a report to Congress by December 31, 2016. That report is to 

contain, among other things, an assessment of critical water needs on reservations without 

settlements. Interior and tribes need to start preparations to meet this reporting requirement 

and use it as an opportunity to examine an increase in the ceiling set in Section 104(a)(1)(A)(iii) 

of AWSA.

Enabling Tribes to Use All the Water to Which They Have Rights

Tribes with adjudicated water rights, including the mainstem tribes, are not always in a position 

to divert all the water to which they have rights. In recent years, mainstem tribes with rights to 

the Arizona apportionment of Colorado River water have diverted nearly all of the water to 

which they have rights. The small remainder is not credited to those tribes in any way.

When the Interim Shortage Guidelines were finalized in 2007, states were provided with a 

mechanism -- Intentionally Created Surplus (ICS) -- that encouraged them to conserve water 

which they are able to draw down in future years. The ICS idea started as a demonstration 

project that was then incorporated into the Interim Shortage Guidelines.

The ICS mechanism has proven to be popular with the states. According to the 2010 Colorado 

River Accounting and Water Use Report for the Lower Basin states, there was an end of year 

balance in in the various ICS accounts totaling 815,341 acre-feet.

Tribes have been given no comparable incentive to conserve water. Their only option is to draw 

down as much water as they can within the caps in their settlements. All the water to which 

tribes have rights that is not drawn down is lost to the tribe.

There should be an incentive for tribes to conserve water to which they have rights.
Attachment B — Options Submitted by the 

Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 7

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-7

That incentive might be created as a demonstration program for a Tribal Conservation Reserve 

(TCR). The details of such a plan should be worked out by interested tribes and BOR.

For purposes only of illustrating the concept, such details might include the following:

• In accordance with a plan, developed voluntarily by a tribe, a portion of the 

water that the tribe is eligible to divert in a given year would be held in Lake 

Mead in the form of TCR credits. The tribe could then divert that water in a 

future year by calling on its credits.

• A tribe with TCR credits could use its credits for the diversion of water to its own 

reservation. In addition, by mutual consent with another tribe with mainstem 

rights, a tribe with storage credits could elect to exchange its credits with another 

tribe for that tribe's use.

• Such exchanges would be permitted only among tribes, and only involving 

water accounted for in the same state's apportionment.

• The release of water reducing TCR credits would not be considered as "surplus" 

water as its withdrawal in the future year would be in lieu of its withdrawal in 

the year in which the credits were accrued.

Such a TCR demonstration program would have a number of benefits. The water conserved 

would be available to support the elevation of Lake Mead. No water rights would be exceeded. 

Only water to which tribes have rights would be affected. The demonstration would provide a 

cost-efficient, non-structural alternative to on-reservation underground storage.

There is an additional aspect of this issue. That involves the reuse of agricultural water.

Tribes currently return very significant amounts of irrigation water to the River. This is water 

that the tribes have a right to divert and put to their own use for agricultural or non-agricultural 

purposes, but instead is considered as non-tribal water as soon as it flows into the River.

In non-Indian communities, agricultural water reuse is regarded as one of a variety of options 

for obtaining additional water to support future community needs. This is not currently the 

case with respect to tribal communities. 

Creating a Tribal Agricultural Water Reuse demonstration project would address this issue. 

The details of such a plan should be worked out by interested tribes and BOR.

For purposes only of illustrating the concept, such details might include the following:

• In accordance with a plan, developed voluntarily by the tribe, the amount of 

agricultural drainage water produced in any given year would be given storage 

credits in an on-River reservoir. The tribe could redeem those credits in a future 

year for community and economic development purposes within the 

reservation's borders.
Colorado River Basin

Water Supply and Demand Study

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 8

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

F13-B-8 December 2012

• Storage credits for agricultural reuse water would be accrued year by year based 

on the calculated volume of such water.

• The tribe could redeem its credits in any future year in accordance with its plan, 

for purposes described in that plan. Eligible purposes might include:

 Municipal needs in communities within the exterior boundaries of the 

reservation.

 On-reservation economic development, including power generation.

 On-reservation development of additional agricultural land.

 Transfer of the use of credits to other tribes with the consent of all the 

tribes involved.

Such a demonstration program would have a number of benefits. Tribes would be able to make 

full use of their existing water rights. The demonstration project would provide water for 

future reservation development without any increase in existing tribal water rights. The 

demonstration would provide a cost-efficient, non-structural alternative to on-reservation 

underground storage of agricultural drainage water.

Colorado River Water and Tribes with CAP Entitlements

Eleven of the tribes in Arizona currently have entitlements to Colorado River water delivered 

through the Central Arizona Project canal. They include tribes whose lands are within the 3-

county CAP service area, as well as tribes in other areas of the state that are not able to take 

direct delivery of water from the canal.

Since the first of the recent tribal settlements -- that of the Ak-Chin Indian Community in 1978 --

CAP water has consistently been awarded in lieu of water that once flowed across or under 

tribal lands. The promise to tribes has been: surrender your claims to the water that was yours 

and the federal government will insure that you have water to meet your needs, water provided 

through the CAP canal.

This promise continues into the present. The White Mountain Apache Tribe's water settlement, 

ratified by Congress in December 2010 and currently pending final approval, involves CAP 

water. A potential settlement of the claims of the Navajo Nation and the Hopi Tribe would 

have drawn on CAP water.

That promise -- to supply CAP water in lieu of other surface water and groundwater in 

satisfaction of tribal claims -- is now in danger. 

Tribes with CAP entitlements may have rights to the water, but are responsible for costs related 

to delivering that water.

CAP water rates have escalated sharply in recent years. From 2000 to 2012, the posted CAP 

rates for the delivery of Indian water have increased 126%. In just the last five years, the rates 

have jumped 34%. 
Attachment B — Options Submitted by the 

Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 9

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-9

The steady and substantial increase in the cost of CAP water to which tribes have rights --

rights won after years of negotiation and struggle in the courts -- is a serious issue. Future 

federal policy on Colorado River water must insure that CAP water in all tribal settlements is 

affordable in order to insure the viability of tribal agriculture and the water security of tribal 

homelands into the future.

Power costs are the matter of most immediate concern. The power to move Colorado River 

water far inland through the CAP canal is produced by the Navajo Generating Station (NGS). 

The owners of the NGS, including BOR, face potentially substantial upgrades of the air 

pollution control equipment at the plant's coal-fired units. Such upgrades could be required by 

the US Environmental Protection Agency to deal with Clean Air Act issues. A decision on this 

matter is expected in the near future.

A study commissioned by the US Department of the Interior and currently under review 

projects that the cost to tribes that receive CAP water could jump by as much as 32% above 

current rates if NGS is required to install high end pollution control equipment.

This one-third increase assumes that the plant stays in operation.

Should the owners of NGS conclude that their economic interests are better served by closing 

the plant instead of installing EPA-required high end pollution control equipment, then the 

increased cost to tribes of CAP water could be in the vicinity of 66%.

Tribes are not in a position to afford such increases. As the officials of the Gila River Indian 

Community have pointed out, "This is like losing our water all over again."

Environmental requirements, imposed through no fault of the tribes, must not be allowed to 

deprive tribes of the water to which they have rights. The federal government must not 

permit such requirements to go forward or, alternatively, provide a funding stream or other 

arrangement that insures that tribes can afford to use all the water to which they have rights.

Support for Tribal Water Management Functions

Water conservation and increases in the efficiency of agricultural, municipal and other water 

use in reservation areas are high priority issues for all tribes. Making the water that is available 

go further enhances tribal rights.

Robust tribal water management capability is essential to serve all these purposes. In turn, this 

requires appropriate institutional structures, technical expertise and access to funding.

With a limited tax base, funding is a serious obstacle for tribes. Tribal governments need to 

draw on a variety of federal programs to provide that funding. However, federal and state 

programs that could provide the necessary resources impose requirements that make them hard 

to access or put them completely out of the reach of tribes. 

Barriers to tribal participation include:

• Requirements for explicit waivers of sovereign immunity.
Colorado River Basin

Water Supply and Demand Study

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 10

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

F13-B-10 December 2012

• Cost sharing requirements with limited or no possibility of exceptions for needy 

communities.

• Inability to support preliminary engineering and environmental review reports 

required to apply for construction financing.

• Lack of preference for communities with the most severe need and least ability to 

pay.

In addition, there currently is no specific program to provide flexible funding for tribal 

capacity building in the water management field.

BOR should support a technical study of barriers to tribal participation in federal 

programs that support water resource management and the development of water 

infrastructure.

Addressing Colorado River Water Supply-Demand Imbalances

Work done during earlier phases of the Colorado River Basin Study has projected that 

the supply of water in the River will not meet the demand for that water in the years 

ahead. The most recent estimates indicate a shortfall in the vicinity of 2.0 million acrefeet in 2035 and 3.6 million acre-feet or more in 2060. Though these numerical estimates 

are recent, it has been known for years that the water in the River is over allocated.

The first principle in addressing any projected imbalance is that tribal rights to water 

must be recognized and respected. No option or strategy which would diminish 

tribal water rights, quantified or not, is acceptable, nor is any option or strategy which 

would reduce any tribe's right to make full use of the water to which the tribe has 

rights.

Tribes are sovereign nations. Under the Winters doctrine, tribes are to have complete 

control of all beneficial uses of their land and water without the interference of the states 

in which their reservations are located. Tribal rights must be fully accounted for in the 

Basin Study.

Options and strategies to address future imbalances generally fall into two categories: 

demand management and supply augmentation.

Demand management requires a recognition of limits.

Over the millennia of their life in what is now the American Southwest, tribal people 

have dealt with the limits of a highly variable water supply. The vagaries of the natural 

supply led to a variety of forms of adaptation. Tribes survived by understanding limits. 

The more recently settled non-Indian communities must likewise understand and deal 

with these limits.

Limits on tribal water have been imposed by nature and by man. The latter include 

ceilings on rights to water that are a universal feature of tribal water settlements. The 
Attachment B — Options Submitted by the 

Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 11

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-11

terms of tribal settlements do not support unlimited expansion in water use based on 

on-reservation population growth resulting from in-migration or on any other factors.

Future population growth and economic development in the non-Indian communities of the 

Colorado River Basin must be conditioned by the federal, state and local governments on the 

availability and sustainability of the water resources necessary to support such growth and 

development.

Supply augmentation involves a number of options. This paper will address just one, one 

which has a direct relationship to several tribes in the Basin.

Much of the runoff into the Colorado River originates as snowmelt in the Colorado Rockies. 

The ability of the snow pack to generate ample runoff and at the appropriate times in the spring 

is, in turn, affected by how pristine the surface of the snow cover is.

Windborne dust has a substantial effect on runoff. The darker the snow surface, the more it 

absorbs sunlight, heating the surface and producing an earlier runoff. Evapotranspiration from 

plants increases, reducing runoff.

The source of much of the dust causing this chain reaction is soil from the Colorado Plateau. 

For example, as the climate has changed, sand dunes on the Navajo reservation have grown 

rapidly and are becoming mobile. The ongoing studies of US Geological Survey geologist Dr. 

Margaret Hiza Redsteer provide dramatic evidence of how climate change impacts the land and 

its inhabitants. Her work sheds light not only on soil-precipitation interactions, but on how 

those dynamics can impact cultural ways.

An article published in 2010 in the Proceedings of the National Academy of Sciences underscored the 

potential for increasing runoff into the River by reducing the dust reaching the snowpack, much 

of which originates on the Colorado Plateau. The team of scientists performing the research 

estimated that over half of the overdraft from Lake Mead that occurred during the 2000 to 2009 

time frame resulted from a shortfall in runoff that could be attributed to dust deposition on the 

Rockies snowpack.

The abstract of that article, "Response of Colorado River runoff to dust radiative forcing in 

snow," concluded:

"The potential to reduce dust loading through surface stabilization in the deserts 

and restore more persistent snow cover, slow runoff, and increase water 

resources in the Upper Colorado River Basin may represent an important 

mitigation opportunity to reduce system management tensions and regional 

impacts of climate change."

Stabilization of the soil on portions of the Navajo reservation and nearby lands at Hopi 

shows promise of significantly increasing the runoff in the Colorado River system and 

should be supported in the report of the Basin Study.
Colorado River Basin

Water Supply and Demand Study

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 12

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

F13-B-12 December 2012

Conclusion

Tribes are essential parties to any discussions of the future of the Colorado River system. Tribal 

people used its flow to thrive in an arid environment long before others did. Tribes hold a 

major portion of the rights to the River's flow in Arizona, as well as other states.

Tribes must be made a full partner in such discussions. They were not when the Colorado 

River Basin Study originated. That must be corrected as it concludes and not repeated in the 

future.

A full government-to-government partnership should be formed to discuss and resolve future 

issues, a partnership among tribal governments, the federal government and the state 

governments.

In analyzing the future health of the Colorado River system, all tribal rights to the water of the 

system must be respected. This includes rights that are currently quantified and rights that are 

not; rights to water that is currently used and water that is not currently used; rights to water 

that is leased or otherwise made available to others and water that is not. Tribal water is tribal 

water and must not be assumed to be available to others without tribal consent.

This report has suggested a variety of ways to accomplish these objectives:

• Insure that the resolution of all tribal claims proceed expeditiously and that there 

is water available to satisfy these claims.

• Insure that tribes with rights to water be able to beneficially use all the water to 

which they have rights.

• Insure that the water from the River delivered through the CAP canal 

incorporated in tribal water settlements remains available and affordable.

• Remove barriers to tribal access to federal and other programs that can 

strengthen tribal water management capability.

• All communities must respect limits to the quantity of water in the system, not 

just tribal communities.

• Augment the streamflow in the River through a soil stabilization program on the 

Colorado Plateau, including tribal lands.

The future of the Colorado River system is what we make it. Tribes have much they can and 

will contribute to this process.

Revision date: March 1, 2012
Attachment B — Options Submitted by

the Inter Tribal Council of Arizona

The Future of the Colorado River System:

A Tribal Perspective from Arizona Page 13

Inter Tribal Council of Arizona, Tribal Leaders Water Policy Council, March 1, 2012

December 2012 F13-B-13

Appendix A

Colorado River Currently Quantified Tribal Water Rights/Entitlements - Tribes with Land in Arizona

Lower Basin - Mainstem and CAP Water Only

Mainstem & CAP Arizona California Nevada

Central 

Arizona

Tribe Grand Total Apportionment Apportionment Apportionment Project (CAP)

Ak-Chin Indian Community 85,000 50,000 35,000

Cocopah Tribe 10,847 10,847

Colorado River Indian Tribes 719,248 662,402 56,846

Fort McDowell Yavapai Nation 18,233 18,233

Fort Mojave Indian Tribe 132,789 103,535 16,720 12,534

Gila River Indian Community 328,800 328,800

Havasupai Tribe Amount currently unquantified

Hopi Tribe 6,028 6,028 Contract amount only, no settlement

Hualapai Tribe Amount currently unquantified

Kaibab Band of Paiute Indians Amount currently unquantified

Navajo Nation Amount currently unquantified

Pascua Yaqui Tribe 500 CAP entitlement only, no settlement 500

Quechan Indian Tribe 77,966 6,350 71,616

Salt River Pima-Maricopa Indian 

Community 35,300 22,000 13,300

San Carlos Apache Tribe 64,145 64,145

Tohono O'odham Nation 74,000 74,000

Tonto Apache Tribe 128 CAP entitlement only, no settlement 128

White Mountain Apache Tribe 25,000 Amount in settlement, pending final approval 25,000

Yavapai-Apache Nation 1,200 CAP entitlement only, no settlement 1,200

Yavapai-Prescott Tribe 500 500

Reserved for Future Settlements 47,018 3,500 43,518

Totals 1,626,702 864,662 145,182 12,534 604,324

Notes: All water in acre-feet, measured in diversion amounts. See text for list of tribes with no settlements or only partial settlements.

Table provided only to indicate scope of currently quantified rights/entitlements. See individual decrees/settlements for complete terms. Ak-Chin 

amount is as specified for a year in which surplus water is available and excludes amount of water transfer to San Carlos.