QUALITY OF WATER 

COLORADO RIVER BASIN 

Progress Report No. 24 

U.S. Department of the Interior 

Bureau of Reclamation 

Upper Colorado Region 2013
Mission Statements 

The U.S. Department of the Interior protects and manages the nation’s natural resources 

and cultural heritage; provides scientific and other information about those resources; and 

honors its trust responsibilities or special commitments to American Indians, Alaska 

Natives, and affiliated island communities. 

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. 
ii 

TABLE OF CONTENTS 

MISSION STATEMENTS .................................................................................................................. i

SUMMARY ...................................................................................................................................... 1

CHAPTER 1 - INTRODUCTION ..................................................................................................... 5

AUTHORIZATION FOR REPORT .......................................................................................... 5

LEGAL ASPECTS ................................................................................................................... 6

Water Quantity .................................................................................................................. 6

Water Quality .................................................................................................................... 7

CHAPTER 2 – SALINITY CONDITIONS ...................................................................................... 11

CAUSES OF SALINITY ......................................................................................................... 11

HISTORIC SALINITY CONDITIONS ..................................................................................... 13

FACTORS INFLUENCING SALINITY ................................................................................... 14

Streamflow ...................................................................................................................... 14

Reservoir Storage ........................................................................................................... 15

NATURAL VARIATION IN SALINITY .................................................................................... 18

AGRICULTURAL SOURCES OF SALINITY ......................................................................... 18

WATER USE BY MUNICIPAL & INDUSTRIAL USERS ....................................................... 19

ENERGY DEVELOPMENT ................................................................................................... 20

Oil and Natural Gas ........................................................................................................ 21

FUTURE WATER DEVELOPMENT ...................................................................................... 22

COMPLIANCE WITH THE SALINITY STANDARDS ............................................................ 25

SALINITY CONTROL ............................................................................................................ 26

CHAPTER 3 – TITLE I SALINITY CONTROL PROGRAM .......................................................... 29

Coachella Canal Lining ................................................................................................... 29

Protective and Regulatory Pumping ............................................................................... 29

Yuma Desalting Plant ..................................................................................................... 29

Wellton-Mohawk Irrigation and Drainage District (WMIDD) ........................................... 29

CHAPTER 4 - TITLE II SALINITY CONTROL PROGRAM .......................................................... 31

U.S. BUREAU OF LAND MANAGEMENT ............................................................................ 32

Program Administration .................................................................................................. 33

State Activities Since Last Progress Report ................................................................... 33

U.S. DEPARTMENT OF AGRICULTURE (USDA/NRCS) ....... .................................... 39 

New Salinity Projects and Investigations ....................................................................... 39
iii 

TABLE OF CONTENTS (CONTINUED)

Monitoring and Evaluation .............................................................................................. 41

Active Salinity Control Projects ....................................................................................... 41

U.S. BUREAU OF RECLAMATION ...................................................................................... 45

Basinwide Salinity Control Program (Basinwide Program) ............................................. 45

Basin States Program (BSP) ............................................................................50 

Paradox Valley Unit ........................................................................................................ 51

Colorado River Basin Salinity Control Program Summary Data ..................................... 54

REFERENCES CITED .................................................................................................................. 59

GENERAL REFERENCES ........................................................................................................... 63

APPENDIX A – SALINITY MONITORING STATION INFORMATION ........................................ 69

APPENDIX B - SALT LOAD 2012 UPDATE FOR THE 20 STATIONS ................................. 73

APPENDIX C - 20 STATION FLOW AND SALT TDS OVER TIME ................................... 119 
iv 

TABLES 

Table 1 - Quantified Sources of Salt Loading ............................................................................... 12 

Table 2 - Upper Basin Depletion Projections ............................................................................... 23

Table 3 - Lower Basin Depletion Projections ............................................................................... 24

Table 4 - Salinity Control Requirements and Needs through 2030 ............................................... 27 

Table 5 - WMIDD Irrigation Efficiency ........................................................................................... 30 

Table 6 - BLM Salt Retention Estimates for FY 2006 - 2012 ........................................................ 39 

Table 7 - Active Salinity Control Projects ...................................................................................... 41 

Table 8 - USDA Salinity Control Unit Summary through 2012 ...................................................... 44 

Table 9 - Paradox Well Injection Evaluation ................................................................... 53 

Table 10 - Summary of Federal Salinity Control Programs ........................................................... 55 

Table 11 - Summary of Colorado River Basin Salinity Control Program Funding ........................ 57 

Table 12 - Reclamation Basinwide Salinity Control Program Summary ....................................... 58 

Table 13 – UCRB Agricultural Salinity Control Summary (tons) 2012 ......................................... 58 

Table A1 – Characteristics of the 20 Salinity Monitoring Stations ................................................ 70 

Table B1 – Salinity Load Regression Model Coefficients ........................................................... 118 

FIGURES 

Figure 1 - Sources of Salinity ....................................................................................................... 11 

Figure 2 - Percentage of Salinity Damages ................................................................................... 13

Figure 3 - Colorado River Salinity at Lower Basin Compact Points .............................................. 14 

Figure 4 - Mainstem Flow and Salinity .......................................................................................... 15 

Figure 5 - Effect of Glen Canyon Dam on Colorado River Salinity at Lees Ferry ......................... 16 

Figure 6 - Lake Powell Forebay near Dam, Dec 1964 to Dec 2012 Salinity Conc, mg/L ............. 16 

Figure 7 - Lake Powell Inflow and Outflow Salt Concentration, mg/L ......................................... 17 

Figure 8 - Photo of Coal Bed Methane Well .................................................................................. 21

Figure 9 - Historic and Projected Water Uses ............................................................................... 25

Figure 10 - 2012 Estimated Salinity Control Progress: BOR, NRCS & BLM ............................... 27 

Figure 11 - Map of Title I Salinity Control Projects ....................................................................... 29 

Figure 12 - Map of Title II Salinity Control Projects ....................................................................... 31 

Figure 13 - NRCS onfarm Salt Controlled through 2012 .............................................................. 45 

Figure 14 - Price-San Rafael Irrigation Improvements .................................................................. 46 

Figure 15 - Salinity in Uinta Basin Unit Area ................................................................................. 47 
v 

FIGURES (Continued) 

Figure 16 - Paradox Valley ........................................................................................................... 52 

Figure 17 - Schematic of Paradox Project ..................................................................................... 52 

Figure A1 - Colorado River Water Quality Monitoring Stations .................................................... 69 

Figure A2 - Colorado River Flow and Salinity ............................................................................... 71

Figure C1 - Flow and TDS over time for sites 1-4 ...................................................................... 120 

Figure C2 - Flow and TDS over time for sites 5-8 ...................................................................... 121 

Figure C3 - Flow and TDS over time for sites 9-12 ......................................................... 122 

Figure C4 - Flow and TDS over time for sites 13-16........................................................ 123 

Figure C5 - Flow and TDS over time for sites 17-20 ........................................................124 
1 

SUMMARY 

The Colorado River and its tributaries provide water to about 36 million people and 

irrigation water to nearly 5.5 million acres of land in the United States (Bureau of 

Reclamation, 2012a; Cohen, 2011). The river also serves about 3.3 million people and 

500,000 acres in Mexico (Cohen, 2011). The effect of salinity is a major concern in both 

the United States and Mexico. Salinity 

damages in the United States are presently 

about $295 million per year at 2010 salinity 

concentrations. This biennial report on the 

quality of water in the Colorado River Basin is 

required by Public Laws 84-485, 87-483, and 

the Colorado River Basin Salinity Control Act 

(Salinity Control Act) (Public Law 93-320, as 

amended by Public Laws 98-569, 104-20, 

104-127, and 106-459). 

The Salinity Control Act authorizes the 

Secretaries of the U.S. Department of the 

Interior (Interior) and U.S. Department of 

Agriculture (USDA) to enhance and protect the quality of water available in the Colorado 

River for use in the United States and the Republic of Mexico. 

Title I of the Salinity Control Act authorized the construction and operation of a desalting 

plant, brine discharge canal, and other 

features to enable the United States to 

deliver water to Mexico having an average 

salinity no greater than 115 parts per 

million (ppm) plus or minus 30 ppm over 

the annual average salinity of the Colorado 

River at Imperial Dam. The Title I program 

(administered by the Bureau of 

Reclamation [Reclamation]) continues to 

meet the requirements of Minute No. 242 of 

the International Boundary and Water 

Commission, United States and Mexico. 

Title II of the Salinity Control Act authorizes the Secretary of the Interior (Secretary) and 

the Secretary of Agriculture to implement a broad range of specific and general salinity 

control measures in an ongoing effort to prevent further degradation of water quality to 

meet the objectives and standards set by the Clean Water Act. 

In 1995, Public Law 104-20 authorized an entirely new way of implementing salinity 

control. Reclamation’s Basinwide Salinity Control Program opened the program to 

competition through a “Request for Proposal” process, which greatly reduced the cost of 

salinity control by selecting the most cost effective projects. However, the price of 

salinity control is expected to increase in the future as the more cost effective projects are 

completed. 

Salinity damages to municipal water pipe. 

Salinity damages to crop production. 
2 

The Colorado River Basin Salinity Control Forum (Forum) in accordance with the 

requirements of the Clean Water Act, prepared the “2011 Review, Water Quality 

Standards for Salinity, Colorado River System” (Review). The Review reported that by 

2030 a target of 1.85 million tons per year of salt will need to be controlled from entering 

the Colorado River in order to meet the water quality standards in the Lower Basin, 

below Lees Ferry, AZ. The combined Reclamation, USDA - Natural Resources 

Conservation Service & BLM salinity reduction reported for 2012 shows that the 

Colorado River Basin Salinity Control Program (Program) is currently controlling over 

1,295,000 tons of salt per year. In order to meet the 1.85 million tons of salt per year 

goal, it will be necessary to fund and implement potential new measures which ensure the 

removal of an additional 555,000 tons by 2030. The Forum stated that in order to achieve 

this level of salt reduction, the federal departments and agencies would require the 

following capital funding: Reclamation appropriation - $17.5 million per year (bringing 

the total Reclamation program with $7.5 million cost-sharing to $25 million per year); 

and USDA EQIP appropriation - $13.8 million per year (bringing the total on-farm 

program to $19.7 million per year with Basin states parallel program). Beginning in 2005, 

BLM began a comprehensive program to minimize the salt loading from BLM lands in 

the Colorado River basin. BLM salinity funding from Congress began in FY 2006. 

With the reported existing salt controlled, and assuming no reduction of the existing 

salinity control projects, then nearly 31,000 tons of new or additional controls will need 

to be implemented each year to maintain the standards with increased future water 

development. This Program goal is the combined target for the participating agencies 

within Interior and USDA. The participating agencies reported to the Colorado River 

Basin Salinity Control Advisory Council, showing that the agency’s efforts have been 

able to exceed the program’s target over the past several years. 

Since water year 2005, the Upper Colorado River Basin has experienced significant year 

to year hydrologic variability. The unregulated inflow to Lake Powell, which is a good 

measure of hydrologic conditions in the Colorado River Basin, has averaged a water year 

volume of 10.22 maf (94% of average (period 1981-2010)) during the period from 2005 

through 2012. The hydrologic variability during this period has been from a low water 

year unregulated inflow volume of 4.91 maf (45% of average) in water year 2012 to a 

high water year unregulated inflow volume of 15.97 maf (147% of average) in water year 

2011. 

Overall reservoir storage in the Colorado River Basin has increased by over 4 maf since 

the beginning of water year 2005 and this is an improvement over the persistent drought 

conditions during water years 2000 through 2004. From the beginning of water year 

2005 to the end of water year 2012, the total reservoir storage in the Colorado River 

Basin increased from 29.8 maf (50% of capacity) to 33.9 maf (57 % of capacity). 

However, during this time, total Colorado Basin storage experienced year to year 

increases and decreases in response to wet and dry hydrology. Salinity concentration has 

varied during this time period (with a downward trend), but has not exceeded the numeric 

salinity criteria on the Colorado River below Hoover Dam, Parker Dam and at Imperial 

Dam; 723, 747 & 879 mg/L respectively. Reclamation’s short term future salinity 

modeling scenarios indicate that the numeric salinity criteria should be maintained even 
3 

with an additional 1-2 years of drought. The salinity criteria could have been exceeded in 

2005 - 2007 without the salinity control program and other salt reductions. Nevertheless,

salinity damages are still very high at the 2011 salinity levels. These hydrologic 

conditions are providing new data, which will eventually reduce the uncertainty in 

salinity forecasting. 
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5 

CHAPTER 1 – INTRODUCTION 

The Bureau of Reclamation (Reclamation) of the U.S. Department of the Interior 

prepared this report in cooperation with State water resource agencies and other Federal 

agencies involved in the Colorado River Basin Salinity Control Program (Salinity 

Control Program). This Progress Report 24 is the latest in a series of biennial reports that 

commenced in 1963. 

AUTHORIZATION FOR REPORT 

The directive for preparing this report is contained in four separate public laws. 

Public Law 84-485 states: 

Section 15 –“The Secretary of the Interior is directed to continue studies and 

make a report to the Congress and to the States of the Colorado River Basin on 

the quality of water of the Colorado River,” 

Section 5c – “All revenues collected in connection with the operation of the 

Colorado storage project and participating projects shall be credited to the Basin 

Fund, and shall be available, without further appropriation, for (1) defraying the 

costs of operation, maintenance, & replacement of, and emergency expenditures 

for, all facilities”. The ongoing water quality monitoring, studies, and report are 

considered part of the normal operation of the project and are funded by the Basin 

Fund.” 

Public Law 87-483 states: 

Section 15 - “The Secretary of the Interior is directed to continue his studies of 

the quality of water of the Colorado River System, to appraise its suitability for 

municipal, domestic, and industrial use and for irrigation in the various areas in 

the United States in which it is used or proposed to be used, to estimate the effect 

of additional developments involving its storage and use (whether heretofore 

authorized or contemplated for authorization) on the remaining water available for 

use in the United States, to study all possible means of improving the quality of 

such water and of alleviating the ill effects of water of poor quality, and to report 

the results of his studies and estimates to the 87th Congress and every 2 years 

thereafter.” 

Public Law 87-590 states that January 3 would be the submission date for the report. 

Public Law 93-320 states: 

“Commencing on January 1, 1975, and every 2 years thereafter, the Secretary 

shall submit, simultaneously, to the President, the Congress, and the Advisory 

Council created in Section 204(a) of this title, a report on the Colorado River 

salinity control program authorized by this title covering the progress of 

investigations, planning, and construction of salinity control units for the previous 
6 

fiscal year; the effectiveness of such units; anticipated work needed to be 

accomplished in the future to meet the objectives of this title, with emphasis on 

the needs during the 5 years immediately following the date of each report; and 

any special problems that may be impeding progress in attaining an effective 

salinity control program. Said report may be included in the biennial report on the 

quality of water of the Colorado River Basin prepared by the Secretary pursuant 

to section 15 of the Colorado River Storage Project Act (70 Stat. 111; 43 U.S.C. 

602n), section 15 of the Navajo Indian Irrigation Project and the initial stage of 

the San Juan-Chama Project Act (76 Stat. 102), and section 6 of the 

Fryingpan-Arkansas Project Act (76 Stat. 393).” 

LEGAL ASPECTS 

Water Quantity 

Colorado River water was apportioned by the Colorado River Compact of 1922, the 

Boulder Canyon Project Act of 1928, the Water Treaty of 1944, the Upper Colorado 

River Basin Compact of 1948, and the United States Supreme Court (Arizona v. 

California et al., 1963). 

The Colorado River Compact divided the Colorado River Basin between the Upper and 

Lower Basins at Lee Ferry (just below the confluence of the Paria River), apportioning to 

each use of 7.5 million acre-feet (maf) annually. In addition to this apportionment, the 

Lower Basin was given the right to increase its beneficial consumptive use by 1 maf per 

year. The compact also contains provisions governing exportation of Colorado River 

water. The Water Treaty of 1944 obligates the United States to deliver to Mexico 1.5 maf 

of Colorado River water annually, absent treaty surplus or shortage conditions. 

Upper Colorado Use - The Upper Colorado River Basin Compact of 1948 divided and 

apportioned the water apportioned to the Upper Colorado River Basin by the Colorado 

River Compact, allocating to Arizona 50,000 acre-feet annually, with the remaining 

water allocated to Upper Colorado River Basin States as follows: 

 Colorado 51.75 percent 

 New Mexico 11.25 percent 

 Utah 23 percent 

 Wyoming 14 percent 

Lower Colorado Use - States of the Lower Colorado River Basin did not agree to a 

compact for the apportionment of waters in the Lower Colorado River Basin; in the 

absence of such a compact Congress, through Secretarial contracts authorized by the 

Boulder Canyon Project Act, allocated water from the mainstem of the Colorado River 

below Lee Ferry among California, Nevada, and Arizona, and the Gila River between 

Arizona and New Mexico. This apportionment was upheld by the Supreme Court, in 

1963, in the case of Arizona v. California. 

As confirmed by the U.S. Supreme Court in 1963, from the mainstem of the Colorado 

River (i.e., The Lower Basin): 
7 

 Nevada was apportioned 300,000 acre-feet annually and 4 percent of surplus 

water available, 

 Arizona was apportioned 2,800,000 acre-feet annually and 46 percent of surplus 

water available, 

 California was apportioned 4,400,000 acre-feet annually and 50 percent of 

surplus water available. 

Water Quality 

Although a number of water-quality-related legislative actions have been taken on the 

State and Federal levels, several Federal acts are of special significance to the Colorado 

River Basin: the Water Quality Act of 1965 and related amendments, the Federal Water 

Pollution Control Act Amendments of 1972 (Public Law 92-500), commonly referred to 

as the Clean Water Act and related amendments, and the Colorado River Basin Salinity 

Control Act (Salinity Control Act) of 1974 as amended. Also, central to water quality 

issues are agreements with Mexico on Colorado River System waters entering that 

country. 

The Water Quality Act of 1965 (Public Law 89-234) amended the Federal Water 

Pollution Control Act and established a Federal Water Pollution Control Administration 

(now Environmental Protection Agency [EPA]). Among other provisions, it required 

States to adopt water quality criteria for interstate waters inside their boundaries. The 

seven Basin States initially developed water quality standards that did not include 

numeric salinity criteria for the Colorado River primarily because of technical 

constraints. In 1972, the Basin States agreed to a policy that called for the maintenance of 

salinity concentrations in the Lower Colorado River System at or below existing levels, 

while the Upper Colorado River Basin States continued to develop their 

compact-apportioned waters. The Basin States suggested that Reclamation should have 

primary responsibility for investigating, planning, and implementing the proposed 

Salinity Control Program. 

The enactment of the Federal Water Pollution Control Act Amendments of 1972 affected 

salinity control, in that it was interpreted by EPA to require numerical standards for 

salinity in the Colorado River. In response, the Basin States founded the Colorado River 

Basin Salinity Control Forum (Forum) to develop water quality standards, including 

numeric salinity criteria and a basinwide plan of implementation for salinity control. The 

Basin States held public meetings on the proposed standards as required by the enacting 

legislation. The Forum recommended that the individual Basin States adopt the report, 

Water Quality Standards for Salinity, Including Numeric Criteria and Plan of 

Implementation for Salinity Control, Colorado River System. The proposed water quality 

standards called for maintenance of flow-weighted annual averaged total dissolved solids 

concentrations of 723 milligrams per liter (mg/L) below Hoover Dam, 747 mg/L below 

Parker Dam, and 879 mg/L at Imperial Dam. Included in the plan of implementation 

were four salinity control units and possibly additional units, the application of effluent 

limitations, industrial use of saline water, and future studies. The standards are to be 

reviewed at 3-year intervals. All of the Basin States adopted the 1975 Forumrecommended standards. EPA approved the standards. 
8 

The Salinity Control Act of 1974 (Public Law 93-320) provided the means to comply 

with the United States’ obligations to Mexico under Minute No. 242 of the International 

Boundary and Water Commission, United States and Mexico, which included, as a major 

feature, a desalting plant and brine discharge canal for treatment of Wellton-Mohawk 

Irrigation and Drainage District (WMIDD) drainage water. These facilities enable the 

United States to deliver water to Mexico having an average salinity of 115 parts per 

million (ppm) plus or minus 30 ppm (United States’ count) over the annual average 

salinity of the Colorado River at Imperial Dam. The act also authorized construction of 4 

salinity control units and the expedited planning of 12 other salinity control projects 

above Imperial Dam as part of the basinwide salinity control plan. 

In 1978, the Forum reviewed the salinity standards and recommended continuing 

construction of units identified in the 1974 act, placing of effluent limitations on 

industrial and municipal discharges, and reduction of the salt-loading effects of irrigation 

return flows. The review also called for the inclusion of water quality management plans 

to comply with section 208 of the Clean Water Act. It also contemplated the use of saline 

water for industrial purposes and future salinity control. 

Public Law 98-569, signed October 30, 1984, amended Public Law 93-320. The 

amendments to the Salinity Control Act authorized the U.S. Department of Agriculture 

(USDA) Colorado River Salinity Control Program. The amendments also authorized two 

new units for construction under the Reclamation program. 

In 1993, the Dept. of Interior Inspector General concluded that the lengthy congressional 

authorization process for Reclamation projects was impeding the implementation of costeffective measures. Consequently, a public review of the program was conducted in 

1994. In 1995, Public Law 104-20 authorized Reclamation to implement a basinwide 

approach to salinity control and to manage its implementation. Reclamation completed 

solicitations in 1996, 1997, 1998, 2001, and 2004 in which Reclamation requested 

proposals, ranking the proposals based on their cost and performance risk factors, and 

awarded funds to the highest ranked projects. The awards from the first three solicitations 

consumed the available appropriation ceiling of $75 million authorized by Congress to 

test the new program. In 2000, Public Law 106-459 amended the Colorado River Basin 

Salinity Control Act to increase the appropriation ceiling for Reclamation’s basinwide 

approach by $100 million ($175 million total). This appropriation authority allowed 

Reclamation to continue to request new proposals under its Basinwide Salinity Control 

Program. 

In 1996, Public Law 104-127 significantly changed the authorities provided to NRCS. 

Rather than carry out a separate salinity control program, the Secretary of Agriculture 

was directed to carry out salinity control measures in the Colorado River Basin as part of 

the Environmental Quality Incentives Program established under the Food Security Act 

of 1985. Public Law 104-127 also authorized the Secretary of Agriculture to cost share 

salinity control activities from the basin funds in lieu of repayment. Cost sharing has been 

implemented for both USDA and Reclamation programs. Under this new authority, each 

dollar appropriated by the Congress is matched by $0.43 in cost sharing from the basin 

funds. 
9 

In 2002, Public Law 107-171, Title II, Subtitle D reauthorized the NRCS’s 

Environmental Quality Incentives Program (under which the Secretary of Agriculture 

carries out salinity control measures). In 2008, Public Law 110-246, again authorized the 

NRCS’s Environmental Quality Incentives Program. PL110-246 also amended the 

Salinity Control Act to clarify the authority and implementation of the “Basin States 

Program”. 

Nothing in this report is intended to interpret the provisions of applicable federal law 

including, but not limited to, The Colorado River Compact (42 Stat. 171), 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), the 1964 

Decree entered by the Supreme Court of the United States in Arizona v. California et al. 

(376 U.S. 340), as amended and supplemented, 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 (70 Stat. 105; 43 U.S.C. 620), The Colorado River 

Basin Project Act (82 Stat. 885; 43 U.S.C. 1501), The Colorado River Basin Salinity 

Control Act (88 Stat. 266; 43 U.S.C. 1571), The Hoover Power Plant Act of 1984 (98 

Stat. 1333), The Colorado River Floodway Protection Act (100 Stat. 1129; 43 U.S.C. 

1600), or The Grand Canyon Protection Act of 1992 (Title XVIII of Public Law 102-575, 

106 Stat. 4669). 
10 

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11 

Sources of Salinity

Natural

47%

M&I

4%

Reservoir

12%

Irrigation

37%

CHAPTER 2 – SALINITY CONDITIONS

CAUSES OF SALINITY 

The Colorado River System is naturally very saline. Historically at the USGS gauge 

below Hoover Dam, between 1940 and 1980, an annual average of approximately 9.3 

million tons of salt was carried down the river. From 2005 to present, an annual average 

of approximately 7.7 million tons of salt are being measured in the river, including years 

of floods and drought, with the trend going down. The flow of the river dilutes this salt, 

and depending upon the quantity of flow, salinity can be relatively dilute or concentrated. 

Since climatic conditions directly affect the flow in the river, salinity in any one year may 

double (or halve) due to extremes in runoff. Because this natural variability is virtually 

uncontrollable, the seven Basin 

States adopted a non-degradation 

water quality standard. 

Nearly half of the salinity 

concentration in the Colorado 

River System is from natural 

sources. Saline springs, erosion of 

saline geologic formations, and 

runoff all contribute to this 

background salinity. Irrigation, 

reservoir evaporation, and 

municipal and industrial (M&I) 

sources make up the balance of 

the salinity problem in the 

Colorado River Basin. Figure 1 

shows the relative amount each source 

contributes to the salinity problem as 

estimated by the Environmental Protection Agency (EPA) in 1973. The EPA (EPA, 

1971) estimated that the natural salinity in the Lower Colorado River at Imperial Dam 

was 334 milligrams per liter (mg/L). At the end of 2011 the average annual flow 

weighted salinity at Imperial Dam was 680 mg/L, a 346 mg/L increase over the estimated 

natural salinity. Table 1, on the following page, quantifies the salinity from several of 

these known sources. 

Salinity of the Colorado River has increased with the development of water resources in 

two major ways: (1) the addition of salts from water use and (2) the consumption 

(depletion) of water. The combined effects of water use and consumption have had a 

significant impact on salinity in the Colorado River Basin. The basin-wide drought, since 

1999, has also had an influence on the present salinity of the Colorado River. 

Current information indicates that the present salt levels in the Colorado River system 

have few if any negative health effects and the EPA’s primary drinking water standards 

are not exceeded. However, the EPA secondary drinking water standards of 500 mg/L for 

Figure 1 
12 

Table 1 - Quantified Sources of Salt Loading

TDS (salinity) and 250 mg/L for sulfate may be exceeded. A regression of sulfate versus 

TDS shows that sulfate exceeds 250 mg/L when the TDS exceeds 612 mg/L. During dry 

cycles the secondary drinking water standards for TDS and sulfate are exceeded at many 

places in the Colorado River in both the Upper and Lower Basins, including the three 

salinity criteria sites. 

ECONOMIC EFFECTS OF SALINITY

The primary negative impact of the Colorado River salinity is economical. Reclamation 

has developed a model which calculates damages for a given level of salt (FAR, 2012). 

The Salinity Damages Model estimates the quantitative damages that are incurred in the 

metropolitan and agricultural areas in the lower Colorado Basin that receive Colorado 

River water. The model estimates the impacts from salinity levels greater than 500 mg/L 

TDS on household water using appliances, damages in the commercial sector, industrial 

sector, water utilities, and agricultural crop revenues. It also estimates the additional 

Source 

Type of 

Source 

Salt Loading 

(tons per year) 

Paradox Springs Springs / point 205,000 1 

Dotsero Springs Springs / point 182,600 

Glenwood Springs Springs / point 335,000 

Steamboat Springs Springs / point 8,500 

Pagosa Springs Springs / point 7,300 

Sinbad Valley Springs / point 6,500 

Meeker Dome Springs / point 57,000 1 

Other minor springs in the Upper Basin Springs / point 19,600 

Blue Springs Springs / point 550,000

La Verkin Springs Springs / point 109,000 

Grand Valley Irrigation / non-point 580,000 

Big Sandy Irrigation / non-point 164,000 

Uncompahgre Project Irrigation / non-point 360,000 1 

McElmo Creek Irrigation / non-point 119,000 

Price-San Rafael Irrigation / non-point 258,000 1 

Uinta Basin mostly irrigation / non-point 240,000 

Dirty Devil River Area Irrigation / non-point 150,000 

Price-San Rafael Area Irrigation / non-point 172,000 1 

Other, non regulated areas Various 5,200,000 

Total 8,724,000 

1- Values listed are pre salinity control project loading 
13 

costs related to meeting state wide water quality standards for ground water and recycled 

water use in the MWD service area. 

In FY12, presentations to the Salinity Forum, Science Team, and Work Group were made 

regarding capabilities of the Salinity Damage Model. A request to estimate the economic 

impact caused by a change in Colorado River water TDS levels if the Paradox Valley 

Unit (PVU) went offline was received and completed in FY12. The hydrologic analysis 

showed that TDS levels at Hoover, Parker, and Imperial Dams would increase by 10 

mg/L if the PVU went offline. If the PVU is online, and if no additional control 

measures are implemented over those presently employed between now and 2030, 

economic damages in the Lower Basin would be approximately $523 million annually. If 

the PVU was taken offline, the TDS levels would rise by 10 mg/L at Hoover, Parker, and 

Imperial Dams and economic damages in the Lower Basin would increase an additional 

$24 million over the $523 million by 2030. 

Two scenarios, using 2010 salinity levels, are modeled for salt damage (combining the 

impacts at Hoover, Parker and Imperial Dams) by 2030, one assumes no more salinity 

control projects built over those currently in place increasing salt damages by 

$228,000,000. The second scenario assumes the salinity control program is fully 

implemented and a total salt damage of $111,000,000 over present levels. Even though 

the salinity level has fluctuated slightly over the last few years, the salinity impact cost 

has increased primarily due to increased agricultural damage costs (increase in acreage 

and crop prices). 

Salinity related damages are 

primarily due to reduced agricultural 

crop yields, corrosion, and plugging 

of pipes and water fixtures in 

housing and industry. Figure 2 

breaks down the percentage of total 

damages. The seven Basin States 

have agreed to limit this impact and 

adopted numeric criteria, which 

require that salinity concentrations 

not increase (from the 1972 levels) 

due to future water development. 

Salinity levels measured in the river 

may be low or high due to climatic 

conditions, but the goal of the Water Quality Criteria for the Colorado River Basin and 

the Colorado River Basin Salinity Control Program (Salinity Control Program) is to 

offset (eliminate/reduce) the salinity effects of additional water development. 

HISTORIC SALINITY CONDITIONS 

Salinity in the Colorado River is monitored at 20 key stations throughout the Colorado 

River Basin, Appendix A. Salt loads and concentrations are calculated from daily 

conductivity and flow records using methods developed jointly between Reclamation and 

 Figure 2 – Percentage of Salinity Damages
14 

USGS (Liebermann et al., 1986), Appendix B. Historical annual streamflow, and salinity 

concentrations from 1940 through 2011 are included in graphical form in Appendix C. 

Monthly and annual data may be obtained by request from Reclamation, Salt Lake City, 

Utah or by going to Reclamation’s Upper Colorado Regional Office Salinity Program 

web page; http://www.usbr.gov/uc/progact/salinity/index.html. 

The salinity of the 3 lower basin compact points since 1940 is shown in Figure 3. As 

Figure 3 shows, the last time the TDS exceeded or reached the salinity criteria at any of 

the compact points, was in 1972 – the year that the salinity standard was established for 

the Colorado River. 

Figure 3 - Colorado River Salinity at Lower Basin Compact Points

FACTORS INFLUENCING SALINITY 

Stream flow, reservoir storage, water resource development, salinity control, climatic 

conditions, and natural runoff directly influence salinity in the Colorado River Basin. 

Before any water development, the salinity of spring runoff was often below 200 mg/L 

throughout the Colorado River Basin. However, salinity in the lower mainstem was often 

well above 1,000 mg/L during the low flow months (most of the year), since no 

reservoirs existed to catch and store the spring runoff. 

Streamflow 

Streamflow directly influences salinity. For the most part, higher flows (or reservoir 

releases) dilute salinity. The top graph in Figure 4 shows streamflow at two key points
15 

in the mainstem. In 1983, Lake Powell (Glen 

Canyon Dam) filled for the first time and 

spilled. 

This spill went through Lake Mead (Hoover 

Dam) and on downstream through Imperial 

Dam. In 1983 and on through 1987, flows in 

the system were again extremely high and 

sustained, reducing salinity to historic lows. 

As shown in the bottom graph of Figure 4, 

returning to average flows in the system 

after1987 returned the salinity in the 

reservoir system to average levels. 

Reservoir Storage 

The Colorado River Storage Project 

Reservoirs produce not only major 

hydrologic modifications downstream, but 

they also significantly alter the salinity 

variability of the downstream river. The 

overall long term salinity effects of the 

reservoirs are beneficial and have greatly 

reduced the salinity peaks and annual 

fluctuation (Figure 5). The high concentration low flow waters are mixed with low 

concentration spring runoff, reducing the month-to-month variation in salinity below 

dams (Mueller et al., 1988). At Glen Canyon Dam, the pre and post dam peak monthly 

salinity has been reduced by nearly 600 mg/L. Similar effects can be seen below Flaming 

Gorge, Navajo, and Hoover Dams, greatly improving the quality of water during the 

summer, fall and winter. 

Large reservoirs like Lake Powell selectively route less saline water while holding more 

saline waters during low inflow periods. The poorer quality waters are then slowly 

released after the inflows have begun to increase, which helps to prevent exceeding the 

salinity criteria during drought years. The large reservoirs selectively retain higher 

salinity winter inflows in the bottom of the pool and route lower salinity overflow density 

currents from the spring runoff. The seasonal and long term affects of this selective 

retention and routing of salt has been shown below Glen Canyon Dam in Figure 5. 

Figure 6 further displays this retention. Figure 6 is a long-term depth vs. time profile of 

salinity in the forebay of Glen Canyon Dam and is an illustrated history of the salinity. 

The Y (vertical) axis is depth in the water column and the X axis is time in years. The 

color scale is the change in salinity. 

Figures 6 and 7 illustrate that Glen Canyon Dam causes Lake Powell to selectively retain 

higher salinity water during drier years of drought, and then routes it out with the 

increased mixing and shorter hydraulic retention times of wetter cycles as seen 

particularly in 1983 and 1999. During these wetter cycles there is a significant mixing 

and dilution of these previously stored salts. 

Figure 4 - Mainstem Flow and Salinity. 
16 

0

200

400

600

800

1000

1200

1400

1600

1940 1950 1960 1970 1980 1990 2000 2010

Monthly Salinity (mg/L)

Salinity Below Glen Canyon Dam 

Dam closure and 

reservoir storage in 

mid-1960's reduced 

variation in salinity

1964

Figure 5 - Effects of Glen Canyon Dam on Colorado River Salinity at Lees Ferry.

Figure 6 - Lake Powell Forebay, near Dam, Dec 1964 to Dec 2012 Salinity Concentration, mg/L 
17 

300

400

500

600

700

800

900

1000

1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

Average Annual TDS (mg/L)

Inflow TDS 1940 to 2011

Outflow TDS 1940 to 2011

Linear (Inflow TDS 1940-1964, 1964-1983, 1983-2000, 2000-2011)

Linear (Outflow TDS 1940-1964, 1964-1983, 1983-2000, 2000-2011)

Linear (Inflow TDS 1964 to 2011)

Linear (Outflow TDS 1964 to 2011)

Figure 7 - Lake Powell Inflow and Outflow Salt Concentration, mg/L

There are 4 periods or trends which can be seen in the Colorado River salinity for the 

inflow to and outflow from Lake Powell which can be seen in Figure 7 (yellow and white 

trend lines). The overall inflow line (blue) in Figure 7 is the sum of TDS for the inflow 

stations to Lake Powell; Colorado River at Cisco, Green River at Green River, UT, San 

Rafael River near Green River and San Juan River near Bluff. The overall outflow line 

(red) is the TDS at the USGS gauge at Lees Ferry below Glen Canyon Dam. During the 

pre dam period, 1940 – 1964, the average salinity trend was increasing with divergence 

between the average annual inflow and outflow salinity levels and the inflow 

concentration generally being less than the outflow concentration. This difference 

between outflow and inflow may be impacted by the beginning hydraulic conditions, 

since the actual annual levels appear to track each other fairly closely. Next there was the 

dam filling period where Lake Powell and the Upper Basin reservoirs were completed 

and filling, 1965-1983. The average annual salinity during this time decreased with a 

convergence occurring between the inflow and outflow concentrations. The outflow 

concentration decreased more than the inflow concentration, which could be due to the 

reservoir storing the higher TDS waters. Then there was the period, 1983 to 2000, when 

the basin hydrology went through both wet and dry periods and the salinity control 

projects in the upper basin were coming online. The declining trend of the average 

annual salinity concentration over this time is seen to be constant between the inflow and 

outflow stations. Since 1980 there appears to be an equilibrium between the salt entering 

the reservoir and what is being released. The last period, since 2000, covers the 

basinwide drought. The trend shows that the inflow TDS has declined, while the outflow 

TDS from Lake Powell has stayed constant with the 1980 to present TDS trend. 

Lake Powell (and other reservoirs in the basin) went through an initial filling salt leach 

out which actually began with temporary water retention behind the coffer dam during 

construction in the mid 1950’s. Long-term linear regression trend lines on the inflow and 
18 

outflow salinity concentrations at Lake Powell indicate that internal salt leaching seems 

to have declined to a minimum by the mid-1990’s suggesting a long-term salinity leach 

out which is approaching a dynamic equilibrium (Figure 7, red and blue dotted trend 

line). 

 

NATURAL VARIATION IN SALINITY 

Although seasonal swings in salinity have been greatly reduced, annual fluctuations in 

salinity are still observed. Natural climatic variations in rainfall and snowmelt runoff 

continue to cause large year-to-year differences in both flow and salinity and in some 

cases nearly doubling the salinity in the river. 

The water quality standards require that the flow-weighted average annual salinity not to 

rise above the 1972 levels using a long-term mean water supply of 15 maf (2011 

Review). This means that depending on the hydrology (drought conditions) salinities may 

actually increase above the numeric criteria and it is not a violation of the standards, but 

is due to natural variations in the hydrologic conditions. Even with full compliance with 

the standards, the actual salinities at Imperial Dam (and elsewhere in the Colorado River 

Basin) will continue to fluctuate with hydrologic conditions in the future. The Salinity 

Control Program is designed to offset the effects of development, even as salinity varies 

from year to year in response to the climatic and hydrologic conditions. Assuming 

continued salinity control and full compliance with the standards, the potential range of 

annual salinities that might be observed in the future at Imperial Dam is quite wide. With 

Colorado River basin reservoir storage tempering the natural variability of the system, the 

range between the high and low salinity values at Imperial Dam has dropped to a monthly 

average of about 479 mg/L and an annual average around 266 mg/L since 1973. 

AGRICULTURAL SOURCES OF SALINITY 

Irrigated agriculture is the largest user of water in the Colorado River Basin and a major 

contributor to the salinity of the system. Iorns (Iorns et al., 1965) found that irrigated 

lands in the Upper Colorado River Basin contributed about 3.4 million tons of salt per 

year (37 percent of the salinity of the river). Irrigation increases the salt concentration of 

the source water by consuming water (evapotranspiration) and by dissolving salts found 

in the underlying saline soil and geologic formations, usually marine (Mancos) shale. 

Irrigation mobilizes the salts found naturally on the soil surface as well as in the soil 

profile, especially if the lands are over irrigated. Many subbasins experienced significant 

changes in irrigation following development of available reservoir storage. For example, 

once late season irrigation supplies were assured, less water was applied to per unit of 

farmland during the snowmelt runoff, and overall irrigation efficiency increased. 

Irrigation development in the Upper Colorado River Basin took place gradually from the 

beginning of settlement in about 1860, but was hastened by the purchase of tribal lands in 

the late 1800’s and early 1900’s. About 800,000 acres were being irrigated by 1905. 

Between 1905 and 1920, the development of irrigated land increased at a rapid rate, and 

by 1920, nearly 1.4 million acres were being irrigated. The “Upper Colorado Region 
19 

Comprehensive Framework Study, June 1971”, reported that more than 1.6 million acres 

were in irrigation in 1965. Since that time, development of new agricultural lands has 

leveled off because of physical, environmental, and economic limitations. Reclamation’s 

latest “Colorado River System Consumptive Uses and Losses Report 2006-2010” 

estimated an average of 1.7 million acres was irrigated in the Upper Colorado River 

Basin in 2010 (latest data available). 

Irrigation development in the Lower Colorado River Basin began at about the same time 

as in the Upper Colorado River Basin, but was slow due to the difficulty of diverting 

water from the Colorado River with its widely fluctuating flows. Development of the Gila 

area began in 1875 and the Palo Verde area in 1879. Construction of the Boulder Canyon 

Project in the 1930’s, and other downstream projects, has provided for a continued 

expansion of the irrigated area. In 1970, an additional 21,800 acres were irrigated by 

private pumping either directly from the Colorado River or from wells in the flood plain. 

In 1980, nearly 400,000 acres were being irrigated along the Colorado River mainstem. 

Total irrigated lands within the Lower Colorado River Basin using Colorado River water 

is estimated at over 1 million acres. 

Reclamation and the U.S. Geological Survey (USGS) continuously monitor the flow and 

salinity of the river system through a network of 20 gauging stations (See Appendix A, 

Figs. A1 & A2; Appendix C Figs. C1 – C5). Reclamation evaluates the data collected to 

determine if sufficient salinity control is in place to offset the impact of water 

development. In 2011, the actual salinity in the Colorado River was below the numeric 

criteria at the established monitoring stations. However, as the impacts of recent and 

future basin developments work their way through the hydrologic system, or as drought 

conditions persist, salinity would increase without salinity control to prevent further 

degradation of the river system. Through salinity control practices, excess salt loading to 

the river system can be reduced significantly, helping maximize the future beneficial uses 

of the river. 

Most of the irrigation projects that deplete water and increase salt loading to the river 

were in place before 1965. Moreover, like the newly inundated soils in reservoirs, newly 

irrigated lands are subject to a leach-out period. In cases where lands with poor drainage 

stored salt, these areas were taken out of production. In addition, irrigation practices 

changed significantly with the introduction of canal and lateral lining, sprinkling systems, 

gated pipe, trickle systems and tile drains (initial operation of tile drains increase salt 

loading, which decreases after time). These changes have resulted in reduced return flows 

and salt loading. 

WATER USE BY MUNICIPAL & INDUSTRIAL USERS 

Salinity levels are directly influenced by depletion (consumption) of water flowing in the 

river system and salt loading. Agriculture increases salinity by consuming water through 

evapotranspiration and leaching of salts from soils by irrigation. Municipal and industrial 

(M&I) use increases salinity by the consumption of the water, thus reducing the dilution 

of salts in the river or by disposal on land. 
20 

Another source of salinity from municipal & industrial use is from an increase in the 

housing developments within the basin. This brings with it an associated increase in 

water softening needs, due to the hard water found throughout the basin. One result of the 

increase of water softening is an increase in the sodium chloride salt discharged into the 

Colorado River. Another impact of the increased population in the basin is that more 

roads are paved and developed. During the winter this increase in road mileage impacts 

the salt discharged into the basin due to the addition of salt on the roads in order to help 

keep the snow and ice off of the roads. The amount of salt added to the basin from new 

municipal development has not yet been quantified. 

Reclamation continues to monitor water use and adjust future salinity control needs as 

water development plans may be postponed, delayed, or canceled. The depletion 

schedules used to project salinity conditions have been updated with multiple demand 

projection scenarios, so that the implementation needs for the Salinity Control Program 

can be planned to offset the potential impacts of additional water development (see 

Tables 2 & 3). 

ENERGY DEVELOPMENT 

The large amounts of water use once forecasted for steam power generation, coal 

gasification, oil shale, and mineral development have not yet occurred. The few 

coal-fired power plants that have been constructed recently have obtained their water 

from existing agricultural rights rather than from developing additional water. This 

conversion of use reduces the salt loading to the Colorado River by eliminating the 

pickup of salt from canal seepage and on farm deep percolation. 

Many of the geologic formations of the Colorado River Basin were deposited in marine 

(saline) or brackish water environments. Sulfates and sodium chloride are prevalent salts 

in most of these formations. Many of the formations were deposited in drier periods and 

are capable of transmitting water, but these aquifers are frequently sandwiched between 

hundreds or even thousands of feet of impermeable shale (aquicludes). These aquifers 

are, therefore, static and often saline. Many static and saline aquifers are present in the 

Colorado River Basin. When a path of flow is provided by drilling or mining, these 

aquifers are mobilized, and brackish or saline waters flow back to the surface. 

The development of energy resources, specifically coal, oil, gas, oil shale, and coal bed 

methane, in the Colorado River Basin may contribute significant quantities of salt to the 

Colorado River. Salinity of surface waters can be increased by either mineral dissolution 

or uptake in surface runoff, mobilization of brackish groundwater, or consumption of 

good quality water. The location of this energy development is associated with marinederived formations. Any disturbance of these saline materials will increase the contact 

surfaces, allowing for the dissolution of previously unavailable soluble minerals. 

Salinity increases associated with mining coal can be attributed to leaching of coal spoil 

materials, discharge of saline groundwater, and increased erosion resulting from surfacedisturbing activities. Spoil materials have a greater permeability than undisturbed 

overburden, allowing most of the rain falling on the spoils to infiltrate instead of running 

off. The water percolates through the spoils, dissolving soluble minerals. 

Studies conducted on mining spoils in northwestern Colorado indicate that the resulting 
21 

salinity of spoil-derived waters ranges from approximately 3,000 mg/L to 3,900 mg/L 

(Parker, et al., 1983; McWhorter, et al., 1979; and U.S. Department of the Interior, 1985). 

The variability in concentration depends on water residence time and the chemical and 

physical properties of the spoil. 

Saline water is also a byproduct of oil and gas production in the Colorado River Basin. It 

is not uncommon to produce several times the amount of saline waters as oil. In one 

month the oil and gas operators in Colorado produced approximately 25 million barrels 

of saline water. The salinity of production waters varies greatly from location to location 

and depends upon the producing formation. Common disposal techniques include 

evaporation, injection, and discharge to local drainages. 

The future development of the oil shale resources in Colorado, Utah, and Wyoming has 

the potential to increase salt loading to the Colorado River. Salt increases can be 

attributed to the consumptive use of good quality water, mine dewatering, and, if surface 

retorting is used, the leaching of spoil materials similar to those of surface coal mining. 

Reclamation, BLM and state agencies are attempting to identify abandoned exploration 

wells that are leaking and develop plans to control the leaks. The Meeker Dome Salinity 

Control Unit identified and plugged several abandoned wells along the White River to 

prevent a salt dome (a geologic formation) from discharging saline water into the river. 

Oil and Natural Gas – Recent 

technological advances in well 

drilling have allowed for more 

efficient extraction of oil and gas 

from the formations in which they 

are found, especially shale 

formations. This has led to an 

increase in the number of natural 

gas and oil wells developed in the 

Upper Colorado River Basin. The 

natural gas wells also include coal 

bed methane wells. This increase 

in energy development and 

associated well drilling could result 

in an increase in the salt loading of the Colorado River if the drilling waste water is 

discharged on the ground surface and allowed to get into waterways, however most of 

this saline water is either reinjected or captured in evaporation ponds. 

In Utah, oil and gas wells are primarily located in Emery, Carbon, Duchesne, and Uinta 

counties. The State allows up to 4 wells per section. Most (99%) of existing product 

wastewater from the wells is reinjected and 1 % is impounded for evaporation. No 

surface discharges have presently been permitted. It is projected that even with greater 

development of oil and gas wells, the handling of the produced wastewater will not 

change. 

In Colorado, all the product water from oil and gas development in the San Juan Basin in 

southwest Colorado is presently, and in the foreseeable future will be, reinjected. New 

wells are permitted in the northwest part of the State and in Moffat and Rio Blanco 

Figure 8 - Photo of natural gas well. 
22 

Counties, where new energy developments are being considered. The State averages for 

product wastewater in the western part of the State are 90 % reinjected, 9.5 % 

impounded, and 0.5 % surface discharged. Any surface discharged water has to meet the 

water quality criteria of no more that 1 ton/day salt. 

In Wyoming, new oil and gas well development is beginning in the Little Snake River 

drainage (Carbon County) with only a handful of wells permitted. This energy 

development has the potential to spread into the whole southwest corner of the State 

(Sweetwater, Uinta, and Lincoln Counties). Presently, the State will allow surface 

discharge of up to 1 ton/day per operator (not per well). Oil and gas development in the 

southwest part of the State will most likely involve reinjection of most if not all of the 

waste water since the quality of the groundwater found in the geologic formations is 

highly saline and of poor quality. 

FUTURE WATER DEVELOPMENT 

Tables 2 and 3 summarize the projected demand scenarios used by Reclamation to 

evaluate the effects of water use and depletions in the recently completed Colorado River 

Basin Study (Reclamation, 2012a). These water demand estimates were compiled as an 

initial step in the evaluation process. 

Table 2 summarizes the projected demand by water uses in the Upper Colorado River 

Basin as adopted for planning purposes in the Colorado River Basin Water Supply and 

Demand Study, Technical Report C – Water Demand Assessment December 2012. 

Figure 9 illustrates the historic annual consumptive use by water uses in the Upper Basin 

as reported in Reclamation’s Colorado River System Consumptive Uses and Losses 

Reports (CUL), and the total projected demands by water uses in the Upper Basin that are 

included as input into Reclamation’s Colorado River System Simulation (CRSS) model. 

The consumptive uses and projected demands shown in Figure 9 exclude evaporation 

losses from Lake Powell, Flaming Gorge Reservoir and the Aspinall Unit reservoirs, 

which along with evaporation losses from Colorado River mainstem reservoirs in the 

Lower Basin are modeled within CRSS. 

The annual depletions for the Lower Colorado River Basin shown in Table 3 include only 

depletions resulting from the use of water from the mainstem of the Lower Colorado 

River. Reclamation’s CRSS model does not model or include as input consumptive uses 

made from tributaries to the Colorado River within the Lower Colorado River Basin. 

Fixed inflow values are used in the CRSS model for the Lower Basin tributaries. More 

detailed data on historic Colorado River Basin consumptive uses and losses (including 

tributary uses in the Lower Basin and reservoir evaporation losses) may be found in 

Reclamation’s Colorado River System Consumptive Uses and Losses Reports or on the 

web at: www.usbr.gov/uc/library/envdocs/reports/crs/crsul.html
23 

Table 2 - Upper Basin Total Projected Depletion Demand Scenarios (1000 af/yr) 

UPPER BASIN 20151 20351 20601 20152 20352 20602 20153 20353 20603

 

Arizona 

Agricultural 0 0 0 0 0 0 0 0 0

Municipal and Industrial 2 2222 2 2 2 2

Energy 0 0 0 0 0 0 0 0 0

Minerals 0 0 0 0 0 0 0 0 0

Fish, Wildlife and Recreation 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3

Tribal 44 43 43 38 55 71 44 43 43

Total Potential Colorado River Demand 46 46 46 40 57 73 46 46 46

Colorado

Agricultural 1,875 1,875 1,875 1,875 1,791 1,728 1,875 1,875 1875

Municipal and Industrial 455 617 732 455 579 1,007 455 555 661

Energy 30 78 118 30 65 66 30 51 58

Minerals 32 59 60 32 65 66 31 59 60

Fish, Wildlife and Recreation 0 0000 0 0 0 0

Tribal 0 0 0 0 0 0 0 0 0

Total Potential Colorado River Demand 2,391 2,629 2,784 2,391 2,535 2,979 2,391 2,540 2,653

New Mexico

Agricultural 111 111 111 111 111 111 111 111 111

Municipal and Industrial 141 183 230 141 187 293 141 153 169

Energy 40 42 42 40 42 42 40 42 42

Minerals 0 0 0 0 0 0 0 0 0

Fish, Wildlife and Recreation 5 5555 5 5 5 5

Tribal 303 363 367 309 413 529 303 363 367

Total Potential Colorado River Demand 600 703 754 606 758 979 600 673 693

Utah

Agricultural 457 459 493 457 446 466 457 458 492

Municipal and Industrial 236 311 342 236 341 409 236 280 274

Energy 47 53 60 47 55 66 47 53 60

Minerals 0 0 0 0 0 0 0 0 0

Fish, Wildlife and Recreation 0 0000 0 0 0 0

Tribal 259 259 259 272 299 337 170 241 259

Total Potential Colorado River Demand 999 1,082 1,154 1,012 1,141 1,277 911 1,033 1,084

Wyoming

Agricultural 398 402 406 400 410 423 400 410 423

Municipal and Industrial 30 47 67 30 57 74 28 32 36

Energy 52 65 65 52 103 171 52 65 65

Minerals 29 42 59 34 57 91 29 42 59

Fish, Wildlife and Recreation 2 10 10 2 10 10 2 10 10

Tribal 0 0 0 0 0 0 0 0 0

Total Potential Colorado River Demand 511 566 606 518 637 769 512 559 592

Note 1: These demand scenarios do not attempt to interpret the Colorado River Compact, the Upper Colorado River 

Basin Compact, or any other element of the “Law of the River.” These scenarios should not be construed as an 

acceptance of any assumption that limits the Upper Colorado River Basin’s depletion. 

Note 2: These demand scenarios are for planning purposes only. Their estimates do not constitute an endorsement of 

the Bureau of Reclamation’s 2007 Hydrologic Determination and should not be construed as in any way limiting the 

Upper Division States use of Colorado River water in accordance with the Commission’s resolution of 6/5/06. 

Note 3: These demand scenarios exclude shared CRSP evaporation. 

Option 1 . Scenario A; (Current projected use), continuation of growth, development patterns, and institutions follow 

long-term trends. Colorado River Basin Water Supply and Demand Study. Technical Report C – Water Demand 

Assessment. 

Option 2 . Scenario C1; (Rapid Growth) Economic resurgence (population and energy) and current preferences 

toward human and environmental values (greatest water demand model). Colorado River Basin Water Supply and 

Demand Study. Technical Report C – Water Demand Assessment.

Option 3 . Scenario B; (Slow Growth) Slow growth with emphasis on economic efficiency (lowest water demand 

model). Colorado River Basin Water Supply and Demand Study. Technical Report C – Water Demand Assessment
24 

Table 3 - Lower Basin Depletion Projections (1000 af/yr) 

LOWER MAINSTEM 20151 20351 20601 20152 20352 20602 20153 20353 20603

 

Arizona 

 

Agricultural 1,124 703 703 1.082 703 703 1,145 724 724

Municipal and Industrial 760 1,099 1,460 816 1,305 2,060 823 1,075 1,164

Energy 1 1 2 1 2 2 1 1 2

Minerals 42 54 55 42 53 54 42 60 60

Fish, Wildlife and Recreation 16 16 16 16 16 16 16 16 16

Tribal 997 1,216 1,215 1,013 1,288 1,337 881 1,100 1,100

Total Potential Colorado River Demand 2,940 3,088 3,447 2,967 3,364 4,170 2,906 2,975 3,064

 

California 

 

Agricultural 3,230 3,103 3,159 3,230 3,103 3,159 3,229 3,103 3,158

Municipal and Industrial 1,433 1,589 1,690 1,433 1,591 1,695 1,431 1,581 1,669

Energy 53 108 156 61 171 284 53 108 156

Minerals 0 0 0 0 0 0 0 0 0

Fish, Wildlife and Recreation 124 24 32 124 24 32 124 24 32

Tribal 92 92 92 92 92 92 92 92 92

Other 48 58 75 48 58 75 48 58 75

Total Potential Colorado River Demand 4,979 4,974 5,203 4,987 5,039 5,336 4,977 4,966 5,182

 

Nevada 

 

Agricultural 0 0 0 0 0 0 0 0 0

Municipal and Industrial 289 374 506 289 416 589 289 346 479

Energy 0 0 0 0 0 0 0 0 0

Minerals 0 0 0 0 0 0 0 0 0

Fish, Wildlife and Recreation 2 2 2 2 2 2 2 2 2

Tribal 9 9 9 9 9 9 9 9 9

Total Potential Colorado River Demand 300 385 517 300 427 600 300 357 490

Note: In the LC Basin, demands are from mainstem diversions of the Colorado River only. Does not include demands 

from diversions of Colorado River tributaries or evaporation from mainstem reservoirs. 

Option 1 . Scenario A; (Current projected use), continuation of growth, development patterns, and institutions follow 

long-term trends. Colorado River Basin Water Supply and Demand Study. Technical Report C – Water Demand 

Assessment. 

Option 2 . Scenario C1; (Rapid Growth) Economic resurgence (population and energy) and current preferences toward 

human and environmental values (greatest water demand model). Colorado River Basin Water Supply and Demand 

Study. Technical Report C – Water Demand Assessment.

Option 3 . Scenario B; (Slow Growth) Slow growth with emphasis on economic efficiency (lowest water demand model). 

Colorado River Basin Water Supply and Demand Study. Technical Report C – Water Demand Assessment.
25 

 Figure 9 – Historical Water Use and Projected Water Demand. 

COMPLIANCE WITH THE SALINITY STANDARDS 

Reclamation and the Basin States conducted salt-routing studies for the 2011 Triennial 

Review of the Water Quality Standards for Salinity, Colorado River Basin. As part of the 

triennial review process, Reclamation used the Colorado River Simulation System 

(CRSS) river system model to evaluate whether sufficient salinity control measures are in 

place to offset the effects of development. The information provided in the next two 

sections of the report was used to evaluate compliance with the water quality standards. 

In response to the Clean Water Act, the States have adopted water quality (salinity) 

criteria for the Colorado River Basin and the Environmental Protection Agency (EPA) 

has approved them at all three locations in the Lower Colorado River Basin. The 

standards call for maintenance of flow-weighted average annual salinity concentrations 

(numeric criteria) in the lower mainstem of the Colorado River and a plan of 

implementation for future controls. 

The water quality standards are based on the Water Quality Standards for Salinity, 

Including Numeric Criteria and Plan of Implementation for Salinity Control, Colorado 

River System, prepared by the Colorado River Basin Salinity Control Forum, June 1975. 

The document was adopted by each of the Basin States and approved by EPA. A 

summary of the report follows: 

The numeric criteria for the Colorado River System are to be established at levels 

corresponding to the flow-weighted average annual concentrations in the lower 

mainstem during calendar year 1972. The flow-weighted average annual salinity 

for the year 1972 was used. Reclamation determined these values from daily flow 

and salinity data collected by the USGS and the Bureau of Reclamation. Based on 
26 

this analysis, the numeric criteria are 723 mg/L below Hoover Dam, 747 mg/L 

below Parker Dam, and 879 mg/L at Imperial Dam. 

It should be recognized that the river system is subject to highly variable annual 

flow. The frequency, duration, and availability of carryover storage greatly affect 

the salinity of the lower mainstem; and, therefore, it is probable that salinity levels 

will exceed the numeric criteria in some years and be well below the criteria in 

others. However, under the above assumptions, the average salinity will be 

maintained at or below 1972 levels. 

Periodic increases above the criteria as a result of reservoir conditions or periods 

of below normal long-time average annual flow also will be in conformance with 

the standards. With satisfactory reservoir conditions and when river flows return 

to the long-time average annual flow or above, concentrations are expected to be 

at or below the criteria level. 

The standards provide for temporary increases above the 1972 levels if control 

measures are included in the plan. Should water development projects be 

completed before control measures, temporary increases above the criteria could 

result and these will be in conformance with the standard. With completion of 

control projects, those now in the plan or those to be added subsequently, salinity 

would return to or below the criteria level. 

The goal of the Salinity Control Program is to maintain the flow-weighted 

average annual salinity at or below the numeric criteria of the salinity standards. 

The program is not, however, intended to counteract the salinity fluctuations that 

are a result of the highly variable flows caused by climatic conditions, 

precipitation, snowmelt, and other natural factors. 

SALINITY CONTROL 

Existing salinity control measures prevent over a million tons of salt per year from 

reaching the river. In 2012 the salinity control program for Reclamation has controlled 

approximately 569,000 tons of salt, while the USDA NRCS (NRCS) program has 

reduced around 600,000 tons of salt, and the BLM has controlled an estimated 126,000 

tons of salt per year from entering the Colorado River (Figure 10). Discussions within 

the Colorado River Salinity Control Forum have determined that salinity control units 

will need to prevent nearly 1.85 million tons of salt per year from entering the Colorado 

River by 2030, in order to meet the standard and keep the economic damages minimized. 

To reach this objective, as shown in Table 4, the program needs to implement 555,000 

tons of new controls beyond the existing 1,295,000 tons of salinity control presently in 

place (2012) as reported by Reclamation, USDA & BLM. About 31,000 tons per year of 

new salinity control measures must be added each year if the program is to meet the 

cumulative target of 1,850,000 tons per year by 2030. 

To achieve this goal, a variety of salinity control methods are being investigated and 

constructed. Saline springs and seeps may be collected for disposal by evaporation, 

industrial use, or deep-well injection. Other methods include both on-farm and off-farm 
27 

 Figure 10 – 2012 Est. Salinity Control Progress; BOR, NRCS & BLM 

delivery system and irrigation improvements, which reduce the loss of water and reduce 

salt pickup by improving irrigation practices and by lining canals, laterals, and ditches. 

 

Table 4 - Salinity Control Requirements and Needs Through 2030 

Salinity control needs (2030) 1,850,000 tons 

Measures in place (2012) - 1,295,000 tons 

Plan of Implementation Target 555,000 tons 

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

Tons of Salt Removed

Colorado River Basin Salinity Control Program

BLM USDA BOR
28 

Page Intentionally Left Blank
29 

CHAPTER 3 – TITLE I SALINITY CONTROL PROGRAM 

The Colorado River Basin Salinity Control Act (Salinity Control Act), Public Law 

93-320, as amended, authorized the Secretary of the Interior (Secretary) to proceed with a 

program of works of improvement for the enhancement and protection of the quality of 

water available in the Colorado River for use in the United States and the Republic of 

Mexico. Title I enables the United States to comply with its obligation under the 

agreement with Mexico of August 30, 1973 (Minute No. 242 of the International 

Boundary and Water Commission, United States and Mexico [Minute No. 242]), which 

was concluded pursuant to the Treaty of February 3, 1944 (TS 994). 

Figure 11 - Map of Title I Projects. 

These facilities enable the United States to deliver water to Mexico with an average 

annual salinity concentration no greater than 115 parts per million (ppm) plus or minus 

30 ppm (United States count) over the average annual salinity concentration of the 

Colorado River water at Imperial Dam. 

The background and history of the Title I projects (Coachella Canal Lining, Protective 

and Regulatory pumping, Yuma Desalting Plant, Wellton-Mohawk Irrigation & Drainage 

District) can be found in Progress Report 22, chapter 4 at; 

http://www.usbr.gov/uc/progact/salinity/pdfs/PR22.pdf

Updates for the Title I projects since Progress Report 23 are as follows: 
30 

Coachella Canal Lining 

No new activity or change since last progress report. 

Protective and Regulatory Pumping 

No new activity or change since last progress report. 

Yuma Desalting Plant 

No new activity or change has occurred since the last progress report. 

Wellton-Mohawk Irrigation and Drainage District (WMIDD) 

Total crop acres have remained relatively stable since the early 1970’s because more 

acreage is double-cropped than when the program was initiated. In particular, more 

vegetable crops are being grown in the district than in the past. Irrigation efficiency 

levels and return flow levels for 1990-2011 are shown on the following page, in Table 5. 

With the use of monthly groundwater table monitoring using observation well 

measurements as well as input from land users, WMIDD is able to maintain a drainagepumping program that sufficiently maintains the agriculture root zone. Land users 

continue to maintain water efficient farming techniques with the use of dead level, high 

heads, and short runs. 

Table 5 - WMIDD Irrigation Efficiency 

Year 

Pumped 

Drainage 

Return Flow 

(acre-feet) 

Irrigation Efficiency, % 

(note: data provided by 

WMIDD) 

1990 

1991 

1992 

1993 

1994 

1995 

1996 

1997 

1998 

1999 

2000 

2001 

2002 

2003 

2004 

2005 

2006 

2007 

2008 

2009 

2010 

2011 

138,200 

144,900 

116,200 

 8,970 

 49,820 

121,500 

119,600 

 91,695 

 98,972 

 94,869 

110,287 

107,908 

119,410 

116,477 

106,002 

110,770 

103,810 

112,910 

120,190 

105,482 

111,170 

 108,140 

- 

68.8 

70.4 

68.8 

65.4 

64.3 

60.4 

62.2 

61.9 

63.0 

59.7 

60.9 

61.2 

57.8 

63.3 

64.6 

62.3 

62.6 

63.0 

62.7 

66.1 

64.9 
31 

CHAPTER 4 - TITLE II SALINITY CONTROL PROGRAM

Title II of the Salinity Control Act authorizes the Secretary of the Interior (Secretary) and 

the Secretary of Agriculture to implement a broad range of specific and general salinity 

control measures in an ongoing effort to prevent further degradation of water quality in 

the United States. These efforts are shown on the map below. The NRCS, BOR and 

BLM have a combined goal of controlling 1.85M tons of salt/per year, by the year 2030. 

These federal agencies are required to work together under, Public Law 93-320, 

“Colorado River Basin Salinity Control Act,” as amended; with the Bureau of 

Reclamation being the lead federal agency. The Act also calls for periodic reports on this 

effort. The report is to include the effectiveness of the units, anticipated work to be 

accomplished to meet the objectives of Title II with emphasis on the needs during the 5 

years immediately following the date of each report, and any special problems that may 

be impeding an effective salinity control program. Title II also provides that this report 

may be included in the biennial Quality of Water Colorado River Basin, Progress Report. 

New activities since the last progress report as well as ongoing and active projects are 

listed in this report. 

Las Vegas Wash 

Paria

Big Sandy

Blacks Fork

Manila

Uinta Meeker Dome 

Grand Valley

Silt

Lower Gunnison 

Paradox

Muddy Creek 

Price - San Rafael Green River

McElmo 

Mancos

San Juan 

Figure 12 – Map of Title II Salinity Control Project Areas. 
32 

U.S. Bureau of Land Management 

The BLM administers about 53 million acres of public lands in the Colorado River Basin 

above Yuma, Arizona. Substantial portions of these public lands are ecologically 

classified as arid or semiarid rangelands. Point sources of salt on public lands include 

saline springs, seeps from marine sedimentary formations, abandoned flowing wells, 

discharge from abandoned mines, and discharge of waters from authorized activities such 

as oil and gas production or mining. Nonpoint sources of salt include surface runoff, soil 

erosion, stream sediments, and groundwater discharge to streams. Salts can be 

transported either in solution or with solids such as soils or coarse fragments. Past 

studies have indicated that salt loading in rangelands is closely associated with sediment 

loading. 

Salt concentrations on public lands tend to be highest in areas underlain by marine 

sedimentary rocks such as shales and mudstones that receive less than 8 inches of annual 

precipitation. Although salt concentrations can be very high in runoff from these lands, 

the frequency and volume of runoff is low because of the low precipitation and 

ephemeral nature of stream systems. Runoff from areas with highly saline soils in the 

Upper Basin is estimated to contribute about one-third of the annual salt load from BLM 

public lands. 

The greatest volume of salt contributed from BLM-administered lands, however, is 

sourced from areas with moderate to low salt concentrations in soils that are relatively 

well-covered with perennial vegetation and receive more than 12 inches of annual 

precipitation. Although salt concentrations in runoff from these lands are low, total 

loading is relatively large because of higher water yields. These areas comprise about 67 

percent of BLM-administered lands in the Upper Basin. Runoff from these areas is 

estimated to contribute more than half of the annual salt load from BLM-administered 

lands in the Upper Basin. 

The BLM is committed to reducing salinity concentrations in the Colorado River sourced 

from its public lands as required by amendments to the Colorado River Basin Salinity 

Control Act of 1974 and mission mandates under the Federal Land Management Policy 

Act of 1976 (FLPMA). The BLM’s primary strategy for reducing salt transport to the 

Colorado River is to minimize erosion from public lands through its existing landmanagement policies and practices. These policies and practices are intended to maintain 

or restore land-health as reflected by key ecological attributes such as soil and site 

stability, watershed function, and biotic integrity. 

The BLM manages public lands according to a multiple-use mandate under the FLPMA. 

Many land-use activities such as livestock grazing, energy development, mining, 

recreation, timber production, utility transmission, and road management increase erosion 

and sediment transport. The BLM attempts to reduce these impacts to help maintain 

land-health standards by utilizing best-management practices; including terms, 

conditions, and stipulations in land-use authorizations; and requiring actions to restore 

lands upon completion of authorized activities. BLM also engages in many activities to 

restore degraded ecosystems that contribute excessive sediment and salts to Colorado 

River Basin watersheds. These activities include constructing and maintaining gradecontrol structures, spreader dikes, and retention structures; emergency stabilization and 
33 

rehabilitation efforts following wildfires; removal of invasive plant species, channel 

stabilization and other riparian enhancements; maintaining road culverts; remediation of 

abandoned mine lands, and fire fuels reduction treatments. Salinity reductions for many 

of these activities continue to be difficult to quantify and report to the Forum because of 

factors such as the lack of adequate understanding about mobilization and transport of 

salts from rangelands and inability to conduct effectiveness monitoring for all projects. 

Program Administration 

The BLM established a Salinity Coordinator position in 2003 to coordinate activities in 

state offices, develop and refine approaches and protocols to advance abilities to 

understand transport mechanisms and quantify reductions achieved from landmanagement activities, and improve collaboration with the Reclamation Salinity Program 

Manager and Natural Resource Conservation Service Salinity Program Coordinator. 

The BLM allocated $750,000 in FY2012 from its Soil/Water/Air (SWA) subactivity to 

support projects specifically relating to salinity control program objectives in its Upper 

Basin State Offices. Project funding is allocated towards proposals submitted by State 

Offices through the BLM Budget Planning System and prioritized using input from the 

Salinity Coordinator. Funding is allocated between planning, science, and on-the-ground 

implementation projects. Projects funded in FY2012 are described below in the State 

Reports section. Additional funding is allocated each year from the SWA subactivity to 

support labor and operations for the Salinity Coordinator. The BLM applied an 

additional $100,000 in lapsed labor funds from the vacant Salinity Coordinator position 

to initiate a collaborative study with Reclamation, Forum, Agricultural Resource Service, 

and USGS addressing salt mobilization and transport from rangelands. 

In addition to the funding allocated from the SWA subactivity, millions of dollars are 

expended annually by other BLM programs and authorized users of public lands on 

watershed management, restoration, and mitigation activities that reduce erosion and 

contribute to salinity-control efforts. As previously indicated, the BLM is not able to 

report reductions accomplished through many of these efforts of technical and 

programmatic issues, but is working to develop approaches needed to quantify 

reductions. 

State Activities since last Progress Report 

Each BLM State Office prioritizes the salinity control activities which will provide the best 

results for their given circumstances and funds available. 

Arizona 

- Flat Top Dam system, a component of the Fort Pierce flood and salinity control 

system. 

o Conditions of 5 dikes in upper Clayhole Valley were assessed. 

o Over 150 miles of road maintenance completed, reducing dust and 

erosion. 

o Range standards and guides assessment reports completed on 25,000 acres 

of grazing allotments on saline soils. AMP’s are being revised to address 

problems on the saline soils. 
34 

o Cattle temporarily removed from recently burned allotments. 

Colorado 

- Badger Wash 

o Study to assess contributions of grazing on Mancos Shale to in-stram 

salinity. 

- Coal mine impact study – 

o Monitor any changes in surface or groundwater quality in the Book Cliff 

area north of Fruita, CO. 

- Piceance Basin 

o Monitor precipitation along with conductivity and flow on sites on the 

White River, Piceance CK and Yellow Ck. This will help to determine 

potential impacts from oil and gas development in the basin and 

understand salinity and selenium loading in the White River. 

- Dust Sampling 

o Operating dust samplers in Craig and Grand Junction, CO to study the 

effects of dust events on the albedo of the snowpack, and any associated 

changes in runoff and erosion. 

New Mexico 

- Road improvements 

o Improve local dirt roads on BLM lands to reduce amount of sediment 

reaching water ways in San Juan River basin. 

- Vegetation Treatments 

o Pinyon-Juniper and sagebrush selectively thinned to promote grass and 

native vegetation production to help curtail soil erosion and improve 

watershed function in San Juan River basin. 

- Silt Traps 

o Roughly 300 silt traps were built to help curtail sediment and salt loading, 

from oil and gas well pads and road construction, helping to improve the 

water quality in the San Juan basin. 

- Riparian 

o Russian olive trees and saltcedar treated and removed to help native 

vegetation become reestablished. Noxious exotic weeds inventoried and 

sprayed. Rock dams constructed to stabilize the drainage, catch sediment 

and promote establishment of vegetation on newly deposited sediment. 

The rock dams were designed to reduce amount of sediment and salt 

reaching the San Juan River. 

- La Manga Canyon Watershed Restoration 

o 200 acres of rangeland in the La Manga drainage was cleared for a mow 

and drill seed project to reduce erosion during snow melt and storm runoff 

events. Project included recontouring of disturbed hill slopes, 

construction of sediment retention dam, soil preparation and reseeding. 

Test plots were monitored and sediment and pasture fences maintained. 
35 

Utah 

Utah continued to implement the Healthy Lands and Watershed Restoration program, 

which focused on improving habitat, vegetation, and improving water quality by 

improving vegetation cover and reducing erosion from BLM lands. 

- Utah Watershed Restoration Initiative 

o This is a multi-agency Federal, State, and private partnership treating 

lands of various ownerships with an emphasis on watershed improvements 

and long-term habitat restoration. Although the projects are being 

conducted statewide, approximately 13 of these were located on BLM 

lands in the Colorado Plateau Ecoregion and have significant potential 

long-term benefits; reducing runoff, erosion, sedimentation and salinity to 

the Colorado River Basin. Additionally Moab BLM has entered into an 

agreement with the Dolores River Restoration Partnership, which has 

multiple NGOs, private, BLM, and other federal partners focusing efforts 

on the Dolores River. 

o Over 12,900 acres of BLM lands and 42.44 miles of stream corridor 

within the Colorado Plateau were treated in 2012 under this program, 

although total treatment area including other Federal, State and private 

lands as part of the cooperative effort is well more than 2 to 3 times that 

number. Treatments include riparian restoration, tamarisk and Russian 

olive removal, sagebrush restoration (Dixie-harrow and seeding), removal 

of juniper through bullhog and hand thinning methods, wildlife and 

rangeland seeding, cheatgrass treatment and reseeding degraded 

rangelands, and other similar projects. 

- Climate Monitoring 

o Utah maintains a long-term climate monitoring program. Data are used in 

project planning as well as for interpreting results from other monitoring 

data such as silt fences and sedimentation studies. Soil, Water, Air 

appropriated funding was used to implement crucial upgrades and 

maintenance of equipment. This data will be merged with other data sets 

and used in longer-term climate analyses for the Colorado Plateau as well 

as interpreting ongoing studies related to salinity and erosion within the 

state. 

o Study of land use activities and any associated dust impact on snow albedo 

and the change in snow melt and water loss via evaporation and 

transpiration. 

- Riparian Restoration 

o BLM Utah has been conducting weed treatments, primarily Russian olive 

and tamarisk removal as well as treatment of noxious weeds such as 

purple loosestrife, perennial pepperweed, and Russian knapweed in order 

to improve riparian habitat. Over 750 acres of streamside were treated and 

over 11,000 acres were surveyed for weeds and riparian improvement 

needs. Over 24,000 acres were treated and over 93,000 acres surveyed on 

adjacent uplands. 

- Factory Butte OHV impact and soil study 

o ongoing 
36 

- Pariette Wetlands 

o Pariette Wetlands are an oasis in the Uinta Basin of northeastern Utah. 

The system is a large artificially-augmented wetland developed in 1972 to 

improve waterfowl production and provide seasonal habitat for other 

wildlife species. It encompasses 9,033 acres, 2,529 of which are classified 

wetlands or riparian and is the largest BLM wetland development in Utah. 

Elevated levels of Se have been measured in the wetland and pose concern 

for wildlife using the wetlands. Management of the Pariette wetlands is a 

long-term and multi-faceted endeavor. Major components of this include 

facility operation and monitoring the wetland area for wildlife 

management and salinity/water-quality control. 

o Completion of facility maintenance including clean-out and removal of 

sediment from the water diversion structures, rebuilding dikes and 

invasive weed control. 

o Collection of water quality sampling as part of our cooperative agreement 

for water quality monitoring with Utah Division of Water Quality. Data 

collected included flow (cfs), specific conductance (uS/cm), temperature 

(deg C), pH, dissolved oxygen (mg/l), and salinity (ppt). 

o Salinity program funding is being used to support a study through Utah 

State University Uintah Basin Hydrology Faculty. This study will help 

land managers determine whether or not the salt and associated 

contaminants in the Pariette Draw can be managed. This framework will 

provide temporal and spatial geochemical data for salt and associated 

contaminants. 

o The goal of these studies is to determine the processes responsible for 

regulating bioavailable Se within the wetland, so as to predict, prevent, 

and mitigate the potentially toxic build-up of bioavailable Se. 

- Grazing Exclosures 

o The BLM Moab Field Office used funds to construct grazing exclosures in 

sensitive soils including those with salinity content, drought intolerant, 

high wind/water erosion rating, or low productivity. With these and other 

existing exclosures, most grazing allotments with more than 10 percent 

saline soils in the Moab Field Office now have a long term reference site 

in that allotment. 

o These exclosures are good reference sites to better understand impacts to 

moderately saline soils (>8 mmhos/cm) from grazing activity. Most sites 

are located adjacent to long term range trend study sites. Data from these 

long term study sites can help direct grazing management actions to 

ensure good soil conditions. With stable soil conditions, soil erosion and 

associated salinity loading to the Colorado River Basin is minimized. 

Wyoming 

It is recognized that surface disturbance has increased due to BLM approved activities, 

mostly oil and gas development, and this may reduce the effectiveness of these salinity 

control projects and related management actions. However, every oil and gas 
37 

development project includes best management practices to control soil erosion and salt 

mobilization and reclamation of disturbed areas to promote rapid revegetation and 

stabilization of site disturbances. 

- Progressive soil surveys 

o Improving the quality of soil resource impact analysis and mitigation 

prescription by BLM in the O&G development activities; in addition, are 

also providing the O&G industry with planning and assessment tools that 

will allow companies to prepare better operational plans and Storm-water 

Pollution Prevention Plans 

o Providing critical input data for the tailoring of the Automated Geographic 

Watershed Assessment (AGWA) modeling toolkit for the Upper Colorado 

Basin area. Application of this toolkit allows BLM specialists to identify 

watersheds most vulnerable to surface disturbing actions and enables users 

to select the best management options to minimize erosion, runoff and salt 

loading to waterways. 

o Helping to identify and protect fragile soil areas (that if disturbed, would 

impact water quality), aid in control of invasive plant species, select 

appropriate restoration strategies, and select appropriate management 

strategies. BLM, State regulatory agencies, O&G companies, and 

landowners will all benefit from the availability of high quality digital 

spatial and tabular soils data for their respective needs and applications. 

- Automated Geographic Watershed Assessment modeling toolkit 

o The BLM is continuing a cooperative project with the University of 

Wyoming (UW), Wyoming Geographic Information Science Center 

(WyGISC) and the Department of Renewable Resources to further refine 

the AGWA modeling toolkit and apply it in environmental impact analysis 

for oil and gas projects and subsequent project management within the 

Upper Green (Colorado) River Basin in Wyoming. 

o The objective of this project is to assist in predictive risk modeling of salt 

mobilization and transport using improved soil salinity mapping and 

modeling. BLM is working with the University Project Team to perform 

field research to establish accurate soil salinity and erosion relationships, 

parameterize existing functional hydrologic models, and develop a 

mechanistic understanding of salt transport. 

o This team is currently assisting the BLM in using these tools to prepare 

analysis models for the LaBarge and NPL oil and gas projects. These 

efforts will provide the quantitative data needed to manage surface 

disturbing energy development projects in a manner that controls soil 

erosion and salinity loading. 

- Road Maintenance 

o Road construction and use increases erosion and sediment transport. 

Operators are required to provide the BLM with engineered designs and 

use best management practices to construct new roads. Additionally, 

hydrologic analyses are required for properly sizing and placing culverts 

that are needed in larger, more complex ephemeral and perennial systems. 
38 

It is assumed that smaller quantities of sediments and salts are reaching 

drainages due to these improvements in design. 

- Grazing Management 

o Improvements in grazing management on approximately 43,000 acres 

reduced runoff and erosion, the improvements included the development 

of 4 impoundments and 3 spring developments that encourage cattle to 

stay out of riparian areas and concentrate use on upland areas. 

o In response to the larger fires outside of BLM managed lands in 2012, 

several BLM grazing allotments in the Northern extent of the Green River 

Basin have been closed. The costs to the government are the loss of the 

grazing fees and taxes resulting from income by the ranchers. The exact 

amount of potential salt savings that could occur in the following years is 

unknown and has a potentially wide variation but the benefits to 

vegetation and soil stability should be considerable. 

- Oil and Gas Activity 

o 19 Wells are plugged and abandoned in the Colorado River Basin. Wells 

that have been plugged and abandoned are reclaimed with native 

vegetation and no longer contribute salt and sediment into the watershed. 

This includes the wellpads as well as the access roads associated with the 

wellpads. 

- Reservoir Repair 

o Nine reservoirs were repaired in FY 2012; no new reservoirs were 

constructed. 

Due to the historically high runoff rates from the winter and spring, many 

reservoirs required repairs. It is difficult to quantify the amount of salts 

being retained within the reservoirs due to different holding capacities, 

different soils, and variable precipitation and runoff rate. However, most 

reservoirs are effective in retaining salt if built and maintained 

sufficiently. 

- Vegetation Treatments 

o Approximately 4 miles of stream were planted with willow, current, birch, 

sedge, rush, and buffalo berry in order to revegetate disturbed banks. The 

amount of sediment/salt loading to streams will be reduced once this 

vegetation is established. 

o There were no mechanical vegetation treatments within the Colorado 

River Basin, but approximately 3000 acres were treated with herbicide in 

order to encourage new vegetative growth and increase vegetative cover, 

thereby reducing erosion. 
39 

Table 6 – BLM Salt Retention Estimates for Fiscal Years 2006 – 2012

Project 

Category 

SALT RETAINED IN TONS/YEAR1

 

FY 20064 FY 20074 FY 2008 FY 2009 FY 2010 FY 2011 FY 2012 

POINT SOURCE2 14,600 14,600 14,600 14,600 14,600 14,600 14,600 

NONPOINT SOURCE3 71,900 71,900 81,900 71,900 85,300 111,400 111,400 

ALL PROJECTS 86,500 86,500 96,500 86,500 99,900 126,000 126,000 

1. Rounded to the nearest 100 tons. 

2. BLM’s Salinity Report to Congress through the year 2002, plus the plugging of 2 wells in Utah during 

 FY 2004 (approximately 5,000 tons/yr). 3. Amount that could be calculated, i.e., this is a minimum. 

4. When the program was re-structured in FY 2006, we did not have a complete accounting the 1st year or even 

the 2nd year. As a result, the tons-of-salt-retained number on BLM administered land in the Upper Colorado 

River Basin (UCRB) was low. FY 2006 and FY 2007 numbers have been changed to reflect tonnage retained in 

FY 2009, because after 4 years on the new system, FY 2009 tonnage is probably a better estimate. Projects 

can become less effective in retaining salt over the years, but there is enough erosion control going on 

constantly in the UCRB on public land, that the tonnage is probably closer to FY 2009 than it was to the low 

incomplete numbers originally reported for FY 2006 and FY 2007. 

U.S. Department of Agriculture (USDA) 

The NRCS of the USDA conducts Colorado River Basin Salinity Control activities 

primarily under the authorities of the Environmental Quality Incentives Program (EQIP). 

EQIP was enacted with passage of PL104-127, Federal Agricultural Improvement Act of 

1996, a.k.a. “1996 Farm Bill.” 

EQIP has been reauthorized twice; by PL 107-171, The Farm Security and Rural 

Investment Act of 2002, the “2002 Farm Bill” and by PL 110-246, The Food, 

Conservation, and Energy Act of 2008, the “2008 Farm Bill.” The 2008 Farm Bill 

expired September 30, 2012; however, the Consolidate and Further Continuing 

Appropriations Act of 2012 extended the authorization of EQIP through September 30, 

2014. 

Through EQIP, NRCS offers voluntary technical and financial assistance to agricultural 

producers, including Native American tribes, to reduce salt mobilization and transport to 

the Colorado River and its tributaries. Within the eleven approved salinity project areas, 

producers may be offered additional financial incentives to implement salinity control 

measures with the primary goal of reducing offsite and downstream damages and to 

replace wildlife habit impacted as a result of the salinity measures. 

 In FY 2012, $12.4 million of appropriated EQIP funding was obligated into new land 

treatment contracts with agricultural producers in project areas in Colorado, Utah, and 

Wyoming. These contracts, when fully implemented will provide more than 13,000 tons 

of annual salt control. 

New Salinity Projects and Investigations 
40 

Henrys Fork (of the Green River), WyomingThe Henrys Fork Salinity Control Project 

was adopted by NRCS in May 2013. This project area encompasses 69,929 acres in 

Sweetwater and Uinta Counties, Wyoming, and Daggett and Summit Counties, Utah. The 

entire Henrys Fork watershed is about 306,000 acres and is a tributary to the Green River 

which is a major tributary to the Colorado River. 

Of the 20,709 irrigated acres within the project area, NRCS expects to improve on-farm 

irrigation application systems and reduce deep percolation and salt loading from about 

14,000 acres, resulting in a salt load reduction of 6,540 tons annually. 

West Black’s Fork, Wyoming 

An area of some 28,000 acres of irrigated pasture and hayland near Lyman, Wyoming, 

contribute salt to the Blacks Fork River, tributary to the Green River. While a large 

portion of the geology contributes little salt, about 10,000 acres may contribute 

significant amounts of salt from canal and ditch seepage and deep percolation from water 

applied to fields. 

The Wyoming Water Development Commission provided a significant grant to the 

Austin-Wall Canal Company resulting in a comprehensive plan to modernize the 

irrigated areas within their service area. NRCS anticipates that, in the near future, the 

Company will begin replacing earthen canals with buried pipelines that will provide 

pressure to operate sprinklers on the irrigated lands. NRCS intends to use its regular 

EQIP authority to assist producers in the area who want to modernize their irrigation 

systems. Such improved systems will provide significant salt control benefits. 

San Juan Basin, New Mexico and Arizona 

The first phase of the “Shiprock Pilot Project” to control salt was completed by the San 

Juan River Dineh Water Users, Inc. (SJRDWU, Inc.) in 2011. A leaky earthen lateral 

supplied water to 12 Navajo Nation farmers on 168 acres of cropland. The SJRDWU, 

Inc. completed the construction using their own resources and a grant from the Bureau of 

Reclamation. The SJRDWU, Inc. also reserved an eight acre parcel of land and has 

completed practices to replace wildlife habitat values that were lost due to the pipeline 

installation.

The NRCS has been actively promoting the use of EQIP to improve the on-farm 

irrigation systems served by the pipeline. EQIP applications have been received but, to 

date, no installation has occurred. As salt loading is quite high from agriculture along the 

San Juan River, it is hoped that this pilot project will encourage and accelerate salinity 

control. The SJRDWU, Inc. has expressed continuing interest in improving the irrigation 

delivery and application systems within their service area. 

Areas Beyond Current Project Boundaries 

NRCS has undertaken to identify salt loading and salinity control from irrigated crop, 

pasture and haylands scattered widely throughout the Upper Colorado River Basin but 

outside of the existing project areas. With the assistance of the U.S Geological Survey 

(USGS) and the Bureau of Reclamation, NRCS has been able to make use of the 

SPARROW model to assess salt loads outside of the existing salinity project areas. While 
41 

the assessment is ongoing and will require considerable refinement, preliminary analysis 

indicates that as much as 50,000 tons of salt control has occurred in Utah and Colorado 

outside the project areas. 

In 2012, Colorado and Utah NRCS developed EQIP contracts with water quality benefits 

including salt control outside of the approved project areas but within the Colorado River 

Basin. 

 Colorado, obligated $166,000 on 264 acres for 281 tons of planned salt control in 

the counties of La Plata, Archuleta, and Montrose. 

 Utah, obligated $1.6 million on 2,420 acres for 1,310 tons of planned salt control; 

all within Wayne County. 

Monitoring and Evaluation 

Project offices continue to monitor and evaluate the effectiveness and quantity of salinity 

control, wildlife habitat, and economic performance replacement in order to improve the 

overall performance and management of the program. Generally, the program continues 

to function effectively and economically, though the overall cost per ton of salt control 

continues to rise in some areas however, when adjusted for inflation the current cost 

effectiveness compares favorably with the projected costs at the time of the adoption of 

the respective projects. It is also noted that additional efforts are needed to identify and 

implement valuable, low-maintenance, sustainable wildlife habitat replacement. The 

individual Monitoring and Evaluation reports for FY 2011 for each project can be found 

on the world-wide-web at; http://www.usbr.gov/uc/progact/salinity/index.html 

Active Salinity Control Projects 

USDA-NRCS is providing technical and financial assistance to landowners and operators 

to implement on-farm salinity control measures in eleven approved project areas in three 

Upper Basin states. 

Table 7 – Active Salinity Control Projects 

Project Area 

State Project (Potential Irrigated Acres) USDA Servicing Office

 

Colorado Grand Valley 50,000 Grand Junction

Lower Gunnison River 171,000 Delta and Montrose

McElmo Creek 29,000 Cortez

Mancos Valley 11,700 Cortez

Silt 7,400 Glenwood Springs

Utah Uinta Basin 226,000 Roosevelt, Vernal

Price/San Rafael Rivers 66,000 Price, Castle Dale

Muddy Creek 6,000 Castle Dale

Manila-Washam 8,000 Vernal

Green River 2,600 Price

Wyoming Big Sandy River 18,000 Farson

Henrys Fork 21,000 Lyman

Total 616,700
42 

Grand Valley, Colorado

Implementation has been underway in this unit since 1979 and NRCS considers that the 

salt control measures of the project have been successfully completed as planned. In 

2010, a status report was compiled from field visits and observations. The report 

indicated that at least 12,000 irrigated acres are no longer in agricultural production. Of 

the remaining 44,700 acres still in production, 42,435 acres or 95 percent had received 

varying levels of treatment. 

As of October 2011, the salt reduction goal of 132,000 tons had been exceeded and more 

than 147,000 tons had been reported as controlled. In 2012, 29 new contracts (of which 

two were Basin States) were signed on 980 acres that will deliver an additional 1,955 tons 

of salt control. 

While the Grand Valley project has been very successful in reaching its salt control goal, 

the wildlife replacement goal remains to be met. Approximately 400 acres of additional 

habitat replacement are required. Negotiations and planning are underway for a 600 acre 

parcel that would achieve the replacement goal. 

Lower Gunnison Basin, Colorado 

This project encompasses the irrigated farmland in the Gunnison and Uncompahgre River 

valleys. With the expansion into the upper headwaters of the Uncompahgre River in 

2010, implementation is now proceeding in Delta, Montrose, and Ouray Counties. 

Implementation was initiated in 1988 in this unit. Nearly 60 percent of the salt control 

goal has been achieved. 

Interest remains high in the project area. Sixty new contracts (six were BSP) for about 

$4.5 M were developed in 2012 on 2,442 acres for planned salt control of 4,643 tons. 

About 30 percent of new projects are sprinkler systems, 62 percent are improved surface 

systems and 7 percent are micro-spray or drip. 

Mancos River, Colorado 

This project, near the town of Mancos, Colorado, was initiated and approved for funding 

and implementation by USDA-NRCS in April 2004. Currently, about 50 contracts have 

been developed with EQIP and Basin States Parallel funds. Five new contracts for 

$72,000 were developed on 109 acres in 2012. Planned salt control from these new 

contracts is 85 tons annually. One third of the contracts were sprinkler systems. 

McElmo Creek, Colorado 

Implementation was initiated in this unit in 1990. Application of salinity reduction and 

wildlife habitat replacement practices continue to be implemented in this area with 

sprinkler systems, underground pipelines, and gated pipe being installed. In 2012, 26 

new contracts were developed on 507 acres that will provide 646 tons of salt control 

when fully implemented. Sixty-two percent of the new projects were high-efficiency 

sprinkler systems. The project has attained slightly over 60 percent of its salt control 

goal. 
43 

Silt, Colorado 

The first applications were funded in 2006. The cumulative cost effectiveness for these 

new contracts is $72 per ton which falls midway among the other active project areas. 

Several wildlife projects have been identified. Applications are a mix of improved 

surface and sprinkler irrigation systems. 

Uinta Basin, Utah 

Implementation began in this unit in 1980. The original salt control goal was reached 

several years ago but about 60,000 acres might still be improved. Producer participation 

is exceeding the original projections. Fifty eight EQIP contracts (including one wildlife 

habitat contract and three Basin States contracts) were reported in 2012. These contracts 

obligate nearly $1.6M to control about 1,600 tons of salt. All irrigation improvements 

were either sprinklers, buried pipelines or a combination of the two. Installation of a 

Reclamation- funded project near the city of Roosevelt accelerated the rate of 

applications in Duchesne County. 

A significant number of systems have reached or are nearing the end of their useful life. 

While these systems are a lower priority than first-time improvements, NRCS has begun 

providing incentives for replacement or up-grading. NRCS has also organized a team to 

analyze the issues raised by the farmer-demand for incentives to replace aging systems. 

Issues of environmental benefits vs. cost, and program authority must be considered 

within the larger national framework of administering the EQIP program. 

Price-San Rafael, Utah 

This project is approaching 60 percent achievement of its salt control goal. In 2012, 37 

new contracts (including two wildlife and two Basin States contracts) obligated about 

$1.9 M on 1,444 irrigated acres. When implemented, these measures will control about 

4,000 tons of saltand provide habitat replacement. The on-farm portion of the 

Huntington-Cleveland Project is in the final two years of contracting. The Cottonwood 

Creek Irrigation Company service area is the last large untreated area of the Price-San 

Rafael Salinity Control Project. A large number of applications were received there in 

2012 and NRCS anticipates developing numerous contracts there in 2013 and beyond. 

Muddy Creek, Utah 

There were no new contracts developed in the Muddy Creek area in 2012, however as a 

portion of the canal serving the area has been piped, NRCS anticipates receiving a few 

applications in 2013.

Green River, Utah 

One EQIP contract was developed in the project area in 2012 that will control 1,310 tons 

when fully implemented. Interest remains high but off-farm infrastructure improvements 

are needed to allow on-farm systems to operate properly and efficiently. Irrigation 

continues to expand, particularly on the plateau to the east of the Green River but, as all 

of the new irrigation systems are high-efficiency sprinklers, NRCS does not anticipate a 
44 

significant increase in salt loading to the river. These expansions are not eligible for 

EQIP assistance. 

Manila-Washam, Utah/Wyoming 

Astride the Utah-Wyoming border, and adjacent to the shores of Flaming Gorge 

Reservoir, the Manila-Washam Project is the newest, authorized project area. This area 

of 11,000 acres of irrigated pasture and hayland contributes about 53,000 tons of salt 

annually to the Green River. Nearly 2000 acres have been treated or contracted since the 

first plans were developed in 2007. All new irrigation systems have been some form of 

sprinkler system, such as side roll, pods, or center pivots. 

Big Sandy River, Wyoming 

Implementation has been underway in this unit since 1988. Approximately 13,500 acres 

of the planned 15,700 acres have been treated (86 percent) and about 68 percent of the 

salt control goal has been reached. Producers also report that the water savings from 

improvements in irrigation systems now allows a full irrigation season of water for the 

entire irrigation district. In 2012, no new contracts were developed. 

Table 8 - USDA Salinity Control Unit Summary Through 2012 

 1Controls Potential Percent Costs Annualized Projected 2Cost/ton 

Unit (tons) (tons) of Goal Costs total cost 

Mancos River, CO 4,325 11,940 36% $6,849,366 $567,812 $18,909,001 $131 

Muddy Creek, UT 61 11,677 1% $117,812 $9,767 $22,552,307 $160 

Manila-Washam, UT 8,149 17,430 47% $7,027,276 $582,561 $15,030,730 $71 

Silt, CO 2,139 3,990 54% $3,998,487 $331,475 $7,458,608 $155 

McElmo Creek, CO 29,289 46,000 64% $22,420,893 $1,858,692 $35,213,257 $63 

Uinta Basin, UT 149, 714 140,500 107% $111,335,705 $9,229,730 $104,464,820 $62 

L. Gunnison, CO 112,987 186,000 61% $74,120,491 $6,144,589 $122,017,677 $54 

Price/San Rafael, UT 88,616 146,900 60% $43,891,498 $3,638,605 $72,759,559 $41 

Grand Valley, CO3 148, 440 132,000 112% $56,713,677 $4,701,564 $50,432,534 $32 

Big Sandy, WY 56,810 83,700 68% $13,560,491 $1,124,165 $19,979,107 $20 

Green River, UT 178 6,540 3% $86,940 $7,207 $3,194,312 $40 

 

Totals 600,735 786,677 76% $340,122,636 $28,196,167 $472,011,913 $47 

1Includes Off-farm funded with EQIP or Basin States Parallel funds

2Cost per ton based on amortization over 25 years at 6.625% interest. 

3

Grand Valley includes 35,300 tons for on-farm ditches, not part of in-field control.

Since 2010, 5,457 tons of out-of-pocket salt control has been contracted at a weighted cost per ton of $156.
45 

Figure 13 – NRCS On-Farm Salt Control Through 2012

Bureau of Reclamation 

Basinwide Salinity Control Program (Basinwide Program) 

One of the greatest advantages of the salinity control program comes from the integration 

of Reclamation’s program with USDA’s program. Water conservation within irrigation 

projects on saline soils is the single most effective salinity control measure found in the 

past 30 years of investigations. By integrating USDA’s onfarm irrigation improvements 

with Reclamation’s off-farm improvements, significantly higher efficiencies can be 

obtained. If landscape permits, pressure from piped delivery systems (laterals) may be 

used to drive sprinkler irrigation systems at efficiency rates far better than those normally 

obtained by flood systems. Reclamation now has much greater flexibility (in both timing 

and funding) to work with USDA to develop these types of projects. 

Another significant advantage of the existing salinity program is that projects are 

“owned” by the proponent, not Reclamation. The proponent is responsible to perform on 

its proposal. Costs paid by Reclamation are controlled and limited by an agreement. Yet, 

unforeseen cost overruns can occur. The proponent has several options: the project may 

be terminated or the proponent may choose to cover the overruns with their own funds or 

borrow funds from State programs. The proponent may also choose to reformulate the 

project costs and recompete the project through the entire award process. For example, 

pipeline bedding and materials costs for the Ferron Project were underestimated in the 

proposal and subsequent construction cooperative agreement. The proponent was denied 

permission to award materials contracts for the pipeline, since the costs were beyond 
46 

those contained in the agreement. After months of negotiations and analysis, the 

proponents elected to terminate the project, reformulate it, and recompete against other 

proposals the following year. Their project was found to be competitive at the 

reformulated cost and was allowed to proceed. 

Funding Opportunity Announcement (FOA) 

Reclamation’s Upper Colorado (UC) Region released a FOA on August 1, 2012, 

requesting applications for salinity control projects that reduce salinity contributions to 

the Colorado River system. 

Applications were selected through a competitive process under the evaluation criteria set 

forth in the FOA. Applications were evaluated and ranked by an Application Review 

Committee (ARC). Reclamation and/or the state agency proceeded to award agreements 

to the applicants of the highest ranked applications. Starting with those applications with 

the highest ranking, awards were made until the anticipated available funding for the next 

2 to 3 years was awarded. 

All salinity projects are required to replace incidental wildlife habitat losses concurrent 

with construction of salinity features and maintain this habitat for the life of the project.

Price – San Rafael River Basins, Utah 

Huntington Cleveland 

Irrigation Company 

(HCIC) Project: The 

Project is located in 

northern Emery County, 

in and around the towns 

of Huntington, Lawrence, 

Cleveland, and Elmo. 

The Project was selected 

in the 2004 Request for 

Proposals (RFP) and 

awarded a cooperative 

agreement in September 

2004. A new cooperative 

agreement was executed in November 2006, and was modified again in September 2009. 

Approximately 350 miles of open earthen canals and laterals are being replaced with a 

pressurized pipeline distribution system (Distribution System) to accommodate sprinkler 

irrigation on about 16,000 acres. Funding for this project is being shared between 

Reclamation’s Basinwide Program, HCIC including a loan from the Utah Division of 

Water Resources, NRCS’s EQIP, the Parallel Program, and Rocky Mountain Power, 

formally known as Utah Power and Light. The last of Reclamation’s share of 

$17,116,336 for the Off-farm Distribution System was obligated in 2008. Reclamation 

can provide up to an additional $6,000,000 in funding equally 50/50 with HCIC funds for 

completion of the Distribution System. Since 2009, Reclamation has provided over 

$4,000,000 in additional funding. The Project, scheduled to be completed in 2013, will 

Figure 14 - Price-San Rafael Irrigation Improvements. 
47 

result in the annual reduction of 59,000 reportable tons of salt in the Colorado River at an 

anticipated combined Federal cost of approximately less than $100/ton. Of the 59,000 

tons of salt, 13,000 are attributed to the Off-Farm Distribution System and 46,000 tons 

are attributed to the On-Farm Distribution System and the on-farm salinity control 

measures (sprinklers).

Cottonwood Creek Irrigation Improvement Project: The $6,509,548 Cottonwood Creek 

Irrigation Improvement Project is located in Emery County, west of Castledale, Utah. It 

was selected from the applications received in the 2008 FOA. A Cooperative Agreement 

was executed in February 2010. Construction began in May 2011, and the project is 

expected to be operational for the 2013 irrigation season. This project replaced 

approximately 31 miles of earthen canals and laterals with a pressurized pipeline system 

resulting in a reduction of 2,094 reportable tons of salt in the Colorado River. It is 

expected that the pressurized pipeline will induce on-farm improvements resulting in the 

annual reduction of an additional 9,100 reportable tons of salt. It is anticipated that the 

project will result in the total annual reduction of 11,194 reportable tons of salt in the 

Colorado River at an anticipated cost of approximately $59 per ton of salt. 

Uintah Basin, Utah 

Ouray Park Canal 

Rehabilitation Project: 

This project is located in 

Uintah County in the 

vicinity of Gusher, Utah. 

It was selected from the 

applications received in 

the 2010 FOA. A 

Cooperative Agreement 

was executed in 

September of 2011, for 

the amount of 

$2,676,000. This project 

will replace 

approximately 5.2 miles of 

the Ouray Park Canal with 

irrigation pipe completing a 20.5 mile system. This allows for total abandonment of the 

13 mile Ouray Valley Canal which carried storage water for one month per year due to 

previous salinity control agreements. The project results in the annual reduction of 1,662 

reportable tons of salt in the Colorado River at an anticipated cost of approximately 

$79.82 per ton of salt. The project was begun in the fall of 2011 and will be completed in 

the spring of 2013.

Hancock-State Road Salinity Reduction Project: This project is located in Duchesne and 

Uintah Counties in the vicinity of Roosevelt, Utah. It was selected from the applications 

received in the 2010 FOA and funded with funding from the Basin States Program. A 

Cooperative Agreement was executed in March of 2012, for the amount of $2,315,250. 

This project will replace approximately 20.83 miles of earthen canal and laterals with 

irrigation pipe resulting in the annual reduction of 1,759 reportable tons of salt in the 

Figure 15 - Salinity in Uinta Basin Unit Area. 
48 

Colorado River at an anticipated cost of approximately $65.25 per ton of salt. The 

project was begun in the fall of 2011 and approximately 50 percent was in service for the 

2012 irrigation season. Project completion is scheduled for spring of 2013. 

Big Sandy Project, Sweetwater County, Wyoming 

Eden Valley, Eden Canal, Laterals E-5 and E-6 Project: This project was selected in the 

2010 FOA. A Cooperative agreement was executed in September of 2011, for the 

amount of $1,712,968.50. This project will replace approximately 1.43 miles of earthen 

laterals with irrigation pipe and line 1.38 miles of the Eden Canal with an impermeable 

layer resulting in the annual reduction of 1,101 reportable tons of salt in the Colorado 

River at an anticipated cost of approximately $77.13 per ton of salt. Laterals E-5 and E-6 

are completed, and work on the Eden Canal is scheduled to begin in the fall of 2012 and 

to be completed in the spring of 2013.

Eden Valley, Farson/Eden Pipeline Project: This project was selected in the 2008 FOA. 

A Cooperative Agreement was executed in February of 2009, for the amount of 

$6,453,072. This project will replace approximately 24 miles of earthen laterals with 

irrigation pipe resulting in the annual reduction of 6,594 reportable tons of salt in the 

Colorado River at an anticipated cost of approximately $52.57 per ton of salt. Laterals E7, E-8, and E-13 are completed, and work on the West Side Canal is currently being 

accomplished. The project is scheduled to be completed by 2013. 

Gunnison Basin, Colorado 

Uncompahgre Valley Water Users Association (UVWUA) Phase 4 Project: As a result 

of the 2008 FOA, the UVWUA was awarded a cooperative agreement for Phase 4 of the 

ESL in December 2008. This phase involves an additional 11 miles of laterals under the 

Selig and East Canal systems and the reduction of about 3,700 tons of salt loading 

annually at a cost of $29.46 per ton of salt. Approximately $2 million of salinity-control 

funding will be supplemented with approximately $800,000 from a Section 319 grant 

obtained through the Colorado Division of Public Health and Environment. Construction 

of one short lateral was completed in FY 2009. Additional laterals were completed in 

FY2010-11 and the remaining portions of Phase 4 were completed in 2012.

UVWUA Phase 5 Project: As a result of the 2010 FOA, the UVWUA was awarded a 

$4.3 million cooperative agreement for Phase 5 of the ESL. This phase involves an 

additional 19 miles of laterals under the Selig and East Canal systems and the reduction 

of about 5,034 tons of salt loading annually at a cost of $42.53 per ton of salt removed. 

Construction began in November 2011 and will continue through 2015.

UVWUA Phase 7 Project: As a result of the 2010 FOA, the UVWUA was awarded a 

$3.2 million cooperative agreement for Phase 7 of the ESL. This phase involves an 

additional 12.7 miles of laterals under the Selig and East Canal systems and the reduction 

of about 3,029 tons of salt loading annually. The cost is estimated at $52.11 per ton of 

salt. Construction will begin in the fall of 2012 and will continue through 2016.

Grandview Canal and Irrigation Company Project: Awarded from the 2008 FOA, this 

project involves piping a portion of the Grandview Canal and several laterals in an area 

tributary to the North Fork of the Gunnison River near Crawford in Delta County. In 

July 2009, Reclamation entered into an agreement to provide $5.3 million to pipe 4.8 
49 

miles of main canal and 5 miles of laterals and convert about 900 acres of currently 

flood-irrigated farmland to sprinkler irrigation. Construction began in September 2010 

with completion expected by late 2012. The remaining work includes habitat mitigation. 

The project is expected to reduce salt loading by 6,400 tons/year at a cost of $56.84/ton.

Lower Stewart Pipeline Project: Awarded from the 2010 FOA, this project involves 

piping a portion of the Stewart Ditch & Reservoir Company (SDRC) existing unlined 

canals in a tributary to the North Fork of the Gunnison River near Paonia, Colorado. In 

September 2011, Reclamation entered into an agreement to provide up to $6.0 million to 

pipe 11.5 miles of existing canals with an expected salt load reduction of about 10,920 

tons/year with an estimated cost of $27.24/ton. Construction will begin in the fall of 

2012.

Minnesota Ditch Irrigation Salinity Control – Project 1: Awarded from the 2010 FOA, 

this project involves piping a portion of the Minnesota Canal & Reservoir Company 

(MCRC) existing unlined canals in a tributary to the North Fork of the Gunnison River 

near Paonia, Colorado. In September 2011, Reclamation entered into an agreement to 

provide up to $3.94 million to pipe 5.2 miles of existing canals with an expected salt load 

reduction of about 3,263 tons/year at a cost of $59.91 per ton of salt removed. 

Construction will begin in the fall of 2012.

C Ditch/ Needle Rock Project: Awarded from the 2010 FOA, this project involves piping 

a portion of the C Ditch Company (CDC) existing unlined ditches in a tributary to the 

Cottonwood Creek drainage of the Gunnison River near Crawford, Colorado. In July 

2012, Reclamation entered into an agreement to provide up to $1.43 million to pipe 2.5 

miles of existing ditches with an expected salt load reduction of about 1,284 tons/year 

costing $55.4/ton of salt. Construction is anticipated to begin in the fall of 2013.

Clipper Irrigation Salinity Control – Project 4: Awarded from the 2010 FOA, this project 

involves piping a portion of the Crawford Clipper Ditch existing unlined canals in a 

tributary to the Cottonwood Creek drainage of the Gunnison River near Hotchkiss, 

Colorado. In September 2012, Reclamation entered into an agreement to provide up to 

$1.21 million to pipe 3.4 miles of existing canals with an expected salt load reduction of 

about 1,038 tons/years. Cost is expected to be $57.99 per ton of salt removed. 

Construction is anticipated to begin in the fall of 2013.

Reclamation entered into a cooperative agreement in 2008 with the Delta Conservation 

District to map and collect information on water diversion, canals and laterals, and 

irrigation practices in the Lower Gunnison Basin. This information has been needed for 

participation in the FOA process. Mapping in 2012 completed the North Fork, Delta, 

Tongue, and Surface creeks, and Bostwick and Shinn Park areas. Also, a majority of the 

canals were mapped in the Colona area. Additional work is needed to complete the 

Colona and Ridgway areas and finalize the project. The cooperative agreement with 

Delta Conservation District expired on September 30, 2012. Reclamation is looking into 

alternatives to finalize the mapping project for the Lower Gunnison Basin. 

Grand Valley, Colorado 

Grand Valley Irrigation Company (GVIC) Canal Improvement Grant 2010A: As a result 

of selection under the 2010 FOA, the GVIC was awarded a $2.8 million cooperative 
50 

agreement to line about 1.9 miles of their main canal and pipe about 4,100 ft of ditch 

within the Grand Valley. A salt loading reduction of approximately 1,749 tons annually 

is expected at a cost of $79.96/ton of salt removed. The canal lining will consist of a 

PVC membrane with a shotcrete cover and the pipe will be concrete. Construction began 

in December 2011, and will continue through 2015.

Basin State Program 

Section 205 of the Act authorizes Reclamation to expend amounts from the Basin Funds 

to repay the Treasury the reimbursable cost allocation of salinity projects or provide a 

cost share amount. This includes appropriations expended by the NRCS in their salinity 

program. The NRCS has questioned its ability to accept Basin Funds for cost sharing 

directly into its salinity program. Rather than repay the Treasury, the Colorado River 

Basin States (Basin States), NRCS, and Reclamation developed a “Parallel Program” 

(PP). Cost share funds from the Basin Funds have been used to accelerate and 

supplement implementation of the NRCS salinity measures by funding – through state 

agencies in Colorado, Utah, and Wyoming – salinity control measures that are separate, 

but parallel to, the salinity control measures implemented by the NRCS. Reclamation, 

with recommendations from the Basin States, had interpreted the Act to allow funds from 

the Basin Funds to be expended in the PP to further the general purposes of the Act.

To clarify authority for the administration of the PP, the Basin States prepared and put 

forth legislation, through then Senator Salazar’s - CO office, into the 2008 Farm Bill to 

amend the Act and create the Basin States Program (BSP). Public Law 110-246 amended 

the Act and established the BSP. With the creation of the BSP, the PP has been phased 

out and all funds which were not used by December 30, 2012 in the PP have become part 

of the BSP.

Reclamation has determined agencies within the Upper Basin states to be appropriate 

partners and has executed cooperative agreements to utilize the services of these state 

agencies to assist in seeking and funding cost-effective activities to reduce salinity in the 

Colorado River system. Activities will also benefit the Upper Basin states by improving 

water management and increasing irrigation efficiencies. Interagency agreements have 

been executed with the NRCS in the states of Colorado and Utah to provide the technical 

assistance for the BSP.

Utah Department of Agriculture and Food (UDAF) 

Basin States Program (BSP): Significant changes have occurred in UDAFs salinity 

control program. During FY 2012, migration was made from the PP to the BSP. With 

the starting of the BSP, UDAF has moved to close the PP contracts. Early last fall all 

persons holding PP salinity contracts with UDAF were notified by mail that their 

agreements would terminate September 15, 2012. UACD field staff employed with 

salinity technical assistance funds attempted to meet with each agreement holder 

personally to close all existing contracts. 

Progress: UDAF completed the first phase of its web based planning, data collection, and 

grant/contract management tool. The tool is now being used for planning, contracting, 

and data management. All of the PP contracts have been entered into the database 

making the database current. UDAF has also trained planners in field offices to use the 

software and is receiving contracts prepared using the new program. 
51 

Colorado State Conservation Board (CSCB) 

Basin States Program (BSP): The BSP began in Colorado during FY 2012. The BSP is 

made available in the salinity control areas of Silt, Mesa, Grand Valley, Lower Gunnison, 

McElmo, and Mancos. The Bookcliff, Mesa, Delta, Shavano, Dolores, and Mancos 

Conservation Districts receive funds from the CSCB through the current agreement with 

Reclamation that will expire September 30, 2016. 

The projects are planned, designed, and certified by NRCS or District employees based 

upon current NRCS Standards and Specifications. The applications are competitively 

screened and prepared by the NRCS. All applications meeting NRCS planning standards 

that result in an annualized cost per ton of less than $150 and that are also not eligible for 

EQIP are considered for funding depending upon funds available. 

The Districts recommend and refer the application for approval to the CSCB BSP 

coordinator. Upon approval of the application, the Districts enter into a contract with the 

applicant for the irrigation and/or wildlife improvements based on the current NRCS 

payment rate. Technical assistance is provided by NRCS utilizing BSP funding. The 

CSCB is receiving funds from the NRCS for the Districts to provide additional technical 

assistance for program implementation. Implementation of the BSP follows EQIP 

procedures and guidelines as applicable. 

Upon completion of the project, the NRCS certifies the installation, and the District 

provides a payment to the landowner or entity. CSCB provides payments to the Districts 

and periodically requests reimbursement from Reclamation for these payments. Each 

participant signs an operation and maintenance agreement to remain in effect for the life 

of the irrigation improvements installed. The participant is also required to perform 

proper Irrigation Water Management on the fields in which irrigation improvements were 

installed. Participants receive a financial incentive for performing Irrigation Water 

Management. 

Progress: Reclamation provided $2,000,000 in funding to Colorado in the current 

agreement. $1,073,783 has been obligated in new BSP projects that when completed will 

result in salt control of 2,156 tons and treat and/or serve 611.5 acres at an average cost 

effectiveness of $51.37/ton. One wildlife-only project is planned for 2 acres of wildlife 

habitat replacement. Projects were competitively ranked through the NRCS EQIP 

ranking procedure in 2012. 

CSCRB is currently working with the Colorado Parks and Wildlife to fund approximately 

600 acres of wildlife improvements along the Colorado River in the Grand Valley for an 

estimated cost of about $800,000. The completion of this project would satisfy the 

remaining acres of habitat replacement required for the Grand Valley Salinity Unit. 

Paradox Valley Unit 

The Paradox Valley Unit was authorized for investigation and construction by the 

Salinity Control Act (Public Law 93-320) of 1974. The unit is located in southwestern 

Colorado along the Dolores River in the Paradox Valley, formed by a collapsed salt dome 

(Figure16). 

Groundwater in the valley comes into contact with the top of the salt formation where it
52 

becomes nearly saturated with sodium 

chloride. Salinities have been measured 

in excess of 250,000 mg/L, by far the 

most concentrated source of salt in the 

Colorado River Basin. Groundwater then 

surfaces in the Dolores River. 

The project continues to intercept and 

dispose of 100,000+ tons of salt annually 

(Figure 17). The pressure necessary to 

inject the brine into the disposal formation 

at 14,000 feet is increasing (Table 9). 

Modification of the facility to operate at a 

higher injection pressure to extend the life 

of the injection well was completed in 

2009, but at the current rate of injection 

pressure increase, the current maximum 

pressure limit could be reached in 3 to 5 

years or sooner. 

Seismicity associated with the injection 

process varies with the frequency and 

magnitude being relatively low (Table 9).

Modeling Salinity Without Paradox Unit 

The CRSS model was used to estimate the 

impacts to the Colorado River system if 

all the salt from the PVU were to enter the 

river in a without PVU scenario. In 

summary, by 2030 salinity would increase 

by 9-10 mg/L at all three numeric criteria 

sites in the lower Colorado River, with or 

without the plan of implementation. The 

probability of exceeding the numeric 

criteria increases by 3% for the “without 

additional controls” scenario and by about 

1 percent for the “with plan of 

implementation” scenario.

The CE-QUAL-W2 model of Lake 

Powell was used to assess the timing of increase in salinity below Glen Canyon Dam. If 

PVU ceased controlling salt then TDS would increase by 0.5 mg/L after one year, by 4.5 

mg/L after two, and by 7 to 10 mg/L thereafter. Similar modeling for Lake Mead and 

Hoover Dam was not completed but it was estimated to take approximately another two 

years for the full increase in concentration to be realized below Hoover Dam. If PVU 

operations ceased, it would take approximately 4 years to see the full effects in the Lower 

Basin. 

Figure 16 - Paradox Valley. 

Figure 17 - Schematic of Paradox Project. 

COLLECTION

WELLS

INJECTION

WELL

Dolores

River

SALINE GROUNDWATER

Paradox Valley Unit
53 

Table 9 - Paradox Well Injection Evaluation 

Injection Period

Operational 

Days1 Pressure 

Start

High 

Pressure 

During 

Period

Injection 

Period 

Net 

Pressure 

Change 

Tons of 

Salt 

Injected2

No. of 

Induced 

Seismic 

Events

Maximum 

Magnitude 

of Induced 

Seismic 

Events

Estimated 

Tons of 

Salt 

Entering 

the River3

Jan-May '024 148 1609 4432 52,860 25 2.9 8,469

June-Dec '025 178 929 4593 161 58,953 34 2.2 8,333

Jan-May '035 144 1172 4627 34 53,173 27 2.1 18,037

June-Dec '035 184 1154 4675 48 59,530 106 2.3 11,185

Jan-May '046 140 1201 4640 -35 51,449 47 2.4 20,225

June-Dec '047 160 1091 4541 -99 51,589 57 3.9 6,442

Jan-May '055 140 1038 4736 195 55,024 69 2.4 14,011

June-Dec '058 148 1203 4750 14 46,551 31 2.6 38,582

Jan-June '069 138 375 4680 -70 44,779 1010 2.4 53,039

July-Dec '065 162 1084 4797 117 56,920 1310 2.1 18,605

Jan-June '075 159 1066 4796 -1 56,068 710 1.1 19,728

July-Dec '075 163 1232 4712 -84 57,395 31 2.6 11,279

Jan-June '0811 160 1152 4813 101 54,720 47 1.3 15,305

July-Dec '085 162 1263 4822 9 56,734 61 2.1 16,378

*

Jan-Mar ‘095 84 1246 4756 -66 29,163 20 2.6 22,029

Apr-Sept '0912 160 1157 4891 135 55,083 70 2.7 16,507

Oct ‘09-Mar '105 153 970 4930 39 51,589 91 2.9 32,876

Apr ‘10-Sep '105 162 1347 4990 60 55,747 75 2.7 17,223

Oct ‘10-Mar '115 161 1378 5000 10 55,501 43 2.9 22,916 

Apr ‘11-Sep '1113 158 1276 5102 102 54,422 63 2.7 11,591 

Oct ’11-Mar ‘12 162 1282 5115 6 56,531 59 2.5 21,003 

Apr ’12-Sep ‘12 161 1417 5108 -7 55,605 116 1.9 5,507 

1. Operational days include partial days of operation which accounts for variations in tons of salt injected

2. Tons of salt injected based on 260,000 mg/L. Brine concentration varies slightly due to seasonal and environmental 

fluctuations

3. Tons of salt entering the river based on regression equations (Ken Watts, USGS Administrative Report – “Estimates of 

Dissolved Solids Load of the Dolores River in Paradox Valley, Montrose County, CO, 1988-2009, August 5, 2010”). The 

2010 FAR contained erroneous estimated tons of salt entering the river.

4. Begin 100% brine injection

5. No problems

6. Down from 3/1/04 through 3/7/04 for mechanical problems

7. Implemented quarterly 10-day shutdown schedule from 9/22 to 10/22; M3.9 earthquake on 11/7; plant shut down until 

11/18; discontinued 10-day shutdown schedule

8. Down from 11/13/05 through 12/31/05 for mechanical problems

9. Down from 1/1/06 through 1/19/06 and 2/16/06 through 3/2/06 for mechanical problems

10. Seismic data for 2006 and the first half of 2007 is likely incomplete due to seismic network problems

1. Down from 4/16-17/08 for mechanical problems

12. Down from 5/18-19/09 for mechanical problems 

13. Down from 9/18-9/20 for communication link failure. 

* Biannual shutdown schedule changed from winter/summer to spring/fall
54 

The effects of losing PVU in the Colorado River upstream of Lake Powell and in the 

Dolores River were examined using historic river concentrations and PVU injection 

rates. In the Dolores River reach from Paradox Valley downstream to the first significant 

tributary, San Miguel River, the increase in TDS was estimated to be over 700 mg/L (2x 

increase in TDS for this reach). From the Dolores River at its confluence with the San 

Miguel downstream to the Colorado River the increase is estimated to be 237 mg/L. The 

increase in the concentration of the Colorado River from the confluence with the Dolores 

River to the confluence with the Green River is estimated to be 20 mg/L. While the 

increases in TDS in the Dolores River are significant no current water quality standards 

in Colorado or Utah would be violated. 

Alternative Study 

In its definite plan report (September 1978), Reclamation recommended that a series of 

wells be drilled on both sides of the Dolores River to intercept the brine before it reached 

the river. The brine would then be pumped to an evaporation pond in Dry Creek Basin. 

A draft environmental statement was prepared for this plan and made public on May 11, 

1978; a final statement was filed with EPA on March 20, 1979. Due to the potential for 

environmental impacts, EPA recommended that Reclamation investigate deep-well 

injection as an alternative method of disposal. Now with potential issues with the salt 

injection well, this evaporation pond process is being reviewed. 

At the request of the Salinity Control Forum, Reclamation began exploring and 

development of a pilot study to evaluate evaporation ponds as a viable method for salt 

disposal at Paradox. In 2012, Reclamation continued to have meetings and discussion 

with the BLM, Service, EPA, and Colorado Department of Public Health and 

Environment. Major issues continue to be compliance with the Migratory Bird Treaty 

Act, permitting requirements for disposal of the brine evaporate and pond liner, and high 

levels of hydrogen sulfide. Initial cost estimates are dependent on site selection and 

environmental regulatory requirements. Reclamation continues to work to find a suitable 

site for the pilot study and refine cost estimates. Implementation of the pilot study is also 

dependent on obtaining a land withdrawal from BLM

Reclamation also began the process of beginning an alternative study/environmental 

impact statement for alternatives to replace the existing injection well. A Notice of Intent 

was published in the Federal Register on September 10, 2012 and public scoping 

meetings were held in Paradox, Montrose, and Grand Junction on September 25-27, 

2012. Reclamation will prepare a Scoping Summary Report for review in 2013. 

Colorado River Basin Salinity Control Program Summary Data 

The following tables summarize the salinity control program using the latest available 

data. 
55 

 Table 10 – Summary of Federal Salinity Control Programs (2012) 

Salinity Unit Tons / Year 

Removed 

MEASURES IN PLACE BY RECLAMATION 

Basinwide Program 206,600 

Basin States Program 1/ 12,200 

Meeker Dome 48,000 

Las Vegas Wash Pitman 3,800 

Grand Valley 122,300 

Paradox Valley 2/ 112,100 

Lower Gunnison Winter Water (USBR) 41,400 

Dolores 23,000 

Reclamation Subtotal 569,000 

MEASURES IN PLACE BY USDA/BSP 3/ 

Grand Valley 148,400 

Price-San Rafael 88,600 

Uinta Basin 149,700 

Big Sandy River 56,800 

Lower Gunnison 113,000 

McElmo Creek 29,300 

Mancos 4,300 

Muddy Creek 100 

Manila 81,000 

Silt 2,100 

Green River 200 

Tier 2 4 5,500 

 USDA/BSP Subtotal 601,000 

MEASURES IN PLACE BY BLM 

Nonpoint Sources 5/ 111,600 

Well-Plugging 14,600 

 BLM Subtotal 126,000 

Measures in Place Total 1,296,000 

GOALS TO REACH TARGET 

Reclamation Basinwide Program 336,900 

Price-San Rafael (USDA/BSP) 58,300 

Grand Valley (USDA/BSP) 6/ 0 

Uinta Basin (USDA/BSP) 7/ 7,600 

Big Sandy River (USDA/BSP) 26,900 

Lower Gunnison (USDA/BSP) 73,000 

McElmo Creek (USDA/BSP) 16,700 

Mancos River (USDA/BSP) 7,600 

Muddy Creek (USDA/BSP) 11,600 

Manila (USDA/BSP) 9,300 
56 

Silt (USDA/BSP) 6/ 1,900 

Green River (USDA/BSP) 6,400 

Tier 2 (USDA) 4/ 14,500 

New Well Plugging and Nonpoint Source (BLM) 0 

Goals Subtotal 571,000 

Target Total (Measures in Place + Goals) 1,867,000 

Target by 2030 1,850,000 

 

1/ Off-farm projects funded by Basin States Program 

2/ Paradox injection well capacity estimated to decline beginning in 2020; 

 assumed continuation of well or alternative control methods after 2020 3/ May include off-farm controls that were not goaled. 

4/ Measures in areas outside approved projects. 5/ BLM non-point source are estimates. 

6/ Original goal attained. 

7/ Estimated; original goal attained. 

 

 
57 

Table 11 – Summary of Colorado River Basin Salinity Control Program 

 Funding for Federal Agencies (In 1,000 Dollars) 

Federal 

Fiscal 

Year 

Bureau of 

Reclamation 

USDA -

NRCS 

Upfront Cost 

Sharing from 

Basin Funds1 

Bureau of 

Land 

Management2 Total 

 

1988 20,783 3,804 500 25,087 

1989 16,798 5,452 500 22,750 

1990 14,185 10,341 700 25,226 

1991 24,984 14,783 873 40,640 

1992 34,566 14,783 873 50,222 

1993 33,817 13,783 866 48,466 

1994 32,962 13,783 800 47,545 

1995 13,622 4,500 800 18,922 

1996 17,420 9,561 0 800 27,781 

1997 3,464 3,100 4,197 800 11,561 

1998 12,306 2,894 5,749 800 21,749 

1999 15,651 4,016 7,432 800 30,948 

2000 16,637 3,805 16,372 800 37,614 

2001 14,136 5,785 1,100 800 21,821 

2002 14,944 10,451 8,196 800 34,391 

2003 11,315 12,714 11,845 800 36,674 

2004 12,409 19,488 13,064 800 45,761 

2005 11,301 19,798 8,523 800 40,422 

2006 11,953 19,661 14,465 751 46,830 

2007 12,223 19,667 14,685 800 47,375 

2008 11,630 17,611 12,184 800 42,225 

2009 21,363 18,551 16,601 800 57,315 

2010 12,015 14,697 7,405 800 34,917 

2011 12,647 17,500 8,053 750 38,950 

2012 11,932 12,400 7,000 850 32,182 

1. Prior to 1996 Basin Funds were used to repay the reimbursable portion of Reclamation’s Salinity Control Projects 

within a fifty-year period or within a period equal to the estimated life of the project, whichever is less. 

2. Funds expended by BLM for salinity control cannot accurately be determined. This amount reflects what has been 

reported as having been designated within the BLM budget.
58 

Table 12 – Reclamation Salinity Control Unit Summary (P.L. 93-320 and 98-569) 

1. Cost per ton based on amortization over 50 years at the project authorized interest rate. 

Table 13 - UCRB Agriculture Salinity Control Summary (tons) - 2012 

Project Area Total Salt Load Total Ag. Load Total Controls Remaining Ag. Load 

Big Sandy 157,500 124,900 69,081 55,819

Grand Valley 580,000 559,100 276,154 282,946

Green River 15,700 15,700 178 15,522

Lower Gunnison 1,440,000 840,000 178,744 661,256

Mancos 43,000 26,000 4,325 21,675

Manila 49,000 40,000 13,548 26,452

McElmo 164,075 99,960 53,242 46,718

Muddy Creek 90,000 14,980 61 14,919

Price-San Rafael 430,000 244,000 139,463 104,537

Rifle - Silt NA 24,700 2,139 22,561

San Juan1 NA 62,530 48,329 14,201

Uinta 500,000 328,120 190,876 137,244

Paria (Tropic)1,2 NA 1,829 1,829 0

Tier 2-Unidentified3 NA NA 5,457

Total 3,469,275 2,381,819 983,426 1,403,850

1. Off-farm load shown only. On-farm loads have not been estimated for the San Juan and Paria areas 

2. Agricultural load for Paria only represents the conveyance systems which were piped as part of the Tropic 

Project 

3. Areas outside existing project boundaries. 

Unit/Study Implementation 

Controls 

(tons/y) 

Reclamation 

Capital Cost 

Annual 

O&M Costs 

Cost 

per Ton1 

Meeker Dome 1980-1983 48,000 $3,100,000 $0 $5 

Las Vegas Wash 1978-1985 3,800 $1,757,000 $0 $28 

Grand Valley 1980-1998 127,500 $160,900,000 $1,417,000 $83 

Paradox Valley 1988-1996 110,000 $66,199,000 $2,497,000 $60 

Dolores Project 1990-1996 23,000 $44,700,000 $613,000 $185 

Lower Gunnison 1991-1995 41,380 $24,000,000 $0 $35 

Total 353,680 $300,656,000 $4,016,000 $66 
59 

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Law, J.P., Jr., and A.G. Hornsby. 1982. The Colorado River Salinity Problem. Water 

Supply and Management, vol. 6, No. 1-2, pp. 87-104. 
66 

Liebermann, T.D., et al. 1987. User’s Manual for Estimation of Dissolved-Solids 

Concentrations and Loads in Surface Water. U.S. Geological Survey, Water Resources 

Investigations Report 86-4124. 

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Characteristics and Trends of Dissolved Solids in the Upper Colorado River Basin, 

Arizona, Colorado, New Mexico, Utah, and Wyoming. U.S. Geological Survey, 

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Army Corps of Engineers, Waterway Experiment Station, Contract 

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156 pp. 

Merritt, D. and Johnson, N. 1977. Advective Circulation in Lake Powell, Utah-Arizona. 

Lake Powell Research Project Bulletin No. 61, Institute of Geophysics and Planetary 

Physics, University of California, Los Angeles, California, 72 pp. 

Miffin, M.D. 1983. Reuse Versus Return Flows: Considerations for Selecting a Water 

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Moody, C.D., and D.K. Mueller. 1984. Water Quality of the Colorado System: 

Historical Trends in Concentration, Load, and Mass Fraction of Inorganic Solutes. 

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80-574. 
67 

Narayanan, R., and D.R. Franklin. 1982. An Evaluation of Water Conservancy 

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68 

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Colorado. 
69 

APPENDIX A 

SALINITY MONITORING STATION INFORMATION 

Figure A1 - Colorado River Water Quality Monitoring Stations.

1. Green River nr Green River, WY 

2. Green River nr Greendale, UT 

3. Yampa River nr Maybell, CO 

4. Duchesne River nr Randlett, UT 

5. White River nr Watson, UT 

6. Green River nr Green River, UT 

7. San Rafael River nr Green River, UT 

8. Colorado River nr Glenwood Springs, CO 

9. Colorado River nr Cameo, CO 

10. Gunnison River nr Grand Junction, CO 

11. Dolores River nr Cisco, UT 

12. Colorado River nr Cisco, UT 

13. San Juan River nr Archuleta, NM 

14. San Juan River nr Bluff, UT 

15. Colorado River @ Lees Ferry, AZ 

16. Colorado River nr Grand Canyon, AZ 

17. Virgin River @ Littlefield, AZ 

Numeric Criteria Stations 

18. Colorado River below Hoover Dam 

19. Colorado River below Parker Dam 

20. Colorado River @ Imperial Dam

1

2

3

4 

5

6

7 

8

9 

10 12 11 

13

14

15 

16 

17

18 

19 

20 

Monitoring Stations 
70 

Table A1. Characteristics of the 20 Salinity Streamflow‐gaging Stations in the Colorado River Basin.  

[NA, indicates not applicable; Latitude and Longitude datum: NAD83; Elevation datum: NGVD29.]

U.S.

Geological

Survey

streamflow‐

gaging

station

number

U.S. Geological Survey streamflow‐gaging

station name

Site

short

name

Latitude,

in decimal

degrees

Longitude,

in decimal

degrees

Elevation,

in feet

above

sea level

Drainage

area, in

square

miles

09217000 Green River near Green River WY GRWY 39.5589  ‐107.2909 5,760 4,556

09234500 Green River near Greendale, UT GDALE 39.2391  ‐108.2662 4,814 7,986

09251000 Yampa River near Maybell, CO YAMPA 38.9833  ‐108.4506 4,628 7,923

09302000 Duchesne River near Randlett, UT DUCH 38.7972  ‐109.1951 4,165 4,580

09306500 White River near Watson, UT WHITE 38.8105  ‐109.2934 4,090 24,100

09315000 Green River at Green River, UT GRUT 41.5164  ‐109.4490 6,060 14,000

09328500 San Rafael River near Green River, UT SANRAF 40.9083  ‐109.4229 5,594 19,350

09071750 Colorado River above Glenwood Springs, CO GLEN 40.5027  ‐108.0334 5,900 3,383

09095500 Colorado River near Cameo, CO CAMEO 40.2103  ‐109.7814 4,756 3,790

09152500 Gunnison River near Grand Junction, CO GUNN 39.9789  ‐109.1787 4,947 4,020

09180000 Dolores River near Cisco, UT DOLOR 38.9861  ‐110.1512 4,040 44,850

09180500 Colorado River near Cisco, UT CISCO 38.8583  ‐110.3701 4,190 1,628

09355500 San Juan River near Archuleta, NM ARCH 36.8019  ‐107.6986 5,653 3,260

09379500 San Juan River near Bluff, UT BLUFF 37.1469  ‐109.8648 4,048 23,000

09380000 Colorado River at Lees Ferry, AZ LEES 36.8647  ‐111.5882 3,106 111,800

09402500 Colorado River near Grand Canyon, AZ GRCAN 36.1014  ‐112.0863 2,419 141,600

09415000 Virgin River at Littlefield, AZ VIRGIN 36.8916  ‐113.9244 1,764 5,090

09421500 Colorado River below Hoover Dam, AZ‐NV HOOVER 36.0153  ‐114.7386 675 171,700

09427520 Colorado River below Parker Dam, AZ‐CA PARKER 34.2956  ‐114.1402 301 182,700

09429490 Colorado River above Imperial Dam, AZ‐CA IMPER 32.8837  ‐114.4674 183 188,500
71 

Figure A2 – Colorado River Flow and Salinity 
72 
73 

APPENDIX B 

SALT LOAD 2012 UPDATE FOR THE 20 STATIONS

(Updates calendar years 2008 through 2011) 

STATION CLASSIFICATIONS 

U.S. Geological Survey 

Colorado Water Science Center 

Western Colorado Office 

September 17, 2012
74 

INTRODUCTION 

Methodology 

Three Statistical Analyses System (SAS) computer programs, FLAGIT, DVCOND, and 

SLOAD are use to estimate dissolved-solids concentrations and loads from existing data. 

The program FLAGIT retrieves data from the daily-values (DV) file and water-quality 

file (QW) of the U.S. Geological Survey's National Water Data Storage and Retrieval 

System (WATSTORE) (Hutchinson, 1975), examines the data, deletes incomplete 

observations, and flags possible errors in the remaining observations. FLAGIT also 

produces the data base used by the programs DVCOND and SLOAD. The program 

DVCOND fills in missing values in the daily specific-conductance record by linear 

interpolation. DVCOND needs to be used only when the flow at a streamflow-gaging 

station is extensively regulated. 

The program SLOAD derives regression relations from water-quality data, modeling 

dissolved solids and six major ions as functions of specific conductance and discharge 

(Q). SLOAD then applies these relations to the daily specific conductance and discharge 

data and computes daily loads of dissolved solids and the other six major ions. The 

computed daily loads are summed by month and by year. Monthly and annual dissolvedsolids and major ion concentrations are computed from the monthly and annual loads and 

streamflows. Monthly, annual, and seasonal concentrations and loads, in addition to 

regression statistics, are printed and saved on SAS data sets. Separate versions of 

SLOAD enable annual summation either by water year (WY) or calendar year (CY) 

(Lieberman and others, 1987). 

The computerized method can be used for streamflow-gaging stations that have a 

complete record of DV Q and periodic QW analyses. The reliability of the estimate is 

considerably increased if DV specific conductance (SC) also is available. Water-quality 

analysis that includes total dissolved solids (TDS) with major ion analysis (also referred 

to as sum of constituents or SOC/SUM; herein referred to as SOC) is preferred over 

residue on evaporation at 180 degrees Celsius (ROE). SOC enables SLOAD calculations 

of the 8 major constituents normally present in natural streams: Calcium (Ca2+), 

magnesium (Mg2+), sodium (Na+), potassium (K+), silica (Si), chloride (Cl-), sulfate 

(SO4

2-), and carbon, expressed as carbonate equivalent (Liebermann and others, 1987). 

Classification Criteria 

The 20 stations are classified A, B, or C, according to the quantity and quality of 

available data for the salt-load computations. Optimal data collection at each station 

includes daily mean streamflow, daily mean SC, and at least 6 water quality samples per 

WY which include TDS. SC may be monitored continuously with an instrument (daily 

mean) or sampled once per day by an observer (instantaneous). Continuous monitoring 

for daily mean SC by instrument is the preferred method. 
75 

Types of Specific Conductivity 

Specific Conductivity at the sites is classified into several types: 

 Daily – mean daily SC collected by instrumentation. To be considered “daily”, 

the record may have up to 60 missing days of SC per water year which are spread 

out in small groups over the year. 

 Intermittent – mean daily SC which has more than 60 missing days per water year 

spread out over the water year. 

 Seasonal – mean daily SC has been continuously shut off during the winter 

(November through March typically), with more than 60 missing days. 

 Instantaneous – single SC values which have been manually collected by an 

observer. Usually spaced several days apart, and may be missing during winter 

months. 

CLASS A 

For Class A, adequate data must be available for salt-load computation using SLOAD. 

Site data includes: 

 6 or more QW samples per WY which include some type of TDS (ROE, SOC, or 

Calculated). SLOAD automatically discards QW records without any type of 

TDS. 

 Daily Q (SLOAD allows no days with missing Q). 

 Mean daily SC from instrumentation. The SC record must be “daily”, and must 

have no more than 60 total days of missing values for the WY.

CLASS B 

Salt-load computation is possible using SLOAD, but limited data availability could be 

contributing to error in salt load estimate. Even though the site has daily Q and daily SC, 

if there are fewer than 6 QW observations, the site will be Class B. Site data includes: 

 There are fewer than 6 QW samples per WY which include some type of TDS. 

 Daily Q (SLOAD allows no days with missing Q). Missing Q values may be 

interpolated from surrounding values. 

 SC may be mean daily (with up to 60 missing days), seasonal, intermittent (more 

than 60 missing days), instantaneous from observers, or non-existant. 

CLASS C 

Inadequate data exists for SLOAD salt-load computation. Site data includes: 

 Some QW records may exist, but none have TDS, hence they are not usable. 

 SC may or may not exist, but is not used. 

 Salt concentration and load are calculated from regression analysis of old data (Q 

and TDS). 
76 

Improvements and Declines in Class 

The classification is shown by year for each site in the tables. This is helpful to see the 

trend in classifications. 

A judgment call must be made for the final year classification. The final year has 

incomplete data, and the data have not been finalized by USGS. The final year 

classification will be shown as “provisional” if the criteria for the class are being met as 

of the cutoff date for the data. For example, if sufficient QW records exist to suggest that 

6 observations will be made by the end of the WY, and if daily SC is being recorded, then 

A (provisional) will be given. The pattern of QW observations for the previous years is 

taken to project the QW for the final year. The final year will not be shown as provisional 

if no daily SC is being recorded, (the class is clearly B), or, if no QW records are 

available, (the class is clearly C). 

#1 GRWY - STATION 09217000 Green River near Green River, WY 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

9 12 12 12 7 (thru 4‐20)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Seasonal (144

missing)

Seasonal (124

missing)

Seasonal (118

missing)

Seasonal (136

missing)

Seasonal (127

missing)

TDS Method 9 ROE & SOC

pairs (3 SOC

missing)

12 ROE & SOC

pairs (0 missing)

12 ROE & SOC

pairs (0 missing)

12 ROE and SOC

pairs (1 SOC

missing)

7 ROE and SOC

pairs (0 missing)

Class by Year B B B B B (provisional)

Notes Missing SC >

60/yr

Missing SC >

60/yr

Missing SC >

60/yr

Missing SC >

60/yr

Missing SC > 60/yr

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding sources: USGS NSIP $15,900

(streamflow), SC and period QW monitoring funding through Wyoming Landscape Conservancy Initiative –

the amount and whether any of this funding is matched by USGS CWP funding has not been reported from

Wyoming WSC yet.
77 

#2 GDALE - STATION 09234500, Green River near Greendale, UT 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

0 0 0 0 0

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method None None None None None

Class by Year C C C C C

Notes No QW, No

TDS

No QW, No TDS No QW, No TDS No QW, No TDS No QW, No TDS

Daily Q only, no SC, no QW with TDS. Water quality data ended 08/30/2000. Due to insufficient data,

SLOAD computations cannot be run for this station. Salt loads were calculated using a linear regression

equation derived from old Q and TDS data (1/1990 through 8/2000.)   

Operation is by USGS for daily Q.  2012 Funding Sources: USGS NSIP ‐ $15,600 (streamflow), Continuous SC

is monitored at the dam, upstream of the gage by USBR. In FY2013 USBR restarted funding for USGS to

operate continuous SC at this gage.   

#3 YAMPA – STATION 09251000, Yampa River near Maybell, CO    

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

8 6 6 6 3 (thru 3‐26)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Daily (1 missing) Daily (13

missing)

Daily (44

missing)

Daily (34

missing)

Daily (11 missing)

TDS Method 8 SOC (0

missing)  

6 SOC (0

missing)

6 SOC (0

missing)

6 SOC (0

missing)

3 SOC (0 missing)

Class by Year A A A A A (provisional)

Notes Missing SC < 60

/ yr

Missing SC < 60

/ yr

Missing SC < 60

/ yr

Missing SC < 60

/ yr

Missing SC < 60 /

yr

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $16,200

(streamflow), USGS CWP ‐ $9,130 (QW), Col. Riv. Water District ‐ $15,890 (QW), Local cooperator TDS

Program ‐ $1,420 (QW).
78 

#4 DUCH – STATION 09302000, Duchesne River near Randlett, UT 

Note class improvement for 2009.

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

9 11 8 8 5 (thru 4/10 )

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC No (366

missing)

Daily (23

missing)

Daily (5 missing) Daily (59

missing)

Daily (0 missing)

TDS Method 9 SOC (0

missing)

9 SOC (2

missing)

8 ROE & SOC

pairs (2 ROE

missing)

8 ROE & SOC

pairs (0 missing)

5 ROE & SOC pairs

(0 missing)

Class by Year B A A A A (provisional)

Notes Missing SC > 60

/ yr

Missing SC < 60

/ yr

Missing SC < 60

/ yr

Missing SC < 60

/ yr

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS CWP ‐ $7,020

(streamflow), USGS CWP ‐ $1,160 (QW), USBR ‐ $14,770 (QW), Central Utah Water Con. District ‐ $8,580

(streamflow), $1,420 (QW).  

#5 WHITE – STATION 09306500, White River near Watson, Utah 

Note decline number of QW samples in 2009‐10.

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

8 8 8 8 6

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method 6 ROE and 2

SOC (0 missing)

1 ROE & SOC

pair, 7 SOC (0

missing)

8 ROE & SOC

pairs (0 missing)

8 ROE & SOC

pairs (0 missing)

6 ROE & SOC pairs

(0 missing)

Class by Year B B B B B (provisional)

Notes       

Operation is by USGS for daily Q and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $15,600

(Streamflow), USBR ‐ $4,800 (QW).  
79 

#6 GRUT – STATION 09315000, Green River at Green River, UT 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

8 8 8 9 3 (thru 5/29)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None Partial (1/1 thru

3/31) from

observer

TDS Method 8 SOC (0

missing)

1 ROE & SOC

pair, 7 SOC (0

missing)

8 ROE & SOC

pairs (0 missing)

9 ROE & SOC

pairs (0 missing)

3 SOC (0 missing)

Class by Year B B B B B (provisional)

Notes       

Operation is by USGS for daily Q and periodic QW.  For SC, a sample bottle  is collected once a day by an

observer, and is measured in 30 day batches at the Moab office using a YSI handheld probe. 2012 Funding

Sources: USGS NSIP ‐ $15,600 (streamflow), USBR ‐ $17,350.  

#7 SANRAF – STATION 09328500, San Rafael River near Green River, UT 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

6 8 8 9 4 (thru 6/06)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method 6 SOC (0

missing)

1 ROE & SOC

pair, 6 SOC (0

missing)

7 ROE & SOC

pairs, 1 ROE (0

missing)

9 ROE & SOC

pairs (0 missing)

4 ROE & SOC pairs

(0 missing)

Class by Year B B B B B (provisional)

Notes       

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $15,600,

USBR ‐ $17,350 (QW)
80 

#8 GLEN – STATION 09071750, Colorado River above Glenwood Springs, 

CO 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

8 6 6 6 4 (thru 6/7)

Daily Q Estimated (0

missing)

Estimated (0

missing)

Estimated (0

missing)

Estimated (0

missing)

Estimated (0

missing)

SC Daily (6 missing) Daily (15

missing)

Daily (32

missing)

Daily (15

missing)

Daily (2 missing)

TDS Method 8 SOC (0

missing)

6 SOC (0

missing)

6 SOC (0

missing)

6 SOC (0

missing)

4 SOC (0 missing)

Class by Year A A A A A (provisional)

Notes       

This station has an SC monitor but no stream gage. Flow is computed as the difference between station

09085100 (Colorado River below Glenwood Springs, CO) and station 09085000 (Roaring Fork River at

Glenwood Springs, CO).  

Operation is by USGS for estimated Q, daily SC and periodic QW.  2012 Funding Sources: USGS NSIP ‐ 

$32,400 (streamflow), USBR ‐ $24,360 (QW).

#9 CAMEO - STATION 09095500, Colorado River near Cameo, CO 

Water Year 2008 2009 2010 2011 2012 (thru 6‐

10)

QW

Observations

5 5 4 5 3 (thru 5/09)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Daily (0 missing) Daily (36

missing)

Daily (34

missing)

Daily (38

missing)

Daily (25 missing)

TDS Method 5 SOC (0

missing)

5 SOC (0

missing)

4 SOC (0

missing)

5 SOC (0

missing)

3 SOC (0 missing)

Class by Year B B B B B (provisional)

Notes QW

observations < 6

QW

observations < 6

QW

observations < 6

QW

observations < 6

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $16,200,

USGS CWP ‐ $1,150 (QW), Col.Water Riv. District ‐ $1,993 (QW), USBR ‐ $23,480 (QW).  
81 

#10 GUNN - STATION 09152500, Gunnison River near Grand Junction, CO 

Note improvement in class for 2011.

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

5 5 5 7 5 (thru 5/258)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Intermittant (68

missing)

Daily (6

missing)

Daily (9

missing)

Daily (37

missing)

Daily (1 missing)

TDS Method 5 SOC (0 missing) 5 SOC (0

missing)

5 SOC (0

missing)

7 SOC (0

missing)

5 SOC (0 missing)

Class by Year B B B A A (provisional)

Notes      QW samples > 6   

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding  Sources: USGS NSIP ‐ $16,200

(streamflow), USGS CWP ‐ $1,150 (QW), Col. Riv. Water District ‐ $1,993 (QW), USBR ‐ $31,860 (QW).  

#11 DOLOR - STATION 09180000, Dolores River near Cisco, UT 

Note improvement in class after 2008.

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

8 9 8 8 5 (thru 5‐14)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Intermittent (64

missing)

Daily (13

missing)

Daily (12

missing)

Daily (29

missing)

Daily (4 missing)

TDS Method 8 SOC (0 missing)   7 SOC, 2 ROE &

SOC pairs (0

missing)

8 ROE & SOC

pairs (1 SOC

missing)

8 ROE & SOC

pairs (0 missing)

5 ROE & SOC pairs

(0 missing)

Class by Year B A A A A (provisional)

Notes SC missing > 60        

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $15,600

(streamflow), USBR ‐ $17,350 (QW).  
82 

#12 CISCO - STATION 09180500, Colorado River near Cisco, UT 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

6 9 8 8 4 (thru 5/16)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Daily (26

missing)

Daily (7 missing) Daily (13

missing)

Daily (2 missing) Daily (7 missing)

TDS Method 6 SOC (0

missing)

7 SOC, 2 ROE &

SOC pairs (0

missing)

8 ROE & SOC

pairs (1 ROE

missing)

8 ROE & SOC

pairs (0 missing)

4 ROE & SOC pairs

(0 missing)

Class by Year A A A A A (provisional)

Notes       

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $15,600

(streamflow), USBR ‐ $17,350 (QW).  

#13 ARCH - STATION 09355500, San Juan River near Archuleta, NM 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

0 4 3 3 2

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method None 3 ROE & SOC

pairs, 1 SOC  (0

missing)

2 ROE, 1 ROE &

SOC pair (0

missing)

1 ROE, 2 ROE &

SOC pairs (0

missing)

1 ROE, 1 ROE &

SOC pair (0

missing)

Class by Year C B B B B (provisional)

Notes       

Due to insufficient data SLOAD computations cannot be run for this station. Salt loads were calculated

using a linear regression equation derived from old Q and TDS data (1/1990 through 7/2007.)  Due to

improvements in QW observations starting in 2009, it may be possible to use SLOAD for the update in

2014.

Operation is by USGS for daily Q and periodic QW.  2012 Funding Sources: USGS CWP $7,218 (streamflow),

USGS CWP $2,780 (QW), NM Interstate Stream Comm. ‐ $13,062 (streamflow), NM Dept. of Ag ‐ $$2780

(QW), USBR ‐ $11,620 (QW).
83 

#14 BLUFF - STATION 09379500, San Juan River near Bluff, UT 

Note class improvement starting in 2009.

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

8 8 9 9 5 (thru 5/30)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Intermittant (70

missing)

Daily (12 missing) Daily (9

missing)

Daily (6

missing)

Daily (2 missing)

TDS Method 8 SOC (0 missing) 6 SOC, 2 ROE &

SOC pairs (0

missing)

9 ROE & SOC

pairs (0

missing)

9 ROE & SOC

pairs (0

missing)

5 ROE & SOC pairs

(0 missing)

Class by Year B A A A A (provisional)

Notes Class

improvement

    

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $15,600

(streamflow), $17,350 (QW)

#15 LEES - STATION 09380000, Colorado River at Lees Ferry, AZ 

Water Year 2008 2009 2010 2011 2012 (thru 6‐

10)

QW

Observations

4 4 4 4 3 (thru 2‐14)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Daily (0 missing) Daily (23

missing)

Daily (16

missing)

Daily (0 missing) Daily (2 missing)

TDS Method 4 ROE & SOC

pairs (0 missing)

4 ROE & SOC

pairs (0 missing)

4 ROE & SOC

pairs (0 missing)

4 ROE & SOC

pairs (0 missing)

2 ROE & SOC

pairs, 1 SOC (0

missing)

Class by Year B B B B B (provisional)

Notes QW

observations < 6

QW

observations < 6

QW

observations < 6

QW

observations < 6

Operation is by USGS for daily Q, daily SC, and periodic QW.  2012 Funding Sources: USGS NSIP ‐ $15,000

(streamflow), USBR‐Boulder ‐ $2,700 (streamflow), USBR/GCMRC ‐ $15,000 (QW)
84 

#16 GRCAN - STATION 09402500, Colorado River near Grand Canyon, AZ 

Water Year 2008 2009 2010 2011 2012 (thru 6‐

10)

QW

Observations

None None None None None

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method None None None None None

Class by Year C C C C C

Notes      

Daily Q only, no SC. There has been no water quality sampling since late 1980’s. Salt loads are computed

with a special version of SLOAD by using the load at station 09380000 (Colorado River at Lees Ferry, AZ)

and the flow difference between the 2 stations.  

Operation is by USGS for daily Q.  2012 Funding Sources: USBR Boulder ‐ $23,700 (streamflow), USBR

GCMRC ‐ $$4,100 (streamflow).  

#17 VIRGIN - STATION 09415000, Virgin River at Littlefield, AZ 

Water Year 2008 2009 2010 2011 2012 (thru 6‐

10)

QW

Observations

4 4 2 4 2 (thru 3‐15)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method 4 ROE & SOC

pairs (0 missing)

4 ROE & SOC

pairs (0 missing)

2 ROE & SOC

pairs (0 missing)

4 ROE & SOC

pairs (0 missing)

2 ROE & SOC

pairs (0 missing)

Class by Year B B B B B (provisional)

Notes QC observations

< 6

QC observations

< 6

QC observations

< 6

QC observations

< 6

Operation is by USGS for daily Q and periodic QW.  2012 Funding Sources: USGS CWP ‐ $10,800

(streamflow), USGS CWP ‐ $18,600 (QW), Southern Nevada Water Authority ‐ $10,800 (streamflow),

Southern Nevada Water Authority ‐ $18,600 (QW). (Operated by USGS Nevada WSC)
85 

#18 HOOVER – STATION 09421500, Colorado River below Hoover Dam, AZNV 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

14 14 12 15 10 (thru 5/23)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Daily (1 missing) Daily (0 missing) Daily (3 missing) Daily (11

missing)

Daily (51 missing)

TDS Method 13 ROE & SOC

pairs. 1 ROE (0

missing)

14 ROE & SOC

pairs (0 missing)

12 ROE & SOC

pairs (0 missing)

15 ROE & SOC

pairs (0 missing)

10 ROE & SOC

pairs (0 missing)

Class by Year A A A A A (provisional)

Notes Incl BOR data Incl BOR data Incl BOR data Incl BOR data Incl BOR data

Operation is by USGS for daily Q and periodic QW and by BOR for daily SC and periodic QW.  2012 Funding

Sources: USGS CWP ‐ $18,900 (QW), Southern Nevada Water Authority ‐ $18,900 (QW).  

#19 PARKER - STATION 09427520, Colorado River below Parker Dam, AZCA 

Water Year 2008 2009 2010 2011 2012 (thru 6‐

10)

QW

Observations

28 24 29 28 18 (thru 5/21)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC None None None None None

TDS Method 28 ROE & SOC

pairs (0 missing)

24 ROE & SOC

pairs (0 missing)

29 ROE & SOC

pairs (0 missing)

28 ROE & SOC

pairs (0 missing)

18 ROE & SOC

pairs (0 missing)

Class by Year B B B B B

Notes Incl BOR data Incl BOR data Incl BOR data Incl BOR data Incl BOR data

Operation is by USGS for daily Q and periodic QW and by BOR for periodic SC and periodic QW.  2012

Funding Source: USGS NSIP ‐ $15,310 (streamflow), Metropolitin Water ‐ $1,140 (streamflow, AZ DEQ ‐ 

$10,000 (QW)  
86 

#20 IMPER - STATION 09429490, Colorado River above Imperial Dam, AZCA 

Water Year 2008 2009 2010 2011 2012 (thru 6‐10)

QW

Observations

36 56 30 27 18 (thru 6/4)

Daily Q Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing) Yes (0 missing)

SC Daily (0 missing) Daily (0 missing) Daily (0 missing) Daily (0 missing) Daily (0 missing)

TDS Method 14 ROE & SOC

pairs, 22 ROE (0

missing)

4 ROE & SOC

pairs, 52 ROE (0

missing)

4 ROE & SOC

pairs, 26 ROE (0

missing)

4 ROE & SOC

pairs, 23 ROE (0

missing)

2 ROE & SOC

pairs, 16 ROE (0

missing)

Class by Year A A A A A (provisional)

Notes Incl BOR data Incl BOR data Incl BOR data Incl BOR data Incl BOR data

Operation is by USGS for daily Q and quarterly QW and by BOR for daily SC and additional QW.  2012

Funding Sources: USGS NSIP ‐ $16,450  (streamflow).

References 

Liebermann, T.D., Middelburg, R.F., Irvine, S.A. 1987. User’s Manual for Estimation of 

Dissolved-Solids Concentrations and Loads in Surface Water. U.S. Geological Survey, 

Water Resources Investigations Report 86-4124. 
87 

1. STATION 09217000 (GRWY) Green River near Green River, WY 

 STATION 09217000 Green River near Green River, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 33 9.1 0.0

2 2009 33 9.1 0.0

3 2010 36 2.8 0.0

4 2011 31 3.2 0.0

5 2012 31 3.2 0.0

 

STATION 09217000 Green River near Green River, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 33 0.89785 0.13462 1.85800 0.69252 30 0.99292 0.03788 -7.1797 0.97862 1.15325

2 Calcium 30 0.33606 0.13381 4.98663 -0.16617 27 0.81674 0.07287 -2.4239 0.06838 0.94480

3 Magnesium 30 0.51084 0.12572 4.29890 -0.22426 27 0.90736 0.05754 -3.1614 0.01044 0.95319

4 Chloride 30 0.48740 0.22210 4.04927 -0.37803 27 0.96462 0.06214 -10.1318 0.06328 1.81960

5 Sulfate 30 0.68508 0.20801 8.23544 -0.53553 27 0.98289 0.05171 -5.2378 -0.11599 1.72819

6 Carbonate 30 0.47489 0.08370 5.41086 -0.13893 27 0.84104 0.04827 0.8108 0.00619 0.58714

7 Sodium +K 30 0.73587 0.15896 6.59458 -0.46313 27 0.92803 0.08882 -2.3095 -0.18832 1.14604

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 33 0.89785 0.13462 1.85800 0.69252 30 0.99292 0.03788 -7.1797 0.97862 1.15325

9 Calcium 30 0.33606 0.13381 4.98663 -0.16617 27 0.81674 0.07287 -2.4239 0.06838 0.94480

10 Magnesium 30 0.51084 0.12572 4.29890 -0.22426 27 0.90736 0.05754 -3.1614 0.01044 0.95319

11 Chloride 30 0.48740 0.22210 4.04927 -0.37803 27 0.96462 0.06214 -10.1318 0.06328 1.81960

12 Sulfate 30 0.68508 0.20801 8.23544 -0.53553 27 0.98289 0.05171 -5.2378 -0.11599 1.72819

13 Carbonate 30 0.47489 0.08370 5.41086 -0.13893 27 0.84104 0.04827 0.8108 0.00619 0.58714

14 Sodium +K 30 0.73587 0.15896 6.59458 -0.46313 27 0.92803 0.08882 -2.3095 -0.18832 1.14604
88 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 36 0.89182 0.15724 1.36254 0.76702 33 0.99618 0.03119 -6.8111 0.98028 1.09061

16 Calcium 35 0.17748 0.15788 4.71935 -0.12312 32 0.87232 0.06509 -2.8640 0.07927 1.00535

17 Magnesium 35 0.32865 0.14498 3.96911 -0.17029 32 0.93188 0.04878 -3.2575 0.02054 0.96090

18 Chloride 35 0.31647 0.27269 3.66785 -0.31150 32 0.88851 0.11674 -9.3013 0.02551 1.73256

19 Sulfate 35 0.59617 0.22808 7.78828 -0.46522 32 0.97390 0.06128 -3.7854 -0.16182 1.54229

20 Carbonate 35 0.20336 0.11161 5.13144 -0.09466 32 0.84664 0.05175 -0.1445 0.04496 0.70110

21 Sodium +K 35 0.63575 0.18636 6.29213 -0.41331 32 0.92185 0.09149 -2.1923 -0.19488 1.13645

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 31 0.80230 0.15724 1.34406 0.77395 30 0.99396 0.02843 -6.7762 0.97039 1.09654

23 Calcium 30 0.09040 0.15738 4.72263 -0.11958 29 0.89010 0.05676 -3.0205 0.07221 1.03958

24 Magnesium 30 0.22283 0.13700 4.06372 -0.17680 29 0.94222 0.03877 -2.8493 -0.00578 0.92847

25 Chloride 30 0.20532 0.26875 3.85198 -0.32922 29 0.86117 0.11613 -8.8215 -0.01827 1.70591

26 Sulfate 30 0.42414 0.22941 7.89247 -0.47448 29 0.96073 0.06216 -3.6893 -0.18891 1.55689

27 Carbonate 30 0.04407 0.10963 4.88576 -0.05673 29 0.82796 0.04823 -0.3243 0.07256 0.69913

28 Sodium +K 30 0.46087 0.19617 6.48632 -0.43710 29 0.85790 0.10388 -2.1022 -0.22777 1.15812

2. STATION 09234500 (GDALE) Green River Near Greendale, UT, NO 

REGRESSION STATS 

This site has daily Q only and no daily SC. Water quality sampling ended on 08/30/2000. 

Insufficient data for SLOAD computations. Salt loads were calculated using a linear 

regression equation derived from old data (01/1990 through 08/2000.) See spreadsheet 

gdale12regression.xlsx 
89 

3. STATION 09251000 (YAMPA) Yampa River near Maybell, CO

STATION 09251000 Yampa River near Maybell, CO UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 20 0.0 0.0

2 2009 20 0.0 0.0

3 2010 18 0.0 0.0

4 2011 15 0.0 0.0

5 2012 15 0.0 0.0

STATION 09251000 Yampa River near Maybell, CO UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 20 0.76611 0.51679 1.47379 0.72421 20 0.99858 0.04140 -7.05775 1.00882 1.09444

2 Calcium 20 0.33679 0.37483 4.91773 -0.20683 20 0.97866 0.06919 -1.18846 -0.00313 0.78331

3 Magnesium 20 0.29171 0.56153 4.72305 -0.27904 20 0.99498 0.04866 -4.54243 0.03005 1.18859

4 Chloride 20 0.65542 0.49871 5.81078 -0.53257 20 0.98341 0.11258 -2.24616 -0.26380 1.03355

5 Sulfate 20 0.23324 0.72612 6.53417 -0.31010 20 0.98916 0.08882 -5.40446 0.08817 1.53150

6 Carbonate 20 0.56138 0.29723 5.90401 -0.26038 20 0.96554 0.08572 1.17935 -0.10277 0.60609

7 Sodium +K 20 0.45151 0.58042 6.13109 -0.40777 20 0.99177 0.07315 -3.40775 -0.08955 1.22365

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 20 0.76611 0.51679 1.47379 0.72421 20 0.99858 0.04140 -7.05775 1.00882 1.09444

9 Calcium 20 0.33679 0.37483 4.91773 -0.20683 20 0.97866 0.06919 -1.18846 -0.00313 0.78331

10 Magnesium 20 0.29171 0.56153 4.72305 -0.27904 20 0.99498 0.04866 -4.54243 0.03005 1.18859

11 Chloride 20 0.65542 0.49871 5.81078 -0.53257 20 0.98341 0.11258 -2.24616 -0.26380 1.03355

12 Sulfate 20 0.23324 0.72612 6.53417 -0.31010 20 0.98916 0.08882 -5.40446 0.08817 1.53150

13 Carbonate 20 0.56138 0.29723 5.90401 -0.26038 20 0.96554 0.08572 1.17935 -0.10277 0.60609

14 Sodium +K 20 0.45151 0.58042 6.13109 -0.40777 20 0.99177 0.07315 -3.40775 -0.08955 1.22365
90 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 18 0.84945 0.39546 1.15001 0.77740 18 0.99895 0.03411 -7.31909 1.02027 1.12566

16 Calcium 18 0.32720 0.28539 4.67261 -0.16471 18 0.97454 0.05734 -1.34360 0.00783 0.79964

17 Magnesium 18 0.25815 0.43141 4.32099 -0.21061 18 0.98988 0.05205 -4.88703 0.05346 1.22387

18 Chloride 18 0.72764 0.34879 5.41399 -0.47180 18 0.98544 0.08329 -1.87875 -0.26266 0.96931

19 Sulfate 18 0.19921 0.56924 6.08418 -0.23496 18 0.98448 0.08184 -6.03030 0.11245 1.61018

20 Carbonate 18 0.53521 0.23631 5.60494 -0.20986 18 0.92485 0.09814 0.95505 -0.07651 0.61804

21 Sodium +K 18 0.48516 0.42440 5.67621 -0.34095 18 0.98493 0.07500 -3.31016 -0.08324 1.19441

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 15 0.90449 0.33536 0.76352 0.84345 15 0.99894 0.03675 -7.37448 1.02049 1.13459

23 Calcium 15 0.23745 0.23995 4.36738 -0.10943 15 0.92373 0.07899 -1.18739 0.01140 0.77444

24 Magnesium 15 0.18515 0.36694 3.94035 -0.14296 15 0.98195 0.05684 -4.91420 0.04966 1.23449

25 Chloride 15 0.73148 0.30287 5.03278 -0.40856 15 0.98280 0.07979 -2.11735 -0.25302 0.99686

26 Sulfate 15 0.11146 0.48962 5.53251 -0.14173 15 0.97137 0.09147 -6.22141 0.11396 1.63872

27 Carbonate 15 0.48433 0.20185 5.32293 -0.15988 15 0.83713 0.11807 1.24885 -0.07125 0.56800

28 Sodium +K 15 0.45283 0.36058 5.21474 -0.26810 15 0.98937 0.05231 -3.49846 -0.07855 1.21478

4. STATION 09302000 (DUCH) Duchesne River near Randlett, UT 

 

STATION 09302000 Duchesne River near Randlett, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 26 0.0 0.0

2 2009 26 0.0 0.0

3 2010 25 0.0 0.0

4 2011 21 0.0 0.0

5 2012 21 0.0 0.0

STATION 09302000 Duchesne River near Randlett, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
91 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 26 0.82713 0.27536 2.85264 0.57299 25 0.99421 0.05010 -6.99656 1.01850 1.08150

2 Calcium 26 0.68560 0.22528 5.95298 -0.31648 25 0.97407 0.06753 -1.79775 0.03286 0.85222

3 Magnesium 26 0.66871 0.30175 5.87296 -0.40783 25 0.98129 0.07473 -4.89976 0.08147 1.18107

4 Chloride 26 0.78301 0.30361 6.53177 -0.54864 25 0.96435 0.12810 -3.46286 -0.09789 1.09869

5 Sulfate 26 0.70815 0.34748 8.30186 -0.51490 25 0.98832 0.07242 -4.15904 0.05022 1.36695

6 Carbonate 26 0.65480 0.20412 6.35715 -0.26744 25 0.91030 0.10854 -0.00349 0.01996 0.69872

7 Sodium +K 26 0.76147 0.31080 7.37390 -0.52826 25 0.97667 0.10126 -3.29603 -0.04645 1.17237

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 26 0.82713 0.27536 2.85264 0.57299 25 0.99421 0.05010 -6.99656 1.01850 1.08150

9 Calcium 26 0.68560 0.22528 5.95298 -0.31648 25 0.97407 0.06753 -1.79775 0.03286 0.85222

10 Magnesium 26 0.66871 0.30175 5.87296 -0.40783 25 0.98129 0.07473 -4.89976 0.08147 1.18107

11 Chloride 26 0.78301 0.30361 6.53177 -0.54864 25 0.96435 0.12810 -3.46286 -0.09789 1.09869

12 Sulfate 26 0.70815 0.34748 8.30186 -0.51490 25 0.98832 0.07242 -4.15904 0.05022 1.36695

13 Carbonate 26 0.65480 0.20412 6.35715 -0.26744 25 0.91030 0.10854 -0.00349 0.01996 0.69872

14 Sodium +K 26 0.76147 0.31080 7.37390 -0.52826 25 0.97667 0.10126 -3.29603 -0.04645 1.17237

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 25 0.89780 0.26014 2.75651 0.59377 24 0.99555 0.05332 -6.47475 0.98404 1.03146

16 Calcium 25 0.75567 0.21590 5.85102 -0.29239 24 0.98478 0.05610 -1.62750 0.02256 0.83686

17 Magnesium 25 0.71648 0.30171 5.70801 -0.36935 24 0.98765 0.06535 -5.15770 0.09293 1.21110

18 Chloride 25 0.83811 0.28794 6.30936 -0.50454 24 0.97339 0.12062 -3.23724 -0.10097 1.06672

19 Sulfate 25 0.83100 0.31058 8.37836 -0.53038 24 0.98127 0.10705 -2.16827 -0.08541 1.17936

20 Carbonate 25 0.64747 0.22387 6.20948 -0.23364 24 0.91694 0.11306 -0.96871 0.07109 0.80077

21 Sodium +K 25 0.83938 0.28574 7.25125 -0.50303 24 0.98507 0.09014 -2.54857 -0.08955 1.09583

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 21 0.89869 0.25314 2.56462 0.62536 20 0.99859 0.02808 -6.88066 0.99800 1.07928

23 Calcium 21 0.68108 0.21026 5.64607 -0.25486 20 0.95976 0.07750 -1.60853 0.02839 0.83205

24 Magnesium 21 0.64776 0.29331 5.48490 -0.32991 20 0.98729 0.05738 -5.51534 0.10877 1.25208

25 Chloride 21 0.80695 0.28141 6.14545 -0.47723 20 0.97540 0.10229 -3.73580 -0.08814 1.12989

26 Sulfate 21 0.79617 0.30770 8.22065 -0.50441 20 0.97766 0.10423 -2.56581 -0.08210 1.23592

27 Carbonate 21 0.55988 0.23372 6.13123 -0.21865 20 0.90471 0.11308 -1.71200 0.09189 0.89508

28 Sodium +K 21 0.80726 0.27541 7.01161 -0.46751 20 0.98954 0.06529 -3.07667 -0.06907 1.15232
92 

5. STATION 09306500 (WHITE) White River near Watson, UT 

STATION 09306500 White River near Watson, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 23 26.1 0.0

2 2009 23 26.1 0.0

3 2010 22 0.0 0.0

4 2011 20 0.0 0.0

5 2012 20 0.0 0.0

STATION 09306500 White River near Watson, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 23 0.92129 0.16870 1.77749 0.72504 22 0.96361 0.11985 -5.8983 0.99955 0.92996

2 Calcium 17 0.70785 0.09553 5.46765 -0.21484 17 0.81333 0.07904 1.7934 -0.08778 0.45042

3 Magnesium 17 0.71084 0.15321 5.24942 -0.34707 17 0.88188 0.10136 -2.2933 -0.08625 0.92466

4 Chloride 17 0.74437 0.25928 6.22128 -0.63926 17 0.91810 0.15191 -7.4608 -0.16613 1.67729

5 Sulfate 17 0.67842 0.25128 8.17862 -0.52733 17 0.88337 0.15664 -4.6620 -0.08331 1.57413

6 Carbonate 17 0.67986 0.08959 5.82456 -0.18863 17 0.78194 0.07653 2.5863 -0.07665 0.39698

7 Sodium +K 17 0.66243 0.28289 7.13379 -0.57256 17 0.91033 0.15092 -8.3840 -0.03596 1.90232

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 23 0.92129 0.16870 1.77749 0.72504 22 0.96361 0.11985 -5.8983 0.99955 0.92996

9 Calcium 17 0.70785 0.09553 5.46765 -0.21484 17 0.81333 0.07904 1.7934 -0.08778 0.45042

10 Magnesium 17 0.71084 0.15321 5.24942 -0.34707 17 0.88188 0.10136 -2.2933 -0.08625 0.92466

11 Chloride 17 0.74437 0.25928 6.22128 -0.63926 17 0.91810 0.15191 -7.4608 -0.16613 1.67729

12 Sulfate 17 0.67842 0.25128 8.17862 -0.52733 17 0.88337 0.15664 -4.6620 -0.08331 1.57413

13 Carbonate 17 0.67986 0.08959 5.82456 -0.18863 17 0.78194 0.07653 2.5863 -0.07665 0.39698

14 Sodium +K 17 0.66243 0.28289 7.13379 -0.57256 17 0.91033 0.15092 -8.3840 -0.03596 1.90232
93 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 22 0.90853 0.17687 1.89009 0.70812 22 0.97998 0.08489 -6.8822 0.99322 1.08852

16 Calcium 22 0.75162 0.09964 5.52915 -0.22019 22 0.87494 0.07254 1.5892 -0.09214 0.48889

17 Magnesium 22 0.62562 0.17844 4.94539 -0.29304 22 0.88611 0.10098 -3.4074 -0.02157 1.03646

18 Chloride 22 0.71169 0.28126 5.78176 -0.56137 22 0.93214 0.14000 -8.0196 -0.11282 1.71255

19 Sulfate 22 0.63989 0.27838 7.89352 -0.47141 22 0.91410 0.13949 -5.7385 -0.02837 1.69154

20 Carbonate 22 0.51863 0.10543 5.52826 -0.13902 22 0.73420 0.08038 1.5688 -0.01034 0.49131

21 Sodium +K 22 0.51917 0.33221 6.35404 -0.43853 22 0.90495 0.15155 -10.3449 0.10419 2.07210

 2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 20 0.92153 0.15837 1.69493 0.73806 20 0.99366 0.04631 -7.6621 1.00940 1.19520

23 Calcium 20 0.74345 0.09140 5.47378 -0.21160 20 0.90152 0.05827 1.0526 -0.08339 0.56473

24 Magnesium 20 0.56765 0.16638 4.72289 -0.25927 20 0.92721 0.07025 -4.6274 0.01188 1.19434

25 Chloride 20 0.66319 0.26817 5.46402 -0.51176 20 0.94555 0.11096 -9.6674 -0.07297 1.93278

26 Sulfate 20 0.61340 0.25003 7.61544 -0.42830 20 0.96459 0.07786 -7.0698 -0.00245 1.87579

27 Carbonate 20 0.46297 0.10077 5.45227 -0.12724 20 0.71271 0.07584 1.2174 -0.00444 0.54093

28 Sodium +K 20 0.45385 0.29624 5.89715 -0.36725 20 0.90117 0.12967 -10.6245 0.11185 2.11035

6. STATION 09315000 (GRUT) Green River at Green River, UT 

STATION 09315000 Green River at Green River, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 18 0.0 0.0

2 2009 18 0.0 0.0

3 2010 23 0.0 0.0

4 2011 20 0.0 0.0

5 2012 20 0.0 0.0

STATION 09315000 Green River at Green River, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
94 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 18 0.77624 0.12945 4.6446 0.43999 18 0.98089 0.03907 -6.31529 0.97648 1.01957

2 Calcium 18 0.77965 0.12226 7.3778 -0.41970 18 0.94166 0.06497 -1.90334 0.03461 0.86340

3 Magnesium 18 0.78970 0.17031 7.9845 -0.60231 18 0.97788 0.05705 -6.27861 0.09587 1.32686

4 Chloride 18 0.88060 0.14441 8.7202 -0.71571 18 0.98539 0.05217 -3.25674 -0.12944 1.11419

5 Sulfate 18 0.84696 0.17291 11.0617 -0.74238 18 0.98836 0.04924 -3.65358 -0.02207 1.36892

6 Carbonate 18 0.66948 0.13569 7.4268 -0.35243 18 0.68934 0.13586 4.48193 -0.20828 0.27395

7 Sodium +K 18 0.87664 0.14108 9.5941 -0.68638 18 0.98897 0.04357 -2.32483 -0.10295 1.10878

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 18 0.77624 0.12945 4.6446 0.43999 18 0.98089 0.03907 -6.31529 0.97648 1.01957

9 Calcium 18 0.77965 0.12226 7.3778 -0.41970 18 0.94166 0.06497 -1.90334 0.03461 0.86340

10 Magnesium 18 0.78970 0.17031 7.9845 -0.60231 18 0.97788 0.05705 -6.27861 0.09587 1.32686

11 Chloride 18 0.88060 0.14441 8.7202 -0.71571 18 0.98539 0.05217 -3.25674 -0.12944 1.11419

12 Sulfate 18 0.84696 0.17291 11.0617 -0.74238 18 0.98836 0.04924 -3.65358 -0.02207 1.36892

13 Carbonate 18 0.66948 0.13569 7.4268 -0.35243 18 0.68934 0.13586 4.48193 -0.20828 0.27395

14 Sodium +K 18 0.87664 0.14108 9.5941 -0.68638 18 0.98897 0.04357 -2.32483 -0.10295 1.10878

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 23 0.93532 0.17145 2.7016 0.68708 23 0.99789 0.03171 -6.64977 0.99673 1.04559

16 Calcium 23 0.68483 0.15357 5.9764 -0.23856 23 0.95714 0.05803 -1.93950 0.02356 0.88509

17 Magnesium 23 0.58698 0.22990 5.5108 -0.28883 23 0.97647 0.05623 -6.86990 0.12113 1.38431

18 Chloride 23 0.84304 0.18661 6.7044 -0.45575 23 0.98249 0.06387 -3.04947 -0.13278 1.09060

19 Sulfate 23 0.75415 0.22615 8.5105 -0.41739 23 0.99422 0.03552 -3.88213 -0.00704 1.38564

20 Carbonate 23 0.60221 0.14776 6.1625 -0.19159 23 0.75312 0.11928 1.11535 -0.02447 0.56434

21 Sodium +K 23 0.80779 0.19005 7.4061 -0.41059 23 0.98646 0.05170 -2.75525 -0.07412 1.13616

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 20 0.93877 0.17100 2.5178 0.70918 20 0.99842 0.02827 -6.83286 1.00538 1.06155

23 Calcium 20 0.66526 0.14728 5.8290 -0.21990 20 0.95238 0.05716 -1.72795 0.01947 0.85792

24 Magnesium 20 0.54366 0.22537 5.2876 -0.26052 20 0.96938 0.06007 -6.77183 0.12147 1.36907

25 Chloride 20 0.83447 0.18579 6.6096 -0.44181 20 0.98018 0.06615 -3.04763 -0.13591 1.09635

26 Sulfate 20 0.72267 0.22625 8.2614 -0.38681 20 0.99055 0.04297 -4.05760 0.00341 1.39854

27 Carbonate 20 0.54456 0.15690 6.0767 -0.18171 20 0.72509 0.12544 0.60383 -0.00835 0.62132

28 Sodium +K 20 0.79647 0.18055 7.1207 -0.37828 20 0.98940 0.04239 -2.61827 -0.06979 1.10563
95 

7. STATION 09328500, San Rafael River near Green River, UT 

 

STATION 09328500 San Rafael River near Green River, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 21 4.8 0.0

2 2009 21 4.8 0.0

3 2010 24 4.2 0.0

4 2011 21 4.8 0.0

5 2012 21 4.8 0.0

STATION 09328500 San Rafael River near Green River, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 21 0.78861 0.27532 3.17694 0.57218 21 0.99483 0.04424 -6.82318 0.95724 1.10180

2 Calcium 20 0.75370 0.22321 6.69419 -0.42440 20 0.87800 0.16165 0.80749 -0.18831 0.64353

3 Magnesium 20 0.63252 0.30149 6.25602 -0.42991 20 0.91800 0.14655 -3.60870 -0.03427 1.07841

4 Chloride 20 0.76040 0.29730 6.04072 -0.57565 20 0.97835 0.09195 -4.48564 -0.15347 1.15074

5 Sulfate 20 0.67266 0.33497 8.89906 -0.52191 20 0.99206 0.05367 -3.38457 -0.02925 1.34285

6 Carbonate 20 0.08412 0.20847 5.24132 -0.06867 20 0.08427 0.21450 5.14365 -0.06475 0.01068

7 Sodium +K 20 0.56640 0.34958 7.15689 -0.43426 20 0.94202 0.13154 -4.92184 0.05018 1.32045

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 21 0.78861 0.27532 3.17694 0.57218 21 0.99483 0.04424 -6.82318 0.95724 1.10180

9 Calcium 20 0.75370 0.22321 6.69419 -0.42440 20 0.87800 0.16165 0.80749 -0.18831 0.64353

10 Magnesium 20 0.63252 0.30149 6.25602 -0.42991 20 0.91800 0.14655 -3.60870 -0.03427 1.07841

11 Chloride 20 0.76040 0.29730 6.04072 -0.57565 20 0.97835 0.09195 -4.48564 -0.15347 1.15074

12 Sulfate 20 0.67266 0.33497 8.89906 -0.52191 20 0.99206 0.05367 -3.38457 -0.02925 1.34285

13 Carbonate 20 0.08412 0.20847 5.24132 -0.06867 20 0.08427 0.21450 5.14365 -0.06475 0.01068

14 Sodium +K 20 0.56640 0.34958 7.15689 -0.43426 20 0.94202 0.13154 -4.92184 0.05018 1.32045
96 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 24 0.91322 0.27988 3.11073 0.60559 24 0.99652 0.05735 -7.77380 1.01978 1.19813

16 Calcium 23 0.63441 0.32537 6.33261 -0.28823 23 0.84332 0.21827 -3.57760 0.09738 1.08479

17 Magnesium 23 0.83678 0.26989 6.23758 -0.41094 23 0.94150 0.16556 -2.47312 -0.07200 0.95349

18 Chloride 23 0.86819 0.29047 5.85465 -0.50132 23 0.96023 0.16350 -3.92505 -0.12079 1.07051

19 Sulfate 23 0.77056 0.38078 8.76808 -0.46927 23 0.98423 0.10228 -6.03819 0.10684 1.62072

20 Carbonate 23 0.41809 0.25822 5.57393 -0.14719 23 0.46308 0.25417 8.46704 -0.25976 -0.31669

21 Sodium +K 23 0.85491 0.29744 7.35691 -0.48552 23 0.96539 0.14885 -3.10134 -0.07859 1.14478

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 21 0.89908 0.30280 3.13435 0.60646 21 0.99707 0.05299 -7.85383 1.02349 1.20737

23 Calcium 20 0.59906 0.34323 6.35369 -0.28647 20 0.83862 0.22407 -3.60498 0.10342 1.08568

24 Magnesium 20 0.80446 0.30530 6.32089 -0.42281 20 0.93289 0.18404 -2.96638 -0.05921 1.01248

25 Chloride 20 0.86183 0.30031 5.98010 -0.51212 20 0.96214 0.16176 -3.62452 -0.13610 1.04708

26 Sulfate 20 0.73878 0.40950 8.80841 -0.47023 20 0.98495 0.10113 -6.11349 0.11397 1.62676

27 Carbonate 20 0.42062 0.27274 5.63125 -0.15867 20 0.44871 0.27376 7.88536 -0.24692 -0.24574

28 Sodium +K 20 0.83420 0.32124 7.41855 -0.49200 20 0.96517 0.15151 -3.29837 -0.07243 1.16834

8. STATION 09071750 (GLEN) Colorado River above Glenwood Springs CO 

 

STATION 09071750 Colorado River above Glenwood Springs, CO UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 20 0.0 0.0

2 2009 20 0.0 0.0

3 2010 18 0.0 0.0

4 2011 16 0.0 0.0

5 2012 16 0.0 0.0

STATION 09071750 Colorado River above Glenwood Springs, CO UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
97 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 20 0.96948 0.07697 3.6189 0.49123 20 0.99765 0.021958 -6.78092 1.01427 1.02902

2 Calcium 20 0.95210 0.06231 6.2100 -0.31456 20 0.98152 0.039823 -0.65685 0.03079 0.67944

3 Magnesium 20 0.86611 0.11718 4.8200 -0.33748 20 0.93875 0.081557 -7.31722 0.27293 1.20093

4 Chloride 20 0.98456 0.10836 11.4559 -0.97967 20 0.98970 0.091052 2.66069 -0.53734 0.87025

5 Sulfate 20 0.93933 0.10805 7.8025 -0.48140 20 0.98293 0.058979 -5.07689 0.16634 1.27436

6 Carbonate 20 0.87360 0.07511 5.7140 -0.22358 20 0.94686 0.050113 -2.32664 0.18080 0.79559

7 Sodium +K 20 0.98370 0.09346 9.9954 -0.82207 20 0.99088 0.071936 1.27268 -0.38338 0.86308

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 20 0.96948 0.07697 3.6189 0.49123 20 0.99765 0.021958 -6.78092 1.01427 1.02902

9 Calcium 20 0.95210 0.06231 6.2100 -0.31456 20 0.98152 0.039823 -0.65685 0.03079 0.67944

10 Magnesium 20 0.86611 0.11718 4.8200 -0.33748 20 0.93875 0.081557 -7.31722 0.27293 1.20093

11 Chloride 20 0.98456 0.10836 11.4559 -0.97967 20 0.98970 0.091052 2.66069 -0.53734 0.87025

12 Sulfate 20 0.93933 0.10805 7.8025 -0.48140 20 0.98293 0.058979 -5.07689 0.16634 1.27436

13 Carbonate 20 0.87360 0.07511 5.7140 -0.22358 20 0.94686 0.050113 -2.32664 0.18080 0.79559

14 Sodium +K 20 0.98370 0.09346 9.9954 -0.82207 20 0.99088 0.071936 1.27268 -0.38338 0.86308

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 18 0.96932 0.07460 3.7740 0.47372 18 0.99437 0.033020 -7.48367 1.05557 1.09275

16 Calcium 18 0.95600 0.06320 6.3518 -0.33279 18 0.97737 0.046813 -1.00421 0.04740 0.71402

17 Magnesium 18 0.89572 0.11153 5.0625 -0.36923 18 0.93641 0.089946 -6.57433 0.23221 1.12954

18 Chloride 18 0.97840 0.12513 11.2994 -0.95141 18 0.98857 0.094035 -3.03701 -0.21043 1.39158

19 Sulfate 18 0.96574 0.08377 7.9675 -0.50237 18 0.98688 0.053531 -3.02372 0.06571 1.06688

20 Carbonate 18 0.89084 0.07718 5.9166 -0.24906 18 0.95413 0.051669 -3.89939 0.25828 0.95280

21 Sodium +K 18 0.97673 0.11040 9.9317 -0.80798 18 0.98848 0.080244 -3.16796 -0.13092 1.27154

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 16 0.93389 0.10178 3.7644 0.47439 16 0.99383 0.032270 -8.22199 1.09714 1.15992

23 Calcium 16 0.88477 0.09931 6.4019 -0.34127 16 0.96622 0.055804 -3.92474 0.19525 0.99930

24 Magnesium 16 0.85575 0.12662 5.1427 -0.38244 16 0.94448 0.081519 -7.13908 0.25566 1.18851

25 Chloride 16 0.97258 0.12393 11.0598 -0.91530 16 0.98550 0.093515 0.53640 -0.36856 1.01835

26 Sulfate 16 0.89250 0.13715 7.8493 -0.49008 16 0.97366 0.070452 -6.88984 0.27569 1.42630

27 Carbonate 16 0.86366 0.08542 6.0483 -0.26662 16 0.95335 0.051856 -2.52073 0.17858 0.82922

28 Sodium +K 16 0.96491 0.11832 9.6520 -0.76945 16 0.98872 0.069608 -2.40322 -0.14312 1.16658
98 

9. STATION 09095500 (CAMEO) Colorado River near Cameo, CO 

STATION 09095500 Colorado River near Cameo, CO UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 14 0.0 0.0

2 2009 14 0.0 0.0

3 2010 14 0.0 0.0

4 2011 12 0.0 0.0

5 2012 12 0.0 0.0

STATION 09095500 Colorado River near Cameo, CO UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 14 0.96681 0.06639 5.0627 0.39782 14 0.99514 0.026530 -6.66857 1.00164 1.02668

2 Calcium 14 0.97769 0.04740 6.8771 -0.34835 14 0.98577 0.039535 1.42120 -0.06753 0.47748

3 Magnesium 14 0.93581 0.09368 5.8244 -0.39708 14 0.95831 0.078852 -4.78275 0.14888 0.92830

4 Chloride 14 0.98934 0.09497 12.8853 -1.01580 14 0.99493 0.068420 -0.26474 -0.33896 1.15084

5 Sulfate 14 0.98081 0.08037 9.6852 -0.63778 14 0.99330 0.049593 -2.71575 0.00051 1.08529

6 Carbonate 14 0.85885 0.08364 6.1535 -0.22903 14 0.88045 0.080393 -0.10378 0.09304 0.54761

7 Sodium +K 14 0.99022 0.07871 11.5208 -0.87921 14 0.99647 0.049357 -0.51833 -0.25955 1.05362

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 14 0.96681 0.06639 5.0627 0.39782 14 0.99514 0.026530 -6.66857 1.00164 1.02668

9 Calcium 14 0.97769 0.04740 6.8771 -0.34835 14 0.98577 0.039535 1.42120 -0.06753 0.47748

10 Magnesium 14 0.93581 0.09368 5.8244 -0.39708 14 0.95831 0.078852 -4.78275 0.14888 0.92830

11 Chloride 14 0.98934 0.09497 12.8853 -1.01580 14 0.99493 0.068420 -0.26474 -0.33896 1.15084

12 Sulfate 14 0.98081 0.08037 9.6852 -0.63778 14 0.99330 0.049593 -2.71575 0.00051 1.08529

13 Carbonate 14 0.85885 0.08364 6.1535 -0.22903 14 0.88045 0.080393 -0.10378 0.09304 0.54761

14 Sodium +K 14 0.99022 0.07871 11.5208 -0.87921 14 0.99647 0.049357 -0.51833 -0.25955 1.05362
99 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 14 0.98221 0.05192 5.1847 0.38460 14 0.99557 0.027046 -5.04707 0.91589 0.88735

16 Calcium 14 0.98273 0.05113 7.1496 -0.38457 14 0.98343 0.052311 4.80608 -0.26288 0.20324

17 Magnesium 14 0.98555 0.05459 6.2429 -0.44946 14 0.98745 0.053138 1.74400 -0.21586 0.39016

18 Chloride 14 0.98897 0.10394 12.6573 -0.98124 14 0.99531 0.070764 -5.26442 -0.05065 1.55426

19 Sulfate 14 0.98871 0.06963 9.7949 -0.64978 14 0.99477 0.049529 -1.79934 -0.04774 1.00551

20 Carbonate 14 0.97440 0.04615 6.5921 -0.28388 14 0.97579 0.046876 4.14842 -0.15699 0.21193

21 Sodium +K 14 0.99142 0.08230 11.5627 -0.88208 14 0.99540 0.062938 -1.18297 -0.22025 1.10537

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 12 0.95896 0.07619 5.2210 0.37765 12 0.99649 0.023499 -5.35006 0.93193 0.91285

23 Calcium 12 0.97729 0.05942 7.2461 -0.39973 12 0.98257 0.054875 3.08852 -0.18173 0.35902

24 Magnesium 12 0.98216 0.06129 6.3709 -0.46632 12 0.98636 0.056500 2.05788 -0.24017 0.37244

25 Chloride 12 0.98550 0.11605 12.6518 -0.98114 12 0.99547 0.068353 -1.31350 -0.24889 1.20596

26 Sulfate 12 0.97663 0.09909 9.8130 -0.65685 12 0.99530 0.046853 -3.03774 0.01696 1.10971

27 Carbonate 12 0.98653 0.03328 6.6515 -0.29205 12 0.98855 0.032336 4.78036 -0.19394 0.16158

28 Sodium +K 12 0.98966 0.08800 11.5458 -0.88268 12 0.99701 0.049890 0.78077 -0.31823 0.92960

10. STATION 09152500 (GUNN) Gunnison River near Grand Junction, CO 

STATION 09152500 Gunnison River near Grand Junction, Co UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 15 0.0 0.0

2 2009 15 0.0 0.0

3 2010 17 0.0 0.0

4 2011 17 0.0 0.0

5 2012 17 0.0 0.0

STATION 09152500 Gunnison River near Grand Junction, Co UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
100 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 15 0.71131 0.19451 4.6604 0.42188 15 0.99489 0.02693 -6.95283 0.98442 1.11542

2 Calcium 15 0.70369 0.22099 7.9531 -0.47057 15 0.97042 0.07268 -4.67757 0.14125 1.21314

3 Magnesium 15 0.85937 0.17521 7.7851 -0.59848 15 0.97929 0.06999 -1.96157 -0.12636 0.93614

4 Chloride 15 0.90059 0.15537 6.8137 -0.64613 15 0.93143 0.13430 1.60021 -0.39359 0.50074

5 Sulfate 15 0.83706 0.24428 11.2737 -0.76502 15 0.99232 0.05520 -3.09087 -0.06921 1.37967

6 Carbonate 15 0.73688 0.13502 6.7231 -0.31222 15 0.90411 0.08484 0.23857 0.00189 0.62281

7 Sodium +K 15 0.86632 0.18817 8.7967 -0.66188 15 0.97075 0.09161 -1.22197 -0.17658 0.96226

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 15 0.71131 0.19451 4.6604 0.42188 15 0.99489 0.02693 -6.95283 0.98442 1.11542

9 Calcium 15 0.70369 0.22099 7.9531 -0.47057 15 0.97042 0.07268 -4.67757 0.14125 1.21314

10 Magnesium 15 0.85937 0.17521 7.7851 -0.59848 15 0.97929 0.06999 -1.96157 -0.12636 0.93614

11 Chloride 15 0.90059 0.15537 6.8137 -0.64613 15 0.93143 0.13430 1.60021 -0.39359 0.50074

12 Sulfate 15 0.83706 0.24428 11.2737 -0.76502 15 0.99232 0.05520 -3.09087 -0.06921 1.37967

13 Carbonate 15 0.73688 0.13502 6.7231 -0.31222 15 0.90411 0.08484 0.23857 0.00189 0.62281

14 Sodium +K 15 0.86632 0.18817 8.7967 -0.66188 15 0.97075 0.09161 -1.22197 -0.17658 0.96226

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 17 0.68657 0.21568 3.5710 0.57250 17 0.99400 0.03090 -6.78438 0.98444 1.09021

16 Calcium 17 0.36011 0.24092 6.9036 -0.32415 17 0.93744 0.07797 -4.19060 0.11718 1.16799

17 Magnesium 17 0.66000 0.19432 6.9777 -0.48558 17 0.96624 0.06338 -1.96297 -0.12992 0.94128

18 Chloride 17 0.83982 0.14485 6.4322 -0.59485 17 0.90321 0.11655 2.01459 -0.41912 0.46508

19 Sulfate 17 0.53117 0.26815 9.4293 -0.51192 17 0.98982 0.04089 -3.42888 -0.00042 1.35371

20 Carbonate 17 0.63628 0.13284 6.7603 -0.31512 17 0.85948 0.08547 1.71527 -0.11443 0.53114

21 Sodium +K 17 0.66577 0.21066 7.8561 -0.53324 17 0.93782 0.09405 -1.35774 -0.16671 0.97003

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 17 0.71795 0.19963 3.2612 0.60983 17 0.99109 0.03672 -6.56751 0.97242 1.07307

23 Calcium 17 0.30925 0.22158 6.5745 -0.28387 17 0.91767 0.07918 -3.82975 0.09994 1.13590

24 Magnesium 17 0.65543 0.17774 6.8422 -0.46936 17 0.95091 0.06944 -1.39259 -0.16558 0.89904

25 Chloride 17 0.81922 0.13517 6.0765 -0.55095 17 0.90978 0.09884 1.29016 -0.37438 0.52256

26 Sulfate 17 0.47299 0.25539 9.0238 -0.46326 17 0.98669 0.04201 -3.59150 0.00212 1.37730

27 Carbonate 17 0.69548 0.10897 6.7543 -0.31531 17 0.83923 0.08195 3.00864 -0.17713 0.40894

28 Sodium +K 17 0.62380 0.19289 7.3872 -0.47559 17 0.93653 0.08201 -1.41187 -0.15099 0.96065
101 

11. STATION 09180000 (DOLOR) Dolores River near Cisco, UT 

STATION 09180000 Dolores River near Cisco, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 23 4.3 0.0

2 2009 23 4.3 0.0

3 2010 25 4.0 0.0

4 2011 21 4.8 0.0

5 2012 21 4.8 0.0

STATION 09180000 Dolores River near Cisco, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 23 0.77776 0.29150 3.51376 0.47390 23 0.99355 0.05088 -5.99828 0.96697 0.96203

2 Calcium 22 0.76891 0.22137 6.32233 -0.34389 22 0.84545 0.18573 1.94579 -0.11917 0.44584

3 Magnesium 22 0.87761 0.21304 5.87470 -0.48585 22 0.95870 0.12698 -0.08228 -0.17998 0.60684

4 Chloride 22 0.74619 0.57642 9.56336 -0.84171 22 0.90555 0.36077 -6.12695 -0.03606 1.59838

5 Sulfate 22 0.79684 0.33428 8.34168 -0.56381 22 0.85453 0.29021 2.22256 -0.24961 0.62336

6 Carbonate 22 0.64243 0.14522 5.30976 -0.16577 22 0.71032 0.13410 3.13598 -0.05415 0.22144

7 Sodium +K 22 0.76507 0.46722 8.63561 -0.71806 22 0.94550 0.23087 -5.43046 0.00419 1.43292

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 23 0.77776 0.29150 3.51376 0.47390 23 0.99355 0.05088 -5.99828 0.96697 0.96203

9 Calcium 22 0.76891 0.22137 6.32233 -0.34389 22 0.84545 0.18573 1.94579 -0.11917 0.44584

10 Magnesium 22 0.87761 0.21304 5.87470 -0.48585 22 0.95870 0.12698 -0.08228 -0.17998 0.60684

11 Chloride 22 0.74619 0.57642 9.56336 -0.84171 22 0.90555 0.36077 -6.12695 -0.03606 1.59838

12 Sulfate 22 0.79684 0.33428 8.34168 -0.56381 22 0.85453 0.29021 2.22256 -0.24961 0.62336

13 Carbonate 22 0.64243 0.14522 5.30976 -0.16577 22 0.71032 0.13410 3.13598 -0.05415 0.22144

14 Sodium +K 22 0.76507 0.46722 8.63561 -0.71806 22 0.94550 0.23087 -5.43046 0.00419 1.43292
102 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 25 0.77801 0.26403 3.45492 0.48071 25 0.99165 0.05237 -5.96292 0.96708 0.95830

16 Calcium 24 0.72701 0.22134 6.31101 -0.34462 24 0.80167 0.19310 1.84651 -0.11622 0.45747

17 Magnesium 24 0.87797 0.19162 5.88152 -0.49039 24 0.94524 0.13139 0.39373 -0.20964 0.56233

18 Chloride 24 0.71563 0.53250 9.35103 -0.80595 24 0.88810 0.34190 -6.64495 0.01240 1.63910

19 Sulfate 24 0.75760 0.33540 8.35587 -0.56571 24 0.80975 0.30413 2.35535 -0.25873 0.61487

20 Carbonate 24 0.74778 0.11486 5.43042 -0.18869 24 0.76449 0.11360 4.28995 -0.13035 0.11686

21 Sodium +K 24 0.74029 0.42685 8.43517 -0.68756 24 0.93466 0.21913 -5.80837 0.04113 1.45953

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 21 0.71965 0.28160 3.68608 0.44419 21 0.99092 0.05208 -5.92463 0.96127 0.95840

23 Calcium 20 0.70518 0.23996 6.39675 -0.35783 20 0.80317 0.20175 1.36539 -0.09079 0.50662

24 Magnesium 20 0.87606 0.19566 5.95783 -0.50157 20 0.95326 0.12364 0.34167 -0.20350 0.56551

25 Chloride 20 0.71309 0.58960 9.88475 -0.89622 20 0.89469 0.36756 -7.17496 0.00920 1.71779

26 Sulfate 20 0.75273 0.34965 8.50090 -0.58820 20 0.82432 0.30326 1.65853 -0.22505 0.68898

27 Carbonate 20 0.87800 0.09183 5.74152 -0.23753 20 0.88781 0.09061 4.79442 -0.18726 0.09537

28 Sodium +K 20 0.73730 0.45819 8.74908 -0.74011 20 0.93592 0.23285 -5.74062 0.02892 1.45901

12. STATION 09180500 (CISCO) Colorado River near Cisco, UT 

STATION 09180500 Colorado River near Cisco, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 22 0.0 0.0

2 2009 22 0.0 0.0

3 2010 24 0.0 0.0

4 2011 19 0.0 0.0

5 2012 19 0.0 0.0

STATION 09180500 Colorado River near Cisco, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
103 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 22 0.74565 0.11570 6.1889 0.32592 22 0.97842 0.03457 -7.1547 1.01326 1.09399

2 Calcium 22 0.79206 0.15350 8.6044 -0.49286 22 0.92220 0.09633 -6.0350 0.26123 1.20023

3 Magnesium 22 0.93540 0.10289 8.6716 -0.64415 22 0.98958 0.04240 -2.6885 -0.05898 0.93137

4 Chloride 22 0.91069 0.18505 12.6451 -0.97218 22 0.93322 0.16418 1.4411 -0.39506 0.91857

5 Sulfate 22 0.87621 0.17444 11.8645 -0.76353 22 0.95398 0.10912 -4.8039 0.09508 1.36658

6 Carbonate 22 0.71761 0.12486 7.2194 -0.32747 22 0.84136 0.09602 -2.7448 0.18580 0.81693

7 Sodium +K 22 0.93937 0.13173 11.6529 -0.85303 22 0.96202 0.10696 1.9454 -0.35298 0.79588

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 22 0.74565 0.11570 6.1889 0.32592 22 0.97842 0.03457 -7.1547 1.01326 1.09399

9 Calcium 22 0.79206 0.15350 8.6044 -0.49286 22 0.92220 0.09633 -6.0350 0.26123 1.20023

10 Magnesium 22 0.93540 0.10289 8.6716 -0.64415 22 0.98958 0.04240 -2.6885 -0.05898 0.93137

11 Chloride 22 0.91069 0.18505 12.6451 -0.97218 22 0.93322 0.16418 1.4411 -0.39506 0.91857

12 Sulfate 22 0.87621 0.17444 11.8645 -0.76353 22 0.95398 0.10912 -4.8039 0.09508 1.36658

13 Carbonate 22 0.71761 0.12486 7.2194 -0.32747 22 0.84136 0.09602 -2.7448 0.18580 0.81693

14 Sodium +K 22 0.93937 0.13173 11.6529 -0.85303 22 0.96202 0.10696 1.9454 -0.35298 0.79588

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 24 0.85581 0.09587 6.0441 0.34547 24 0.99060 0.02506 -6.8076 1.00227 1.05699

16 Calcium 24 0.82686 0.15172 8.5967 -0.49042 24 0.93515 0.09504 -8.0400 0.35983 1.36828

17 Magnesium 24 0.93835 0.10538 8.3772 -0.60809 24 0.98807 0.04745 -4.7440 0.06249 1.07916

18 Chloride 24 0.95793 0.13797 12.6973 -0.97384 24 0.95858 0.14012 10.3137 -0.85202 0.19604

19 Sulfate 24 0.88268 0.18446 11.7541 -0.74837 24 0.96584 0.10187 -9.7789 0.35211 1.77098

20 Carbonate 24 0.93076 0.05877 7.1668 -0.31873 24 0.95066 0.05078 2.7992 -0.09551 0.35921

21 Sodium +K 24 0.97392 0.09317 11.5832 -0.84209 24 0.97688 0.08977 7.2273 -0.61947 0.35824

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 19 0.82244 0.11553 5.7751 0.37434 19 0.99391 0.02205 -7.1290 1.02306 1.07849

23 Calcium 19 0.77203 0.16876 8.3791 -0.46756 19 0.92942 0.09679 -7.5585 0.33366 1.33201

24 Magnesium 19 0.90456 0.12613 8.1604 -0.58459 19 0.98572 0.05029 -5.0595 0.08000 1.10488

25 Chloride 19 0.95516 0.13646 12.4602 -0.94819 19 0.95745 0.13701 8.9518 -0.77182 0.29322

26 Sulfate 19 0.84457 0.20523 11.4873 -0.72024 19 0.97293 0.08828 -9.7111 0.34545 1.77169

27 Carbonate 19 0.93396 0.05520 7.1100 -0.31252 19 0.96575 0.04098 2.7569 -0.09369 0.36381

28 Sodium +K 19 0.97495 0.08451 11.1395 -0.79371 19 0.98405 0.06950 5.3489 -0.50261 0.48396
104 

13. STATION 09355500 (ARCH) San Juan River near Archuleta, NM 

Note: no QW samples were collected for this site in WY 2008. QW samples for this site 

were taken in WY 2006 and 2007, and starting again in WY 2009. 

Because of the 3 year sliding method used by SLOAD, the missing 2008 QW data caused 

the SLOAD salt load results for WY 2008 to be unusable (very low value = 12). 

The manual regression spreadsheet (arch12regression.xlsx) which was used for update 

2010 was therefore used again for the 2012 update to manually compute salt loads for WY 

2008-2011. 

If the sampling program which started in WY 2009 continues, sufficient data should exist 

to compute accurate salt loads using SLOAD for update 2014. 

The SLOAD regression statistics are included here for reference, despite the fact that they 

were not used for the published loads. 

STATION 09355500 San Juan River near Archuleta, NM UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2009 10 10.0 0.0

2 2010 10 10.0 0.0

3 2011 8 25.0 0.0

4 2012 8 25.0 0.0

STATION 09355500 San Juan River near Archuleta, NM UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 10 0.99702 0.043156 -0.93831 1.00324 10 0.99724 0.044399 -2.28154 1.00211 0.24548

2 Calcium 9 0.02222 0.046991 3.28431 0.00859 9 0.22628 0.045151 0.80776 0.00436 0.45564

3 Magnesium 9 0.37162 0.036427 1.45983 0.03398 9 0.37791 0.039148 1.03917 0.03326 0.07739

4 Chloride 9 0.11659 0.062600 0.78469 0.02758 9 0.11755 0.067578 0.54636 0.02718 0.04385

5 Sulfate 9 0.03686 0.030666 3.67486 -0.00728 9 0.14604 0.031190 4.86598 -0.00524 -0.21915

6 Carbonate 9 0.18203 0.025626 3.77686 0.01466 9 0.51223 0.021374 5.65522 0.01787 -0.34558

7 Sodium +K 9 0.20304 0.048548 2.45968 0.02972 9 0.29562 0.049298 4.36867 0.03298 -0.35122
105 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 10 0.99702 0.043156 -0.93831 1.00324 10 0.99724 0.044399 -2.28154 1.00211 0.24548

9 Calcium 9 0.02222 0.046991 3.28431 0.00859 9 0.22628 0.045151 0.80776 0.00436 0.45564

10 Magnesium 9 0.37162 0.036427 1.45983 0.03398 9 0.37791 0.039148 1.03917 0.03326 0.07739

11 Chloride 9 0.11659 0.062600 0.78469 0.02758 9 0.11755 0.067578 0.54636 0.02718 0.04385

12 Sulfate 9 0.03686 0.030666 3.67486 -0.00728 9 0.14604 0.031190 4.86598 -0.00524 -0.21915

13 Carbonate 9 0.18203 0.025626 3.77686 0.01466 9 0.51223 0.021374 5.65522 0.01787 -0.34558

14 Sodium +K 9 0.20304 0.048548 2.45968 0.02972 9 0.29562 0.049298 4.36867 0.03298 -0.35122

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 8 0.99788 0.043054 -0.88697 0.99737 8 0.99922 0.028677 -8.09591 1.00784 1.29622

16 Calcium 6 0.02639 0.038286 3.29914 0.00609 6 0.44146 0.033484 -2.44094 0.00829 1.04098

17 Magnesium 6 0.73867 0.021264 1.45342 0.03454 6 0.73867 0.024553 1.46885 0.03454 -0.00280

18 Chloride 6 0.00221 0.049998 0.99468 0.00227 6 0.25895 0.049754 -4.82881 0.00451 1.05611

19 Sulfate 6 0.01894 0.033119 3.65823 -0.00445 6 0.09343 0.036762 1.56281 -0.00364 0.38001

20 Carbonate 6 0.41650 0.016093 3.79588 0.01314 6 0.41752 0.018566 3.94992 0.01308 -0.02793

21 Sodium +K 6 0.13244 0.063656 2.51233 0.02403 6 0.37126 0.062574 -5.15634 0.02698 1.39074

14. STATION 09379500 (BLUFF) San Juan River near Bluff, UT 

STATION 09379500 San Juan River near Bluff, UT UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 23 0.0 0.0

2 2009 23 0.0 0.0

3 2010 24 0.0 0.0

4 2011 21 0.0 0.0

5 2012 21 0.0 0.0

STATION 09379500 San Juan River near Bluff, UT UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
106 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 23 0.66630 0.29334 2.94656 0.58275 23 0.99486 0.03731 -7.11909 0.99633 1.12060

2 Calcium 23 0.39941 0.27948 6.41598 -0.32041 23 0.88995 0.12259 -2.31828 0.03847 0.97238

3 Magnesium 23 0.58577 0.26623 5.77977 -0.44508 23 0.82093 0.17937 -1.15687 -0.16007 0.77225

4 Chloride 23 0.67747 0.28185 6.48655 -0.57429 23 0.95381 0.10930 -2.53528 -0.20359 1.00440

5 Sulfate 23 0.47090 0.39159 8.75215 -0.51937 23 0.98787 0.06076 -4.63327 0.03062 1.49019

6 Carbonate 23 0.66806 0.15266 6.40134 -0.30448 23 0.73336 0.14021 4.05981 -0.20827 0.26068

7 Sodium +K 23 0.53235 0.37893 7.63742 -0.56839 23 0.89912 0.18034 -3.96730 -0.09157 1.29195

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 23 0.66630 0.29334 2.94656 0.58275 23 0.99486 0.03731 -7.11909 0.99633 1.12060

9 Calcium 23 0.39941 0.27948 6.41598 -0.32041 23 0.88995 0.12259 -2.31828 0.03847 0.97238

10 Magnesium 23 0.58577 0.26623 5.77977 -0.44508 23 0.82093 0.17937 -1.15687 -0.16007 0.77225

11 Chloride 23 0.67747 0.28185 6.48655 -0.57429 23 0.95381 0.10930 -2.53528 -0.20359 1.00440

12 Sulfate 23 0.47090 0.39159 8.75215 -0.51937 23 0.98787 0.06076 -4.63327 0.03062 1.49019

13 Carbonate 23 0.66806 0.15266 6.40134 -0.30448 23 0.73336 0.14021 4.05981 -0.20827 0.26068

14 Sodium +K 23 0.53235 0.37893 7.63742 -0.56839 23 0.89912 0.18034 -3.96730 -0.09157 1.29195

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 24 0.54291 0.29211 2.83134 0.60330 24 0.99388 0.03459 -7.30646 1.01617 1.12948

16 Calcium 24 0.21148 0.27478 6.07738 -0.26968 24 0.87482 0.11206 -2.72847 0.08894 0.98109

17 Magnesium 24 0.51412 0.27336 6.40307 -0.53287 24 0.74918 0.20103 -0.24014 -0.26233 0.74014

18 Chloride 24 0.55402 0.28078 6.65888 -0.59307 24 0.93010 0.11378 -2.35019 -0.22617 1.00373

19 Sulfate 24 0.29977 0.38092 8.47989 -0.47233 24 0.99193 0.04185 -4.75275 0.06658 1.47429

20 Carbonate 24 0.66184 0.13039 6.65961 -0.34569 24 0.79920 0.10284 3.75608 -0.22744 0.32349

21 Sodium +K 24 0.38307 0.38716 7.73753 -0.57815 24 0.86522 0.18522 -4.22139 -0.09112 1.33238

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 21 0.62805 0.25623 1.59887 0.79109 21 0.99388 0.03376 -7.18531 0.99111 1.13855

23 Calcium 21 0.02711 0.25503 4.97261 -0.10116 21 0.78223 0.12397 -2.79415 0.07570 1.00668

24 Magnesium 21 0.27077 0.26691 5.43110 -0.38644 21 0.52978 0.22021 -0.06771 -0.26122 0.71272

25 Chloride 21 0.43004 0.20489 5.57377 -0.42285 21 0.88265 0.09551 -0.73763 -0.27914 0.81804

26 Sulfate 21 0.06617 0.32774 6.73482 -0.20729 21 0.98404 0.04403 -4.49739 0.04847 1.45584

27 Carbonate 21 0.56948 0.12844 6.69966 -0.35099 21 0.77040 0.09637 3.66650 -0.28192 0.39314

28 Sodium +K 21 0.13583 0.33504 6.02228 -0.31560 21 0.72470 0.19429 -3.53816 -0.09790 1.23916
107 

15. STATION 09380000 (LEES) Colorado River at Lees Ferry, AZ 

STATION 09380000 Colorado River at Lees Ferry, AZ UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 12 0.0 0.0

2 2009 12 0.0 0.0

3 2010 12 0.0 0.0

4 2011 11 0.0 0.0

5 2012 11 0.0 0.0

STATION 09380000 Colorado River at Lees Ferry, AZ UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 12 0.97376 0.06660 -0.74986 1.09785 12 0.99882 0.014902 -6.80822 1.01248 1.04104

2 Calcium 12 0.21259 0.07327 3.17293 0.10301 12 0.72648 0.045521 -2.33708 0.02537 0.94681

3 Magnesium 12 0.25935 0.05261 2.19803 0.08423 12 0.61764 0.039846 -1.20820 0.03624 0.58531

4 Chloride 12 0.14825 0.09918 2.67582 0.11196 12 0.76001 0.055496 -5.14861 0.00171 1.34451

5 Sulfate 12 0.23435 0.08274 4.00267 0.12385 12 0.94720 0.022902 -3.42869 0.01914 1.27696

6 Carbonate 12 0.09550 0.03058 4.13038 0.02689 12 0.63056 0.020601 1.94100 -0.00396 0.37621

7 Sodium +K 12 0.16154 0.08559 3.12042 0.10165 12 0.87002 0.035523 -4.20363 -0.00155 1.25852

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 12 0.97376 0.06660 -0.74986 1.09785 12 0.99882 0.014902 -6.80822 1.01248 1.04104

9 Calcium 12 0.21259 0.07327 3.17293 0.10301 12 0.72648 0.045521 -2.33708 0.02537 0.94681

10 Magnesium 12 0.25935 0.05261 2.19803 0.08423 12 0.61764 0.039846 -1.20820 0.03624 0.58531

11 Chloride 12 0.14825 0.09918 2.67582 0.11196 12 0.76001 0.055496 -5.14861 0.00171 1.34451

12 Sulfate 12 0.23435 0.08274 4.00267 0.12385 12 0.94720 0.022902 -3.42869 0.01914 1.27696

13 Carbonate 12 0.09550 0.03058 4.13038 0.02689 12 0.63056 0.020601 1.94100 -0.00396 0.37621

14 Sodium +K 12 0.16154 0.08559 3.12042 0.10165 12 0.87002 0.035523 -4.20363 -0.00155 1.25852
108 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 12 0.96702 0.05031 -0.15673 1.03311 12 0.99659 0.017051 -7.72330 1.02931 1.15681

16 Calcium 12 0.00915 0.05580 3.94689 0.02033 12 0.59099 0.037790 -2.84422 0.01692 1.03826

17 Magnesium 12 0.13111 0.03422 2.50827 0.05040 12 0.68779 0.021624 -1.84223 0.04822 0.66512

18 Chloride 12 0.00693 0.09948 3.42426 0.03151 12 0.68492 0.059066 -9.63019 0.02496 1.99583

19 Sulfate 12 0.05563 0.05288 4.68124 0.04866 12 0.85583 0.021780 -3.04975 0.04479 1.18195

20 Carbonate 12 0.07925 0.03036 4.70516 -0.03378 12 0.58088 0.021594 1.14581 -0.03556 0.54417

21 Sodium +K 12 0.09470 0.07130 3.22922 0.08743 12 0.88319 0.026996 -7.33825 0.08213 1.61560

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 11 0.89251 0.09244 0.28351 0.98462 11 0.99636 0.018050 -6.27778 1.00440 0.97468

23 Calcium 11 0.00351 0.08225 3.94077 0.01804 11 0.70982 0.047077 -1.05963 0.03312 0.74281

24 Magnesium 11 0.00010 0.05781 3.00701 -0.00210 11 0.84058 0.024482 -0.82015 0.00943 0.56852

25 Chloride 11 0.01787 0.17940 4.55211 -0.08945 11 0.96940 0.033586 -8.19942 -0.05101 1.89424

26 Sulfate 11 0.00033 0.11244 5.03520 0.00757 11 0.97462 0.019005 -2.98081 0.03173 1.19078

27 Carbonate 11 0.09970 0.03833 4.82974 -0.04715 11 0.79512 0.019396 2.39688 -0.03982 0.36140

28 Sodium +K 11 0.00006 0.12475 4.00605 0.00345 11 0.93153 0.034624 -4.68841 0.02966 1.29156

16. STATION 09402500 (GRCAN) Colorado River near Grand Canyon, AZ 

 – NO REGRESSION STATS

No QW since late 1980’s. Alternate method from Mueller calculates GRCAN load from Lees Ferry 

load and the flow difference between GRCAN and LEES. See no.15 STATION 09380000 (LEES) 

Colorado River at Lees Ferry, AZ 

COLORADO RIVER NEAR GRAND CANYON-09402500- MONTHLY Q, LOAD, TDS DATA, JAN 2009-

DECEMBER 2011 

Obs YEAR MONTH WMONTH GCQ GCLOAD MTDS 

16 2009 1 Jan 856,004 519,766 447 

17 2009 2 Feb 651,350 444,304 502 

18 2009 3 Mar 706,739 514,361 535 

19 2009 4 Apr 654,548 478,810 538 

20 2009 5 May 637,619 451,811 521 

21 2009 6 Jun 706,119 474,189 494 

22 2009 7 Jul 856,345 556,193 478 
109 

Obs YEAR MONTH WMONTH GCQ GCLOAD MTDS 

23 2009 8 Aug 852,439 554,049 478 

24 2009 9 Sep 641,436 430,431 494 

25 2009 10 Oct 659,002 441,353 493 

26 2009 11 Nov 724,479 464,116 471 

27 2009 12 Dec 944,463 547,910 427 

28 2010 1 Jan 966,158 551,831 420 

29 2010 2 Feb 679,142 447,495 485 

30 2010 3 Mar 670,935 484,356 531 

31 2010 4 Apr 703,227 518,730 543 

32 2010 5 May 647,749 465,964 529 

33 2010 6 Jun 636,192 429,961 497 

34 2010 7 Jul 852,635 547,679 472 

35 2010 8 Aug 917,345 586,185 470 

36 2010 9 Sep 533,721 360,483 497 

37 2010 10 Oct 543,087 376,024 509 

38 2010 11 Nov 840,643 546,872 478 

39 2010 12 Dec 899,046 581,923 476 

40 2011 1 Jan 1,036,542 652,517 463 

41 2011 2 Feb 1,009,377 662,826 483 

42 2011 3 Mar 1,088,747 763,138 516 

43 2011 4 Apr 1,006,243 731,122 534 

44 2011 5 May 1,211,860 835,743 507 

45 2011 6 Jun 1,415,469 940,555 489 

46 2011 7 Jul 1,533,417 1,001,864 481 

47 2011 8 Aug 1,537,255 967,317 463 

48 2011 9 Sep 998,567 627,771 462 

49 2011 10 Oct 1,014,408 618,341 448 

50 2011 11 Nov 1,127,689 662,007 432 

51 2011 12 Dec 1,257,872 676,321 395 
110 

17. STATION 09415000 (VIRGIN) Virgin River at Littlefield, AZ 

STATION 09415000 Virgin River at Littlefield, AZ UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 10 0.0 0.0

2 2009 10 0.0 0.0

3 2010 10 0.0 0.0

4 2011 8 0.0 0.0

5 2012 8 0.0 0.0

STATION 09415000 Virgin River at Littlefield, AZ UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 10 0.99224 0.02762 2.24450 0.89732 10 0.99570 0.02198 -4.1260 0.97891 0.74469

2 Calcium 10 0.75261 0.03421 6.46321 -0.17139 10 0.79162 0.03357 1.7725 -0.11131 0.54833

3 Magnesium 10 0.74465 0.03789 5.35507 -0.18584 10 0.78783 0.03692 -0.0246 -0.11694 0.62886

4 Chloride 10 0.05972 0.05935 5.72697 0.04296 10 0.33011 0.05355 -5.2615 0.18368 1.28451

5 Sulfate 10 0.85208 0.03886 8.07968 -0.26783 10 0.92488 0.02960 -1.3315 -0.14730 1.10013

6 Carbonate 10 0.28471 0.08687 4.33295 0.15740 10 0.32859 0.08997 11.7620 0.06226 -0.86843

7 Sodium +K 10 0.59254 0.04165 5.05647 0.14424 10 0.61571 0.04324 1.6275 0.18816 0.40083

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 10 0.99224 0.02762 2.24450 0.89732 10 0.99570 0.02198 -4.1260 0.97891 0.74469

9 Calcium 10 0.75261 0.03421 6.46321 -0.17139 10 0.79162 0.03357 1.7725 -0.11131 0.54833

10 Magnesium 10 0.74465 0.03789 5.35507 -0.18584 10 0.78783 0.03692 -0.0246 -0.11694 0.62886

11 Chloride 10 0.05972 0.05935 5.72697 0.04296 10 0.33011 0.05355 -5.2615 0.18368 1.28451

12 Sulfate 10 0.85208 0.03886 8.07968 -0.26783 10 0.92488 0.02960 -1.3315 -0.14730 1.10013

13 Carbonate 10 0.28471 0.08687 4.33295 0.15740 10 0.32859 0.08997 11.7620 0.06226 -0.86843

14 Sodium +K 10 0.59254 0.04165 5.05647 0.14424 10 0.61571 0.04324 1.6275 0.18816 0.40083
111 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 10 0.92601 0.08186 3.63992 0.59617 10 0.99510 0.02252 -7.8306 1.04566 1.16677

16 Calcium 10 0.85452 0.07453 7.35762 -0.37185 10 0.94446 0.04923 -1.1399 -0.03886 0.86436

17 Magnesium 10 0.90382 0.05094 5.97392 -0.32149 10 0.95203 0.03846 0.7440 -0.11655 0.53198

18 Chloride 10 0.78159 0.12804 8.27252 -0.49864 10 0.92994 0.07752 -7.0297 0.10101 1.55653

19 Sulfate 10 0.93230 0.06477 9.13761 -0.49483 10 0.98250 0.03520 1.0498 -0.17789 0.82269

20 Carbonate 10 0.00189 0.18174 4.92101 0.01628 10 0.63134 0.11808 -16.0073 0.83639 2.12881

21 Sodium +K 10 0.64896 0.13400 7.47620 -0.37509 10 0.93514 0.06158 -10.0685 0.31243 1.78463

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 8 0.91372 0.08490 3.81812 0.56255 6 0.99982 0.00525 -7.4043 1.01442 1.13348

23 Calcium 8 0.81271 0.08615 7.33125 -0.36538 6 0.93717 0.07005 -1.4813 -0.01794 0.89385

24 Magnesium 8 0.89131 0.05572 5.99481 -0.32484 6 0.95697 0.04887 -0.0502 -0.08230 0.61121

25 Chloride 8 0.86178 0.11502 8.72548 -0.58474 6 0.97618 0.06511 -3.5324 -0.09054 1.23700

26 Sulfate 8 0.93433 0.06823 9.29482 -0.52396 6 0.99512 0.02565 0.2422 -0.15655 0.91306

27 Carbonate 8 0.01516 0.20071 4.73992 0.05071 6 0.71324 0.14640 -18.6706 0.98790 2.36786

28 Sodium +K 8 0.79202 0.11260 7.84869 -0.44735 6 0.98898 0.03578 -6.2847 0.11920 1.42860

18. STATION 09421500 (HOOVER) Colorado River below Hoover Dam, AZNV 

STATION 09421500 Colorado River below Hoover Dam, AZ UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 39 0.0 0.0

2 2009 39 0.0 0.0

3 2010 40 0.0 0.0

4 2011 37 0.0 0.0

5 2012 37 0.0 0.0

STATION 09421500 Colorado River below Hoover Dam, AZ UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
112 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 39 0.99035 0.040140 0.59336 0.98994 39 0.99737 0.021261 -5.35045 0.99073 0.86071

2 Calcium 39 0.01254 0.047268 4.47141 -0.01297 39 0.28619 0.040742 0.15013 -0.01239 0.62575

3 Magnesium 39 0.00232 0.091012 3.38639 -0.01068 39 0.36545 0.073584 -6.14909 -0.00942 1.38081

4 Chloride 39 0.01032 0.050545 4.54602 -0.01257 39 0.52056 0.035665 -1.75662 -0.01173 0.91267

5 Sulfate 39 0.00002 0.052863 5.46705 -0.00053 39 0.77906 0.025191 -2.63590 0.00054 1.17337

6 Carbonate 39 0.00521 0.031364 4.47747 -0.00553 39 0.19840 0.028542 2.07721 -0.00521 0.34758

7 Sodium +K 39 0.05537 0.051780 4.84289 -0.03051 39 0.23582 0.047215 0.91265 -0.02999 0.56913

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 39 0.99035 0.040140 0.59336 0.98994 39 0.99737 0.021261 -5.35045 0.99073 0.86071

9 Calcium 39 0.01254 0.047268 4.47141 -0.01297 39 0.28619 0.040742 0.15013 -0.01239 0.62575

10 Magnesium 39 0.00232 0.091012 3.38639 -0.01068 39 0.36545 0.073584 -6.14909 -0.00942 1.38081

11 Chloride 39 0.01032 0.050545 4.54602 -0.01257 39 0.52056 0.035665 -1.75662 -0.01173 0.91267

12 Sulfate 39 0.00002 0.052863 5.46705 -0.00053 39 0.77906 0.025191 -2.63590 0.00054 1.17337

13 Carbonate 39 0.00521 0.031364 4.47747 -0.00553 39 0.19840 0.028542 2.07721 -0.00521 0.34758

14 Sodium +K 39 0.05537 0.051780 4.84289 -0.03051 39 0.23582 0.047215 0.91265 -0.02999 0.56913

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 40 0.98615 0.045296 0.67247 0.97798 40 0.99222 0.034392 -5.81572 0.98498 0.93513

16 Calcium 40 0.00077 0.060921 4.36394 -0.00433 40 0.29361 0.051910 -2.76848 0.00337 1.02798

17 Magnesium 40 0.00590 0.070169 3.37055 -0.01383 40 0.20286 0.063678 -3.38420 -0.00654 0.97355

18 Chloride 40 0.03002 0.047456 4.59704 -0.02136 40 0.31570 0.040395 -0.97279 -0.01535 0.80277

19 Sulfate 40 0.02201 0.069480 5.66875 -0.02668 40 0.40747 0.054807 -3.76473 -0.01649 1.35963

20 Carbonate 40 0.00793 0.026707 4.47290 -0.00611 40 0.08175 0.026039 2.89739 -0.00441 0.22707

21 Sodium +K 40 0.07696 0.060765 4.94427 -0.04490 40 0.17398 0.058255 0.68378 -0.04030 0.61406

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 37 0.99320 0.038850 0.55166 0.98788 36 0.99459 0.035665 -3.90892 0.98520 0.65566

23 Calcium 37 0.00046 0.051289 4.32410 -0.00231 36 0.01477 0.052224 2.77970 -0.00361 0.22740

24 Magnesium 37 0.00055 0.052098 3.23358 -0.00257 36 0.00298 0.053587 3.88839 -0.00214 -0.09630

25 Chloride 37 0.00075 0.045330 4.38794 -0.00262 36 0.24139 0.040668 -1.26986 -0.00610 0.83173

26 Sulfate 37 0.01480 0.060564 5.52729 -0.01562 36 0.16654 0.057326 -0.52014 -0.01927 0.88893

27 Carbonate 37 0.00059 0.043751 4.43636 -0.00223 36 0.00840 0.044868 5.42176 -0.00155 -0.14494

28 Sodium +K 37 0.05196 0.068714 4.80861 -0.03386 36 0.30823 0.060013 -4.23450 -0.03897 1.32891
113 

19. STATION 09427520 (PARKER) Colorado River below Parker Dam, AZCA 

 

STATION 09427520 Colorado River below Parker Dam, AZ UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 81 0.0 0.0

2 2009 81 0.0 0.0

3 2010 81 0.0 0.0

4 2011 75 0.0 0.0

5 2012 75 0.0 0.0

 

STATION 09427520 Colorado River below Parker Dam, AZ UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 81 0.99474 0.039218 0.58160 0.99384 81 0.99804 0.024067 -5.78481 0.99589 0.91687

2 Calcium 81 0.01208 0.056721 4.22505 0.01156 81 0.27230 0.048992 -1.73744 0.01347 0.85870

3 Magnesium 81 0.00690 0.092536 3.46413 -0.01422 81 0.49759 0.066239 -9.85848 -0.00993 1.91869

4 Chloride 81 0.00132 0.050325 4.51549 -0.00337 81 0.38714 0.039675 -1.89128 -0.00131 0.92269

5 Sulfate 81 0.00303 0.050419 5.55281 -0.00513 81 0.59542 0.032324 -2.40753 -0.00257 1.14643

6 Carbonate 81 0.00279 0.035927 4.36534 0.00350 81 0.17494 0.032888 1.30793 0.00449 0.44032

7 Sodium +K 81 0.11282 0.050874 4.91004 -0.03343 81 0.18461 0.049085 1.94604 -0.03248 0.42687

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 81 0.99474 0.039218 0.58160 0.99384 81 0.99804 0.024067 -5.78481 0.99589 0.91687

9 Calcium 81 0.01208 0.056721 4.22505 0.01156 81 0.27230 0.048992 -1.73744 0.01347 0.85870

10 Magnesium 81 0.00690 0.092536 3.46413 -0.01422 81 0.49759 0.066239 -9.85848 -0.00993 1.91869

11 Chloride 81 0.00132 0.050325 4.51549 -0.00337 81 0.38714 0.039675 -1.89128 -0.00131 0.92269

12 Sulfate 81 0.00303 0.050419 5.55281 -0.00513 81 0.59542 0.032324 -2.40753 -0.00257 1.14643

13 Carbonate 81 0.00279 0.035927 4.36534 0.00350 81 0.17494 0.032888 1.30793 0.00449 0.44032

14 Sodium +K 81 0.11282 0.050874 4.91004 -0.03343 81 0.18461 0.049085 1.94604 -0.03248 0.42687
114 

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 81 0.98864 0.044529 0.55570 0.99282 81 0.99583 0.027150 -7.88084 1.00310 1.21063

16 Calcium 81 0.04809 0.061740 4.00742 0.03316 81 0.49714 0.045160 -6.09113 0.04546 1.44913

17 Magnesium 81 0.06930 0.070970 3.69810 -0.04628 81 0.44861 0.054975 -7.09172 -0.03313 1.54833

18 Chloride 81 0.00694 0.048452 4.54170 -0.00968 81 0.21307 0.043407 -0.71530 -0.00327 0.75437

19 Sulfate 81 0.00767 0.063298 5.57736 -0.01330 81 0.55905 0.042464 -5.65922 0.00039 1.61244

20 Carbonate 81 0.05255 0.028688 4.24545 0.01615 81 0.06169 0.028732 3.57457 0.01696 0.09627

21 Sodium +K 81 0.07541 0.060394 4.94778 -0.04122 81 0.36710 0.050287 -3.13064 -0.03137 1.15924

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 75 0.99366 0.033669 0.50404 0.99570 75 0.99574 0.027769 -6.08101 1.00451 0.94679

23 Calcium 75 0.04648 0.049099 4.05899 0.02561 75 0.07705 0.048640 1.06141 0.02963 0.43099

24 Magnesium 75 0.10203 0.059491 3.67510 -0.04739 75 0.15804 0.058004 -1.39067 -0.04061 0.72835

25 Chloride 75 0.00070 0.044878 4.45566 -0.00280 75 0.05771 0.043880 0.80102 0.00209 0.52546

26 Sulfate 75 0.00124 0.051726 5.45748 -0.00432 75 0.28967 0.043925 -4.02002 0.00837 1.36267

27 Carbonate 75 0.05698 0.030842 4.23400 0.01792 75 0.10713 0.030218 6.65894 0.01467 -0.34866

28 Sodium +K 75 0.05608 0.061324 4.86620 -0.03532 75 0.36292 0.050728 -7.05492 -0.01937 1.71401

20. STATION 09429490 (IMPER) Colorado River above Imperial Dam, AZ-CA 

STATION 09429490 Colorado River above Imperial Dam, AZ UPDATE 2012 

SUMMARY OF QW OBSERVATIONS, BY 3-YEAR SLIDING GROUP 

Obs 

WATER

YEAR

# OF QW

OBSV.

% P70300

SUBST.

% P00060

SUBST.

1 2008 122 0.0 0.0

2 2009 122 0.0 0.0

3 2010 113 0.0 0.0

4 2011 74 0.0 0.0

5 2012 74 0.0 0.0

STATION 09429490 Colorado River above Imperial Dam, AZ UPDATE 2012 

REGRESSION STATISTICS, BY 3-YEAR SLIDING GROUPS 

REGRESSION #1: VARIABLE = e**A * DISCHARGE**B 

REGRESSION #2: VARIABLE = e**C * DISCHARGE**D * COND**E 

VARIABLE=(mg/L), except for SALT LOAD (tons/day) 

DISCHARGE=(cfs) COND=(uMHOS/cm) 
115 

2008 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

1 SALT LOAD 122 0.96696 0.043285 1.75685 0.87780 122 0.98722 0.027032 -5.43980 0.99096 0.87572

2 Calcium 122 0.14503 0.056468 5.20661 -0.08718 122 0.31378 0.050801 -0.11973 -0.00342 0.64813

3 Magnesium 122 0.04985 0.089912 4.11846 -0.07720 122 0.36982 0.073531 -6.95946 0.09699 1.34801

4 Chloride 122 0.42289 0.055622 6.27387 -0.17848 122 0.74637 0.037028 -2.56759 -0.03945 1.07587

5 Sulfate 122 0.24441 0.047309 6.53250 -0.10086 122 0.61262 0.034016 -0.47921 0.00940 0.85322

6 Carbonate 122 0.43648 0.031159 5.43525 -0.10279 122 0.75320 0.020707 0.47554 -0.02480 0.60352

7 Sodium +K 122 0.40693 0.058836 6.41807 -0.18268 122 0.58218 0.049590 -0.37242 -0.07591 0.82630

2009 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

8 SALT LOAD 122 0.96696 0.043285 1.75685 0.87780 122 0.98722 0.027032 -5.43980 0.99096 0.87572

9 Calcium 122 0.14503 0.056468 5.20661 -0.08718 122 0.31378 0.050801 -0.11973 -0.00342 0.64813

10 Magnesium 122 0.04985 0.089912 4.11846 -0.07720 122 0.36982 0.073531 -6.95946 0.09699 1.34801

11 Chloride 122 0.42289 0.055622 6.27387 -0.17848 122 0.74637 0.037028 -2.56759 -0.03945 1.07587

12 Sulfate 122 0.24441 0.047309 6.53250 -0.10086 122 0.61262 0.034016 -0.47921 0.00940 0.85322

13 Carbonate 122 0.43648 0.031159 5.43525 -0.10279 122 0.75320 0.020707 0.47554 -0.02480 0.60352

14 Sodium +K 122 0.40693 0.058836 6.41807 -0.18268 122 0.58218 0.049590 -0.37242 -0.07591 0.82630

2010 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std. 

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

15 SALT LOAD 113 0.96449 0.042476 2.09477 0.83783 113 0.99295 0.019008 -7.17582 1.01504 1.09186

16 Calcium 113 0.17852 0.058986 5.34903 -0.10407 113 0.48758 0.046798 -3.47111 0.06454 1.03881

17 Magnesium 113 0.20232 0.073200 4.64248 -0.13952 113 0.51975 0.057055 -6.61444 0.07566 1.32581

18 Chloride 113 0.53137 0.054976 6.63693 -0.22155 113 0.79936 0.036136 -3.49783 -0.02782 1.19364

19 Sulfate 113 0.43121 0.048341 7.02984 -0.15930 113 0.77991 0.030207 -2.19725 0.01708 1.08674

20 Carbonate 113 0.47107 0.030391 5.47924 -0.10854 113 0.72525 0.022002 0.34336 -0.01037 0.60489

21 Sodium +K 113 0.46339 0.059482 6.63838 -0.20919 113 0.68973 0.045435 -2.77921 -0.02917 1.10918

2011 

Obs VARIABLE 

#1 

obsv. 

R-square 

#1 

Std.

Error A B

#2

obsv.

R-square

#2

Std. 

Error C D E

22 SALT LOAD 74 0.96985 0.040981 2.24272 0.81885 74 0.99483 0.017096 -7.88208 1.02962 1.17383

23 Calcium 74 0.25602 0.054008 5.39717 -0.11161 74 0.46188 0.046255 -2.31460 0.04892 0.89407

24 Magnesium 74 0.30203 0.063125 4.66607 -0.14629 74 0.56724 0.050054 -5.89642 0.07359 1.22457

25 Chloride 74 0.59504 0.057370 6.82831 -0.24500 74 0.83238 0.037170 -5.09383 0.00318 1.38221

26 Sulfate 74 0.55044 0.046033 7.17922 -0.17945 74 0.82981 0.028522 -2.67126 0.02561 1.14203

27 Carbonate 74 0.53353 0.034516 5.67134 -0.13004 74 0.78950 0.023349 -1.26909 0.01443 0.80465

28 Sodium +K 74 0.54324 0.060148 6.81818 -0.23109 74 0.76322 0.043610 -4.51247 0.00478 1.31363
116 
117 
118 

Site Short 

Name Coefficient Standard Error Coefficient Standard Error Coefficient Standard Error Model p-value PRESS statistic Adjusted R2 N

09071750 Colorado River above Glenwood Springs, CO Glen -7.487 0.584 1.056 0.031 1.093 0.056 <0.0001 0.061 0.994 66 09095500 Colorado River near Cameo, CO Cameo -5.263 0.816 0.927 0.043 0.906 0.070 <0.0001 0.029 0.995 50 09152500 Gunnison River near Grand Junction, CO Gunn -6.899 0.218 0.988 0.011 1.104 0.022 <0.0001 0.059 0.993 61 09180000 Dolores River near Cisco, UT Dolor -6.030 0.196 0.969 0.011 0.967 0.020 <0.0001 0.263 0.991 91 09180500 Colorado River near Cisco, UT Cisco -6.486 0.391 1.005 0.021 1.060 0.032 <0.0001 0.053 0.989 88 09217000 Green River near Green River WY Grwy -6.865 0.149 0.981 0.006 1.099 0.019 <0.0001 0.109 0.996 132 09251000 Yampa River near Maybell, CO Yampa -7.287 0.088 1.017 0.004 1.124 0.012 <0.0001 0.073 0.999 66 09302000 Duchesne River near Randlett, UT Duch -6.632 0.189 0.991 0.009 1.049 0.021 <0.0001 0.204 0.996 91 09306500 White River near Watson, UT White 1.901 0.161 0.704 0.025 na na <0.0001 2.342 0.908 82 09315000 Green River at Green River, UT Grut 2.746 0.190 0.680 0.022 na na <0.0001 2.655 0.917 85 09328500 San Rafael River near Green River, UT SanRaf 3.118 0.087 0.599 0.021 na na <0.0001 7.029 0.902 88 09379500 San Juan River near Bluff, UT Bluff -7.302 0.125 1.013 0.008 1.132 0.013 <0.0001 0.098 0.995 88 09380000 Colorado River at Lees Ferry, AZ Lees -7.758 0.375 1.028 0.010 1.164 0.054 <0.0001 0.009 0.996 44 

09402500 Colorado River near Grand Canyon, AZ Grcan 0.060 0.315 1.011 0.033 na na <0.0001 0.113 0.957 34 09415000 Virgin River at Littlefield, AZ Virgin 3.664 0.144 0.592 0.030 na na <0.0001 0.186 0.924 34 09421500 Colorado River below Hoover Dam, AZ-NV Hoover -5.430 0.619 0.990 0.007 0.872 0.088 <0.0001 0.151 0.993 144 09427520 Colorado River below Parker Dam, AZ-CA Parker -7.427 0.402 1.002 0.004 1.146 0.057 <0.0001 0.226 0.996 301 09429490 Colorado River above Imperial Dam, AZ-CA Imper -7.248 0.230 1.015 0.006 1.102 0.027 <0.0001 0.140 0.993 399 

Table B1. Salinity load regression model coefficients and statistical diagnostics at selected U.S. Geological Survey streamflow-gaging stations within the Colorado River Basin.

U.S. 

Geological 

Survey 

streamflowgaging

Site name

Y-axis intercept Streamflow Specific Conductance Statistic

K2,TK12

KK2T2 ,,TK K 123

K2,TK12

KK2T2 ,,TK K 123

K2,TK12

KK2T2 ,,TK K 123

K2,TK12

KK2T2 ,,TK K 123
119 

APPENDIX C 

20 Station Flow and Salt over Time
120 

Figure C1 – Flow and TDS over time for sites 1-4.
121 

Figure C2 - Flow and TDS over time for sites 5-8.
122 

Figure C3 - Flow and TDS over time for sites 9-12.
123 

Figure C4 - Flow and TDS over time for sites 13-16.
124 

0

500

1,0001,5002,000

500

1,0001,5002,0002,500

Flow 1,000 (ac-ft)

TDS (mg/L)

Virgin River at Littlefield, Arizona

TDSFlow 

400500600700800900

TDS (mg/L)

Colorado River below Hoover 

TDSFlow 

0

10,00020,00030,00040,000

500600700800900

Flow 1,000 (ac-ft)

TDS (mg/L)

Colorado River below Parker Dam, Ariz-Calif

TDSFlow 

550650750850950

TDS (mg/L)

Colorado River at Imperial Da

TDSFlow 

Figure C5 - Flow and TDS over time for sites 17-20.