Chemical Results for Bottom Material for DOI Irrigation and Drainage Task 

Group Studies, 1988-1989

T.F. Harms

K.C. Stewart

P.H. Briggs

P.L. Hageman

C.S.E. Papp

Introduction

	In response to Congressional requests, the Department of the 
Interior (DOI) formed a multi-agency task group in the fall of 1985 to examine 
the potential for damage to lands affected by DOI irrigation projects. The 
objective of the task group is to determine from existing information and 
reconnaissance studies if irrigation practices have the potential to cause 
harmful effects on human health, fish, wildlife, and other water users, or 
to reduce the suitability of water for beneficial uses.

	In 1988, field-screening studies were conducted at ten areas in 
the western U.S. where wildlife management areas receive irrigation drainage 
water from federally managed irrigation projects. The field-screening 
studies were designed as limited-sampling, reconnaissance-level investigations 
whose purposes are to recognize problem areas and problem elements, but not to 
characterize areas in detail. Following are brief descriptions of the ten 
areas:

Belle Fourche, South Dakota: The study area consists of about 57,000 acres 
of irrigable land near the northeastern edge of the Black Hills in western 
South Dakota. The lands are generally along the Belle Fourche River in an area 
approximately 12 miles wide and extending 24 miles downstream from the Belle 
ourche Diversion Dam and Reservoir.

Angostura, South Dakota: The study area extends along the Cheyenne River for 
about 24 miles below Angostura Dam in Fall River and Custer Counties in 
southwestern South Dakota. Approximately 12,200 acres of land are irrigated; 
irrigation tail-water and ground-water return form a majority of the flow in 
the Cheyenne River in the project area during portions of the year.

American Falls Reservoir, Idaho: The reservoir is located on the Snake River 
in southeastern Idaho. As a portion of its inflow, it receives irrigation 
drainage water from about 560,000 acres of irrigated land and effluent from 
municipalities. Mini-doka National Wildlife Refuge (NWR) is located about 10 
miles downstream of the reservoir.

Riverton, Wyoming: The study area is located in Fremont County in west-central 
Wyoming. Water from the Wind River is diverted for irrigating approximately 
70,000 acres. Extensive fisheries, waterfowl nesting areas, and refuges have 
been developed in the project area by the state.

Middle Arkansas River, Colorado: The study area extends about 250 miles from 
Pueblo Reservoir near Pueblo, Colorado, to Finney County in western Kansas. 
The study area includes several state-operated wildlife areas with 
reservoirs that are heavily used by migratory waterfowl.

Gunnison River and Sweitzer Lake, Colorado: The study area includes parts of 
the Gunnison River basin and the Uncompahgre River basin in west-central 
Colorado; currently about 66,000 acres in the valley are irrigated. Also 
included in the study area is Sweitzer Lake, a Colorado state park that has 
been previously reported to contain high levels of selenium in biota, water, 
and bottom sediment.

Middle Rio Grande River, New Mexico: The study area extends about 40 miles 
along the Rio Grande River from San Acacia to San Marcial in Socorro County, 
New Mexico. The primary focus of the study is the Bosque del Apache NWR 
which contains 57,200 acres and is managed primarily for migratory birds, 
including a small experimental flock of whooping cranes.

Malheur National Wildlife Refuge, Oregon: The study area is located within a 
closed basin in southeastern Oregon. The refuge covers 184,000 acres and is 
one of the largest inland marshes in the United States.

Klamath Basin Refuge Complex, California: The study area is the upper 
Klamath River basin straddling the Oregon-California border. Upper Klamath 
NWR, Shoalwater Bay WMA (Wildlife Management Area), Squaw Point WMA, Clear 
Lake NWR, Lower Klamath Lake NWR, and Tule Lake NWR are all included in the 
study area. Lower Klamath Lake NWR and Tule NWR are the terminus for most 
agricultural drain water in the basin.

Sacramento Refuge Complex, California: The study area is located in the 
central portion of the Sacramento Valley. The refuge complex consists of 
five individual refuges--Delevan NWR, Colusa NWR, Butte Sink NWR, Sacramento 
NWR, and Sutter NWR. Levels of Se that exceed the EPA (Environmental 
Protection Agency) drinking-water standard are associated with the 
Sacramento refuge complex.

	In addition, samples were received from three areas identified 
by 1986-87 reconnaissance studies as needing additional sampling to define 
potential problems. These are: 

Kendrick Reclamation Project, Wyoming: The study area is located just west 
of Casper, Wyoming, in Natrona County. Approximately 200 square miles lie 
within the project area, although only 24,000 acres are irrigated for crop 
production. Elevated concentrations of selenium (up to 25 ppm in lake 
sediments) were found during the reconnaissance study.

Stillwater Wildlife Management Area (WMA), Nevada: The study area is part of 
the lower Carson River basin in Churchill County; it includes the Stillwater 
NWR and the Stillwater WMA. Mercury levels in bottom sediments as high as 18 
ppm were observed in the reconnaissance study.

Middle Green River, Utah: The study area is located south of Vernal, Utah, and 
adjacent to the Green River. Selenium concentrations of up to 85 ppm were 
found in bottom sediments during the reconnaissance study. 

	The field-screening studies were conducted by personnel from the 
Department of the Interior, U.S. Geological Survey, Bureau of Reclamation,U.S. 
Fish and Wildlife Service, and other federal or state agencies as appropriate. 
The media sampled consisted of surface water, plant tissue, animal tissue, and 
bottom sediments from lakes and streams. This report presents only the results 
of the analyses of the bottom sediments.