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Irrigation Drainage Studies of the Angostura Reclamation Unit and the Belle Fourche Reclamation Project, Western South Dakota: Results of 1994 Sampling and Comparisons with 1988 Data

By Steven K. Sando, Joyce E. Williamson, Kimberly K. Dickerson, and Edwin A. Wesolowski

Water-Resources Investigations Report 01-4103

Prepared in cooperation with U.S. Fish and Wildlife Service
and the Bureau of Reclamation


The U.S. Department of the Interior started the National Irrigation Water Quality Program in 1985 to identify the nature and extent of irrigation-induced water-quality problems that might exist in the western U.S. The Angostura Reclamation Unit (ARU) and Belle Fourche Reclamation Project (BFRP) in western South Dakota were included as part of this program. The ARU and BFRP reconnaissance studies were initiated in 1988, during below-normal streamflow conditions in both study areas. Surface water, bottom sediment, and fish were resampled in 1994 at selected sites in both study areas during generally near-normal streamflow conditions to compare with 1988 study results.

Concentrations of major ions in water for both the ARU and BFRP study areas are high relative to national baseline levels. Major-ion concentrations for both areas generally are lower for 1994 than for 1988, when low-flow conditions prevailed, but ionic proportions are similar between years. For ARU, dissolved-solids concentrations probably increase slightly downstream from Angostura Reservoir; however, the available data sets are insufficient to confidently discern effects of ARU operations on dissolved-solids loading. For BFRP, dissolved-solids concentrations are slightly higher at sites that are affected by irrigation drainage; again, however, the data are inconclusive to determine whether BFRP operations increase dissolved-solids loading.

Most trace-element concentrations in water samples for both study areas are similar between 1988 and 1994, and do not show strong relations with discharge. ARU operations probably are not contributing discernible additional loads of trace elements to the Cheyenne River. For BFRP, concentrations of some trace elements are slightly higher at sites downstream from irrigation operations than at a site upstream from irrigation operations. BFRP operations might contribute to trace-element concentrations in the Belle Fourche River, but available data are insufficient to quantify increases. For both study areas, concentrations of several trace elements occasionally exceed National Irrigation Water Quality Program guidelines. Selenium routinely occurs in concentrations that could be problematic at sites upstream and downstream from both study areas. Elevated selenium concentrations at sites upstream from irrigation operations indicate that naturally occurring selenium concentrations are relatively high in and near the study areas. While ARU operations probably do not contribute discernible additional loads of selenium to the Cheyenne River, BFRP operations might contribute additional selenium loads to the Belle Fourche River.

Concentrations of most trace elements in bottom sediment, except arsenic and selenium, are similar to typical concentrations for western U.S. soils for both study areas. Bottom-sediment arsenic and selenium (1988) concentrations in both study areas can reach levels that might be of concern; however, there is insufficient information to determine whether irrigation operations contribute to these elevated concentrations.

Concentrations of most trace elements in fish in both study areas are less than values known to adversely affect fish or birds, although there are occasional exceedances of established criteria. However, selenium concentrations in fish samples routinely are within the National Irrigation Water Quality Program level of concern, and also commonly exceed the dietary guideline for avian consumers for both study areas. Selenium concentrations in fish samples generally are higher at sites downstream from irrigation operations. For BFRP, arsenic and mercury concentrations are elevated in fish samples from site B-18, which is influenced by mine tailings.




Description of the Study Areas

Sampling Sites and Methods

Streamflow Conditions

Comparison of Results

Angostura Reclamation Unit

Water Quality



Synopsis of Results for the Angostura Reclamation Unit

Belle Fourche Reclamation Project

Water Quality



Synopsis of Results for the Angostura Reclamation Unit

Summary and Conclusions


Supplemental Information

This report is available online in Portable Document Format (PDF). If you do not have the Adobe Acrobat PDF Reader, it is available for free download from Adobe Systems Incorporated.

Download the Report (PDF, 3.2MB).

Document Accessibility: Adobe Systems Incorporated has information about PDFs and the visually impaired. This information provides tools to help make PDF files accessible. These tools convert Adobe PDF documents into HTML or ASCII text, which then can be read by a number of common screen-reading programs that synthesize text as audible speech. In addition, an accessible version of Acrobat Reader 5.0 for Windows (English only), which contains support for screen readers, is available. These tools and the accessible reader may be obtained free from Adobe at Adobe Access.

Send questions or comments about this report to the author, S.K. Sando (605) 352-4241 ext. 230.

For more information about USGS activities in South Dakota, visit the USGS South Dakota District home page.

U.S. Department of the Interior, U.S. Geological Survey
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Last modified: Wednesday, December 07 2016, 01:18:17 PM
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