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NIWQP Project/Study Area—
NIWQP Freezeout Lake Area - Sun River Project, Montana
LocationThe Sun River study area is located within Cascade, Chouteau, and Teton counties of west-central Montana. (Detail map).
StatusFreezeout Lake Wildlife Management Area (WMA) receives drainage from adjacent irrigated land, Sun River Project.
Results of a 1986 reconnaissance study and a 1990-92 detailed study indicated that some selenium concentrations in water, bottom sediment, and biota in Freezeout Lake WMA wetlands were higher than established criteria and standards, raising concerns about potential toxicity to aquatic organisms and water birds. In 1994-95, a second detailed study was conducted to determine the distribution, mobilization, and accumulation of selenium associated with irrigation drainage from land underlain by glacial-lake deposits in the southern part of the Freezeout Lake WMA.
Freezeout Lake WMA is bordered on the south and east by seleniferous glacial-lake deposits. Precipitation and selenium-free irrigation water infiltrate the deposits and dissolve and mobilize selenium. Selenium-rich ground water then discharges into open irrigation drains. The irrigation drains discharge into wetlands of Freezeout Lake and Pond 5 in Freezeout Lake WMA. In the wetlands, selenium is removed from water and accumulates in bottom sediment and biota.
Biota samples typically had higher selenium concentrations than national average background concentrations. Concentration increases from water and bottom sediment to biota, and from lower to higher trophic levels, indicate that selenium is bioaccumulating. In addition, most invertebrate and fish samples collected from irrigation drains that convey water from glacial-lake deposits, and from wetlands at the mouths of those drains, had selenium concentrations that exceeded the critical threshold concentration for water-fowl dietary ingestion of 5 micrograms per gram dry weight. However, no overt indications of reproductive impairment were observed in water birds nesting near the drains and wetlands. Embryo viability, as well as nest and hatching success rates were within the expected range for healthy populations. Likewise, reproductive impairment was not evident in brook stickleback fish, based on their abundance in the drains.
Although irrigation water is not the source of selenium, irrigation of seleniferous soils near Freezeout Lake has mobilized naturally occurring selenium from glacial-lake deposits and made it biologically available, primarily in irrigation drains and in wetlands at the mouths of drains. Ongoing efforts to conserve irrigation water will reduce irrigation drainage and potentially could decrease biological exposure to selenium by reducing selenium loading to wetlands, but could concurrently increase selenium concentrations in irrigation drains.
A moderate effort is planned to periodically collect data, determine trends, and assess impacts to biota. This work is planned after fiscal year 2003, subject to availability of funds.
Phases 2 and 3 DataChemical Data From Water:
ASCII - 264 KB .dat File or Microsoft Excel - 935 KB .xls File
ASCII - 14 KB .dat File or Microsoft Excel - 71 KB .xls File
ASCII - 219 KB .dat File or Microsoft Excel - 756 KB .xls File
ASCII - 9 KB .dat File or Microsoft Excel - 34 KB .xls File
Project Specific ReportsKendy, E., Nimick, D.A., Maloy, J.C., and Olsen, B., Detailed Study of Selenium in Glacial-Lake Deposits, Wetlands, and Biota Associated with Irrigation Drainage in the Southern Freezeout Lake Area, West-Central Montana, 1994-95: U.S. Geological Survey Water-Resources Investigations Report 99-4019, 51 p.
Kendy, E., Olsen, B., and Malloy J.C., 1998, Field Screening of Water Quality, Bottom Sediment, and Biota Associated with Irrigation Drainage in the Helena Valley, West-Central Montana, 1995: U.S. Geological Survey Water-Resources Investigations Report 97-4214, 62 p.
Kendy, E. and Olsen, B., 1997, Physical, Chemical, and Biological Data Associated with Irrigation Drainage in the Freezeout Lake area, West-Central Montana, 1994-95: U.S. Geological Survey Open-File Report 97-349, 48 p.
Related DocumentsNimick, D.A., Lambing, J.H., Palawski, D.U., and Malloy, J.O., 1996, Detailed study of selenium in soil, water, bottom sediment and biota in the Sun River Irrigation Project, Freezout Lake Wildlife Management Area, and Benton Lake National Refuge, west-central Montana, 1990-1992: U.S. Geological Survey Water-Resources Investigations Report 95- 4170, 120 p.
Lambing, J.H., Nimick, DA, Knapton, J.R., And Palawski, D.U., 1994, Physical, chemical, and biological data for detailed study of the Sun River Irrigation Project, Freezout Lake Wildlife Management Area, and Benton Lake National Wildlife Refuge, west-central Montana, 1990-92, with selected data for 1987-89: US Geological Survey Open-File Report 94-120, 171 p.
Nimick, DA, Lambing, J.H., And Palawski, D.U., 1993, Selenium in soil, water, sediment, and biota of the lower Sun River area, west-central Montana: in Allen, R.G., And Neale, C.M.U., eds., Management of irrigation and drainage systems: integrated perspectives: American Society of Civil Engineers, Proceedings of the 1993 National Conference on Irrigation and Drainage Engineering, Park City, Utah, July 21-23, 1993, p. 762-769.
Knapton, J.R., Jones, W.E., And Sutphin, J.W., 1988, Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Sun River area, west-central Montana, 1986-87: US Geological Survey Water-Resources Investigations Report 87-4244, 78 p.
Freezeout Lake Study Team Members (Montana)Dave Nimick, USGS
Karen Nelson, FWS
Richard Blaskovich, USBR