Central Columbia Plateau - Yakima River Basin NAWQA Study -- Publications
YES. Many agricultural pesticides are present at very low concentrations. No pesticides were found at concentrations above regulatory drinking water standards, but some were at concentrations that exceeded guidelines for the protection of aquatic life (freshwater-chronic criteria) or health advisories for drinking water.
Land-use map of the Central Columbia Plateau (GIF, 85460 bytes)
Surface-water sites representing four drainage basins with different farming practices were sampled by the U.S. Geological Survey as part of its National Water-Quality Assessment Program. Samples were taken one to five times a month from March 1993 through May 1994. Detections of pesticides usually, but not always, were related to pesticides used on crops in the drainage basins.
Of the 84 compounds targeted for analysis, 45 compounds were detected. No pesticides were found at concentrations that exceeded U.S. Environmental Protection Agency (USEPA) maximum contaminant levels for drinking water, but concentrations of dieldrin and alpha-HCH exceeded their USEPA health advisories for drinking water. Five pesticides were at concentrations that could adversely affect aquatic life.
Table 1.--Pesticides that exceeded freshwater-chronic criteria for the protection of aquatic life ------------------------------------------------------------------------------- Number of samples that exceed criteria at: ----------------------------------------------------- Pesticide (trade name) EL68D Crab Creek Upper Crab Palouse Wasteway Lateral Creek River Chlorpyrifos (Lorsban) 3 3 -- -- Azinphos-methyl (Guthion) 3 12 1 -- Carbaryl (Sevin) 0 2 0 -- Diazinon (several) 3 1 -- 1 Triallate (Far-Go) -- -- 1 3 (Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey.) -------------------------------------------------------------------------------
Application rates--Irrigated agriculture (GIF, 23062 bytes)
Application rates--Dryland agriculture (GIF, 22188 bytes)
Highest concentrations of pendimethalin were detected
during or shortly after the period when it is typically applied.
The presence of atrazine during low streamflows
(November to mid-March) indicates that the ground
water is one source of atrazine to the surface water.
Detections of gamma-HCH (Lindane) coincide
with periods of surface runoff.
USGS Fact Sheet 241-95
Prepared by R.J. Wagner, J.C. Ebbert, and L.M. Roberts
July, 1996
Anderson, J.E., and Gianessi, L., 1995, Pesticide use in the Central Columbia Plateau: Washington, D.C., National Center for Food and Agricultural Policy, misc. pagination.
Nowell, L.H., and Resek, E.A., 1994, Summary of National Standards and Guidelines for pesticides in water, bed sediment, and aquatic organisms and their applications to water-quality assessments: U.S. Geological Survey Open- File Report 94-44, 115p.
Wagner, R.J., Ebbert, J.C., Roberts, L.M., and Ryker, S.J., in press, Agricultural pesticide applications and observed concentrations in surface waters from four drainage basins in the Central Columbia Plateau, Washington and Idaho, 1993-94: U.S. Geological Survey Water-Resources Investigations Report 95-4285, [about 50] p.
For further information, contact:
Project Chief
CCYK NAWQA
1201 Pacific Ave., Suite 600
Tacoma, WA 98402
Phone:(253) 593-6530 ext 2687; -6514 fax
Email: rwblack@usgs.gov
Suggested citation:
Wagner, R.J., Ebbert, J.C., and Roberts, L.M., 1995, Are agricultural pesticides in the surface waters of the Central Columbia Plateau?: U.S. Geological Survey Fact Sheet 241-95, on line at <URL http://wa.water.usgs.gov/ccpt/pubs/fs-241-95.html>, accessed October 17, 1997.
For a paper copy of this report, send Email to rwblack@usgs.gov