Wyoming's groundwater and streams are routinely monitored for pesticides. In order to balance the use of pesticides (herbicides, insecticides, and fungicides) with the protection of water resources, the Wyoming Department of Agriculture began a project to sample groundwater in 1995, in cooperation with the U.S. Geological Survey. Since the project's inception, more than 750 samples from groundwater and, recently streams, have been collected across Wyoming and analyzed for up to 165 pesticides and their breakdown products. No sample collected has had a pesticide detected at a concentration exceeding drinking-water standards.
Groundwater sampling results:
- Nearly 700 groundwater samples from nearly 350 wells have been collected since 1995.
- Samples have been collected from wells in every county in Wyoming.
- Baseline samples were collected at sites where groundwater was deemed to be the most vulnerable to human activities, so results from this project describe the groundwater where pesticides are most likely to be detected.
- Two-thirds of the pesticides or breakdown products that were screened for were never detected.
- Herbicides were detected more often than insecticides, and fungicides were not detected in groundwater.
- Four of the nearly 165 pesticides analyzed for were found more frequently in groundwater: prometon (trade name Pramitol), atrazine (trade name Aatrex), simazine (trade name Princep), tebuthiuron (trade name Spike).
- Water from wells that were located in urban areas tended to have pesticides detected more frequently than wells located in agricultural areas.
- Water from wells in agricultural areas tended to have a wider variety of pesticides detected.
Surface-water sampling results:
- Around 60 samples from 19 different streams and rivers have been collected since 2006.
- Three-quarters of the pesticides or breakdown products that were screened for were never detected.
- Herbicides were detected more often than insecticides or fungicides.
- Four of the nearly 140 pesticides analyzed for were found more frequently in surface water: glyphosate (trade name Roundup), 2,4-D (trade name Dacamine), 2,4-DB (trade name Butoxone), and prometon (trade name Pramitol)
- Streams and rivers in areas with agricultural activities tended to have pesticides detected more frequently than in areas with other land uses.
Water-quality results of pesticide sampling can be found for all samples collected for this project using the following links
Wyoming Pesticide Surface-Water Sampling Sites
Wyoming Pesticide Surface-Water Sampling Sites
Southeastern Wyoming Pesticide Groundwater Sampling Sites
Southeastern Wyoming Pesticide Groundwater Sampling Sites
Northeastern Wyoming Pesticide Groundwater Sampling Sites
Northeastern Wyoming Pesticide Groundwater Sampling Sites
Northwestern Wyoming Pesticide Groundwater Sampling Sites
Northwestern Wyoming Pesticide Groundwater Sampling Sites
Southwestern Wyoming Pesticide Groundwater Sampling Sites
Southwestern Wyoming Pesticide Groundwater Sampling Sites
Below are publications associated with this project.
Pesticides in Wyoming Groundwater, 2008-10
Pesticides in Wyoming's rivers, 2006-10
Occurrence of Pesticides in Ground Water of Wyoming, 1995-2006
Pesticides in Ground Water of Wyoming, 1995-2006
Pesticides in surface water in the Bighorn River and North Platte River basins, Wyoming, 2006
Below are partners associated with this project.
- Overview
Wyoming's groundwater and streams are routinely monitored for pesticides. In order to balance the use of pesticides (herbicides, insecticides, and fungicides) with the protection of water resources, the Wyoming Department of Agriculture began a project to sample groundwater in 1995, in cooperation with the U.S. Geological Survey. Since the project's inception, more than 750 samples from groundwater and, recently streams, have been collected across Wyoming and analyzed for up to 165 pesticides and their breakdown products. No sample collected has had a pesticide detected at a concentration exceeding drinking-water standards.
Groundwater sampling results:
Locations of wells sampled for baseline sampling during 1995-2006. Well locations are shown in red when pesticide detected.(Public domain.) - Nearly 700 groundwater samples from nearly 350 wells have been collected since 1995.
- Samples have been collected from wells in every county in Wyoming.
- Baseline samples were collected at sites where groundwater was deemed to be the most vulnerable to human activities, so results from this project describe the groundwater where pesticides are most likely to be detected.
- Two-thirds of the pesticides or breakdown products that were screened for were never detected.
- Herbicides were detected more often than insecticides, and fungicides were not detected in groundwater.
- Four of the nearly 165 pesticides analyzed for were found more frequently in groundwater: prometon (trade name Pramitol), atrazine (trade name Aatrex), simazine (trade name Princep), tebuthiuron (trade name Spike).
- Water from wells that were located in urban areas tended to have pesticides detected more frequently than wells located in agricultural areas.
- Water from wells in agricultural areas tended to have a wider variety of pesticides detected.
Surface-water sampling results:
- Around 60 samples from 19 different streams and rivers have been collected since 2006.
- Three-quarters of the pesticides or breakdown products that were screened for were never detected.
- Herbicides were detected more often than insecticides or fungicides.
- Four of the nearly 140 pesticides analyzed for were found more frequently in surface water: glyphosate (trade name Roundup), 2,4-D (trade name Dacamine), 2,4-DB (trade name Butoxone), and prometon (trade name Pramitol)
- Streams and rivers in areas with agricultural activities tended to have pesticides detected more frequently than in areas with other land uses.
- Data
Water-quality results of pesticide sampling can be found for all samples collected for this project using the following links
Wyoming Pesticide Surface-Water Sampling Sites
Wyoming Pesticide Surface-Water Sampling Sites
Southeastern Wyoming Pesticide Groundwater Sampling Sites
Southeastern Wyoming Pesticide Groundwater Sampling Sites
Northeastern Wyoming Pesticide Groundwater Sampling Sites
Northeastern Wyoming Pesticide Groundwater Sampling Sites
Northwestern Wyoming Pesticide Groundwater Sampling Sites
Northwestern Wyoming Pesticide Groundwater Sampling Sites
Southwestern Wyoming Pesticide Groundwater Sampling Sites
Southwestern Wyoming Pesticide Groundwater Sampling Sites
- Publications
Below are publications associated with this project.
Pesticides in Wyoming Groundwater, 2008-10
Groundwater samples were collected from 296 wells during 1995-2006 as part of a baseline study of pesticides in Wyoming groundwater. In 2009, a previous report summarized the results of the baseline sampling and the statistical evaluation of the occurrence of pesticides in relation to selected natural and anthropogenic (human-related) characteristics. During 2008-10, the U.S. Geological Survey, inAuthorsCheryl A. Eddy-Miller, Timothy T. Bartos, Michelle L. TaylorPesticides in Wyoming's rivers, 2006-10
In 2006, the U.S. Geological Survey completed a study in cooperation with the Wyoming Department of Agriculture to determine the occurrence of pesticides in four major rivers within the Bighorn and North Platte River Basins in Wyoming. Surface-water samples were collected at five sites during three different times of the year and detectable concentrations of pesticides were measured in samples colAuthorsCheryl A. Eddy-MillerOccurrence of Pesticides in Ground Water of Wyoming, 1995-2006
Little existing information was available describing pesticide occurrence in ground water of Wyoming, so the U.S. Geological Survey, in cooperation with the Wyoming Department of Agriculture and the Wyoming Department of Environmental Quality on behalf of the Wyoming Ground-water and Pesticides Strategy Committee, collected ground-water samples twice (during late summer/early fall and spring) fromAuthorsTimothy T. Bartos, Cheryl A. Eddy-Miller, Laura L. HallbergPesticides in Ground Water of Wyoming, 1995-2006
In 1991, members of local, State, and Federal governments, as well as industry and interest groups, formed the Ground-water and Pesticides Strategy Committee (GPSC) to prepare the State of Wyoming Generic Management Plan for Pesticides in Ground Water. Little existing information was available describing pesticide occurrence in ground water; therefore, statewide baseline ground-water sampling wasAuthorsCheryl A. Eddy-Miller, Timothy T. Bartos, Laura L. HallbergPesticides in surface water in the Bighorn River and North Platte River basins, Wyoming, 2006
In 2006, the U.S. Geological Survey (USGS), in cooperation with the Wyoming Department of Agriculture, sampled five surface-water sites in Wyoming-three in the Bighorn River Basin (BRB) and two in the North Platte River Basin (NPRB) (fig. 1). The purpose of the sampling was to describe the occurrence of pesticides in these basins during three different times of the year. This fact sheet presents tAuthorsCheryl A. Eddy-Miller, Gregory K. Boughton, R. E. Woodruff - Partners
Below are partners associated with this project.