Distribution and Occurrence of Atrazine in an Agricultural Karst Watershed and a Community Supply Reservoir
Institution
Western Kentucky University
Faculty Advisor/ Mentor
Ritchie Taylor
Abstract
The Center for Water Resource Studies, a program of distinction at Western Kentucky University, operates the Technical Assistance Center for Water Quality (TACWQ). Funded by the Small Systems Program of the U.S. EPA's Drinking Water Branch, the TACWQ works to improve source water for small rural water systems. As part of the source water protection program within the Center, water sampling was initiated in 2001 to assess elevated levels of atrazine, a herbicide used for weed control, in Spa Lake and the adjoining karst watershed. This watershed was identified as a priority by the Kentucky Pesticide Workgroup due to atrazine concentrations above the Maximum Contaminant Level (MCL), 3.0 µg/L, in treated drinking water supplied by Spa Lake. Water samples collected since 1999 by Novartis, the company that produces atrazine, and TACWQ indicated that atrazine was persistent year round in Spa Lake, with seasonal variations correlated to the atrazine application season. Weekly monitoring of finished drinking water from the Lewisburg water treatment plant indicated that the herbicide was present in concentrations above the MCL for extended periods of time after the application season. Land use analysis with ARCGIS and stream monitoring indicated that the primary source of atrazine was from applications related to corn production. By understanding the occurrence and distribution of atrazine in the Spa Lake watershed, effective Best Management Practices can be imitated to protect source water.
Distribution and Occurrence of Atrazine in an Agricultural Karst Watershed and a Community Supply Reservoir
The Center for Water Resource Studies, a program of distinction at Western Kentucky University, operates the Technical Assistance Center for Water Quality (TACWQ). Funded by the Small Systems Program of the U.S. EPA's Drinking Water Branch, the TACWQ works to improve source water for small rural water systems. As part of the source water protection program within the Center, water sampling was initiated in 2001 to assess elevated levels of atrazine, a herbicide used for weed control, in Spa Lake and the adjoining karst watershed. This watershed was identified as a priority by the Kentucky Pesticide Workgroup due to atrazine concentrations above the Maximum Contaminant Level (MCL), 3.0 µg/L, in treated drinking water supplied by Spa Lake. Water samples collected since 1999 by Novartis, the company that produces atrazine, and TACWQ indicated that atrazine was persistent year round in Spa Lake, with seasonal variations correlated to the atrazine application season. Weekly monitoring of finished drinking water from the Lewisburg water treatment plant indicated that the herbicide was present in concentrations above the MCL for extended periods of time after the application season. Land use analysis with ARCGIS and stream monitoring indicated that the primary source of atrazine was from applications related to corn production. By understanding the occurrence and distribution of atrazine in the Spa Lake watershed, effective Best Management Practices can be imitated to protect source water.