Pesticides and their breakdown products in Lake Waxahachie, Texas, and in finished drinking water from the lake

Abstract

Since 1991, the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program has collected pesticide data from streams and aquifers throughout the Nation (Gilliom and others, 1995). However, little published information on pesticides in public drinking water is available. The NAWQA Program usually collects data on the sources of drinking water but not on the finished drinking water. Therefore, the U.S. Environmental Protection Agency (USEPA), in conjunction with the NAWQA Program, has initiated a nationwide pilot project to collect information on concentrations of pesticides and their breakdown products in finished drinking water, in source waters such as reservoirs, and in the basins that contribute water to the reservoirs. The pilot project was designed to collect water samples from finished drinking-water supplies and the associated source water from selected reservoirs that receive runoff from a variety of land uses. Lake Waxahachie, in Ellis County in north-central Texas, was chosen to represent a reservoir receiving water that includes runoff from cotton cropland. This fact sheet presents the results of pesticide sampling of source water from Lake Waxahachie and in finished drinking water from the lake. Analyses are compared to indicate differences in pesticide detections and concentrations between lake water and finished drinking water.