Agricultural Pesticide Use Estimates for the USGS National Water Quality Network, 1992-2014: Version 2

The National Water Quality Network (NWQN) for Rivers and Streams includes 113 surface-water river and stream sites monitored by the U.S. Geological Survey (USGS) National Water Quality Program (NWQP). The NWQN represents the consolidation of four historical national networks: the USGS National Water-Quality Assessment (NAWQA) Project, the USGS National Stream Quality Accounting Network (NASQAN), the National Monitoring Network (NMN), and the Hydrologic Benchmark Network (HBN). The NWQN includes 22 large river coastal sites, 41 large river inland sites, 30 wadeable stream reference sites, 10 wadeable stream urban sites, and 10 wadeable stream agricultural sites. In addition to the 113 NWQN sites, 3 large inland river monitoring sites from the USGS Cooperative Matching Funds program are also included in the NWQN to be consistent with previous USGS studies of nutrient transport in the Mississippi-Atchafalaya River Basin. This data release provides estimated agricultural pesticide use for 83 NWQN watersheds for 116 pesticide compounds from 1992-2014. Pesticide use was not estimated for the 30 wadeable stream reference sites, or for 3 large river coastal sites (07381590, "Wax Lake Outlet at Calumet, LA3"; 07381600, "Lower Atchafalaya River at Morgan City, LA2"; or 15565477, "Yukon River at Pilot Station, AK"). Use was not estimated for reference sites because pesticides are not monitored at reference water-quality sampling sites. Pesticide use data are not available for Alaska and thus no data is available for the Yukon River site. The other two coastal sites (07381590 and 07381600) where use was not estimated are outflow distributaries into the Gulf of Mexico. This data release provides use estimates for the same pesticide parent compounds sampled in water and analyzed by USGS, National Water Quality Laboratory (NWQL), Schedule 2437: http://wwwnwql.cr.usgs.gov/USGS/catalog/index.cfm. Pesticide use data are not available for degradate compounds or for compounds not used in agricultural applications.