This U.S. Geological Survey data release provides the data and citations for selected tables and figures in “Agriculture-A river runs through it-The connections between agriculture and water quality”. This Circular is based on the National Water-Quality Assessment Project’s study of Agricultural Chemicals: Sources, Behavior, and Transport. This study focused on the connections between agriculture and water quality by examining multiple components of the hydrological system within agricultural areas to improve the understanding of how agricultural chemicals are transported into and through streams and groundwater. These data support the following publication: Capel, P.D., McCarthy, K.A., Coupe, R.H., Grey, K.M.,...