During the period May, 1979-May 1981, nine water quality monitoring stations were operated in small catchments in the Occoquan Watershed of Northern Virginia. The study sites incorporated different land uses (pastureland, corn croplands, suburban development, and forest) as well as contrasting management approaches (heavy vs. light grazing, no-till vs. minimum-till cropping, detention ponds). Water samples were routinely analyzed for total suspended solids, ammonia nitrogen, total Kjeldahl nitrogen, oxidized nitrogen, ortho-phosphorus, total soluble phosphorus, and total phosphorus. Meteorological records were also kept during the study period, and collections of dryfall and precipitation were routinely analyzed. Measurements of atmospheric pollutant loadings indicated the greater proportion to be generally from wetfall.