Stormwater runoff in the Arrowhead drainage basin immediately below Arrowhead Country Club during a May 2010 storm event in Rapid City, SD. Runoff from this drainage discharges into Rapid Creek. Stormwater runoff from urbanized lands is known to harm surface-water resources by increasing stream velocities, destroying natural habitat, and increasing pollutant loads in the receiving waters. The City of Rapid City, SD, encourages use of various best-management practices, such as detention ponds, vegetated channels, and disconnected impervious area, for reducing the environmental effects of stormwater pollution. Stormwater runoff data were collected in three drainage basins within Rapid City, SD, during 2008-14. Stormwater runoff was evaluated for concentrations of total suspended solids, chloride, bacteria, nutrients, and metals in selected drainage basins.