Just what IS a watershed? Maryland DNR has some great information on the Chesapeake Bay watershed, which includes the South River watershed.
The South River Watershed is the land area outlined in light blue. All of the water that falls onto this land drains into South River. All water not absorbed by pervious surfaces or slowed and cleaned by rain gardens, rain barrels, marshes, etc, washes contaminants and sediments with it when it drains into South River.
Where are YOU in the watershed?

South River "Snapshot" Information
Maryland DNR's Water Quality Monitoring Stations:
Results from South Riverkeeper's Weekly Operation Clearwater :
Impact of Land Use on the Water Quality of the Rhode and South Rivers by use of GPS and GIS - Spring 2005
by Sumit dutta and Zachary Powell
Student Training in Aquatic Research Program (STAR)
TMDL's for South River
Maryland Department of the Environment's TMDL's of South River
Read The Federation's Response
TMDL What? The Capital 10-14-06 (great explanation of TMDL process and map)
Report: Building Community Watershed Assesment in the South River Watershed Read this report on work done and prepared by Center For Watershed Protection with support from National Fish and Wildlife Federation in cooperation with South River Federation (Phase I of III).
South River Watershed Community Restoration and Action Plan Read Phase III prepared June 2006