In this episode Nancy describes how the health of the “Nation’s River” has significantly improved over the past several decades and how it is doing today. She discusses the continued sources of pollution to the Potomac River, which includes agriculture in the rural part of the watershed and stormwater in the urban areas, particularly the Washington, D.C. metro region. Nancy explains how the Potomac Riverkeeper Network is working to reduce contamination from coal ash ponds, use citizen science to monitor water quality, and grow freshwater mussels to filter water.