Severn River's 43,500 acre watershed is located within Anne Arundel County in the developed Washington D.C. - Baltimore corridor. The Severn River's 12 miles of navigable water receives most of its freshwater input from Severn Run, although the river has at least 40 smaller tributaries and coves flanking it.
Mattawoman Case Study
Mattawoman Creek, a 30 mile long tributary to the Potomac River, is located within Prince George's and Charles Counties and supports a diverse, high quality aquatic ecosystem. In fact, Mattawoman Creek Watershed (encompassing 94 square miles) is ranked 8th out of the 137 watersheds in Maryland for freshwater stream biodiversity and is one of the most productive spawning areas for anadromous (shad and herring) and a diverse tidal fish community.