Watersheds & Science


FrenchCreek_19697Northern Chester County is an area of hills and valleys geologically situated at the top of the Piedmont region. It is broadly bounded by the Allegheny Group of the Appalachian Mountains to the west and the New Jersey coastal area to the east—two factors that contribute significantly to the local climate, often experienced as gray winter periods and near-tropical summers.

The natural, cultural, and historical center of this region begins with its rivers.  The major waterways of Pennsylvania’s Piedmont – the Delaware, Schuylkill, and the Susquehanna – and their countless tributaries, as well as numerous other lakes, ponds, and reservoirs are critical to millions of people, plants, and wildlife as sources of drinking water, transportation, and recreation.  The hills and rocky ridges of the Piedmont form the boundaries of its many watersheds; the streams and creeks drain water from the forests, farms, towns and cities into rivers of ever-increasing size.  The Delaware River, into which the Schuylkill River flows at Philadelphia, is 330 miles long and is the longest undammed river in the country east of the Mississippi.

Do you know your watershed address? Use our maps to find out.

The Schuylkill River forms Chester County’s northeast border. The Schuylkill begins in the Appalachian Mountains of Schuylkill County, and flows to the Delaware River in Philadelphia.  It is 128 miles long and is considered a National and State Heritage Area.  It is rich in historical significance and is well-known for beautiful, sweeping countryside.

Five major streams form the watersheds of northern Chester County. The largest of these streams is French Creek. The others include Pickering Creek, Valley Creek, Pigeon Creek, and Stony Run. A series of smaller streams at the very northern end of the county are referred to collectively as “Direct Schuylkill Drainage”.

In all, the watersheds that Green Valleys stewards cover an area of 151 square miles.

These streams provide a major habitat for aquatic and amphibious life and are considered a fly-fisher’s paradise. A cornerstone of the Green Valleys Watershed Association’s mission is to protect this environment, in both its water and landscape forms. The watershed streams within our protection are all afforded Special Protection by the Commonwealth of Pennsylvania—a distinction worth preserving.