No matter where you are, you're in a watershed. Chester County's land
area consists of portions of 21 watersheds that ultimately drain to the
Delaware Bay or Chesapeake Bay.
A watershed is the area of land (catchment area) that captures rain and
snow, and then stores, filters, seeps or drains this water into a common
water body (marsh, stream, river, or lake). A watershed includes the
network of streams that drains that surface land area, and the
groundwater and aquifers located underground that contribute water to
Watersheds are separated from adjacent ones by a continuous ridgeline
that forms the watershed’s boundary. Watersheds come in all shapes and
sizes and can be broken down into subwatersheds (or subbasins). Each
water body has its own watershed; some are millions of square miles in
size; others are just a few acres.