Watersheds of Metropolitan Washington
This is a Land Use / Land Cover Map depicting
forests, cropland, park land, waters features
and urban and countryside development in
more than 3000 square miles of the
Metropolitan Washington Region as defined
COG membership of the Metropolitan
Washington Council of Governments (COG)
This map was developed through Land Sat
imagery analzyed by RESAC (Regional Earth Science Applications Center)
in conjunction with the COG Department of Environmental
Programs and the National Park Service.
Analysis for this maps covers the 12 major land
use / land cover classifications as defined by
the Chesapeake Bay Program. The nature of
Land Sat imagery is such that detailed visual
images are not possible as they are when
using high resolution satellite imagery or
low-level aerial photography. However, t he 30
meters per pixel resolution of Land Sat
imagery is very useful for high altitude land
cover analysis using spectral analysis
techniques.
Sophisticated digital analysis software has
been used to calculate the land cover data for
this map and has been 'trained' on higher
resolution data to achieve accurate analysis to
the 90th percentile.
Jan 01, 2022
This interactive map shows most of the minor and all of the major watersheds of metropolitan Washington, all of which drain into either the Potomac or Patuxent rivers.
Areas with blue or black hatch marks denote smaller watersheds that also drain into these rivers. The map depicts the smaller subwatersheds nested within the larger watersheds. When you click on a subwatershed, you can click on the triangle arrow at the top of the popup box (“next feature”) to toggle to see the name of the major watershed in which the subwatershed is located, the overall area of the major watershed, and its percent imperviousness. Use the map to identify the watershed in which you live or work.