Great Lakes Communities and Ecosystems
Water Cycle How the cycle works Added human pressures

WATERSHED BOUNDARY
A watershed is an area in which rain falls and drains into rivers, marshes, and lakes. The boundary between adjacent watersheds is typically along a ridge separating the water flow, unless modified by the underlying geology. Land use within a watershed has a large effect on water quality within a basin.

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Water Cycle diagram

© 2003 Union of Concerned Scientists Riparian ZonesGreat LakeWetlandsGroundwaterForestsSurface and Subsurface RunoffSurface WaterInfiltrationEvaporationWatershed BoundaryTranspirationPrecipitationCondensation