Description: A Subwatershed represents the area where precipitation naturally drains to a common water feature. Subwatersheds are part of a larger system of drainage areas within our larger watersheds like the Cuyahoga, Rocky, and Chargin Rivers. In turn, those watersheds are a part of a larger "basin". For Cuyahoga County and much of its surrounding area, our subwatersheds and watersheds drain into Lake Erie and the Great Lakes Basin.
Each of the small subwatersheds has information about its "parent" watershed group and associated websites, which provide detailed profiles of conditions and issues in the subwatershed.
One key characteristic of watershed health is the portion of its land area that is "impervious", such as roadway or roofs. For each subwatershed, we've indicated its impervious cover percentage. The Center for Watershed Protection provides guidelines on appropriate practices for watersheds based on their impervious cover. For example, highly urbanized areas (highly impervious) may only benefit from limited practices, such as retrofitting stormwater systems or replacing traditional parking surfaces with "pervious" surfaces. Less urbanized areas (less impervious) might benefit more by preserving headwater drainage and wetlands.
See the layer "Local Subwatersheds, By Percent Imperviousness" and the accompanying report from the Center for Watershed Protection:
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