US Army Corps of Engineers
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Comparison table: moderate versus highly urbanized watershedsUrbanization describes the increasing human use of land and water, which often includes increases in impervious surfaces (e.g., concrete), and water and air contamination. Urbanization often increases the potential for flooding, as well as contamination of aquatic ecosystems.


The figure at right shows a summary of water quality characteristics in wetlands within watersheds of moderate and high urbanization (Thom et al. 2001).


Controlling factors that are affected by urbanization:

Contact information

Ronald Thom, Ph.D

Marine Research Operations, PNNL
1529 W. Sequim Bay Rd.
Sequim, WA 98382