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Impaired Waters and TMDLs

Pilot TMDL Applications Using the Impervious Cover Method

This report provides a description of the Impervious Cover (IC) method and tests its feasibility as a Total Maximum Daily Load (TMDL) development tool using watersheds nominated by five New England States. In the report, we describe the IC method and apply it to complete a set of seven TMDL allocations for impaired watersheds throughout New England. EPA Region I has identified the IC method as a potentially useful, innovative TMDL approach for water bodies impaired by stormwater. This work has been conducted by EPA Region I as part of an initiative to select and apply scientifically appropriate and resource efficient methods to complete TMDL allocation projects.

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