This study will provide input to the Environmental Protection Agency as it revises its Multi-Sector General Permit (MSGP) for industrial stormwater. Stormwater that passes through some sort of engineered conveyance, be it a gutter, a pipe, or a concrete canal, is regulated under the Clean Water Act (CWA). Three permit programs under the CWA are used to regulate discharges of stormwater to receiving waters -- one for municipalities, one for construction sites, and one for industrial facilities. Of these, industrial stormwater is particularly challenging to manage because of the wide range of industrial sectors that must be accounted for.