The Pennsylvania Department of Environmental Protection (DEP) has developed a new geospatial information system (GIS) mapping website to help local governments and other entities pursuing permits for municipal separate storm sewer systems (MS4s) to obtain information for their permit applications more easily.
Municipalities in an urbanized area (as determined by the latest Decennial Census by the U.S. Census Bureau) must obtain National Pollutant Discharge Elimination System permit coverage or a waiver for stormwater discharges from their MS4.
Small MS4s are required to develop and implement DEP-specified pollution reduction plans for most discharges to streams, rivers, lakes, and ponds that have been identified as impaired by the DEP Integrated Water Quality Monitoring and Assessment Report.
The new MS4 requirements GIS website
gives municipalities with regulated small MS4s an interactive, georeferenced map that visually integrates urbanized areas, waterways flowing through and near those areas, and pollutant reduction responsibilities that municipalities may need to address for waterways that are impaired and receive stormwater discharges from their MS4s.
The new MS4 GIS website is a great supplement to the MS4 Requirements Table
of the specific requirements for the MS4 application.