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Pollutant Reduction Plan Instructions (PDF)

TMDL Plan Instructions (PDF)

DEP has prepared an MS4 Requirements Table to assist MS4s with understanding their obligations regarding impaired waters during the 2018 MS4 permit term. The Table consists of two parts – one for Municipal MS4s (PDF) and one for Non-Municipal MS4s (PDF). See also the MS4 Requirements Table Instructions (PDF) for understanding and using the Table and for methods to provide comments. This Table only applies to the 2018 MS4 permit term.

DEP also developed a supplement to the MS4 Requirements Table which is titled Pollutant Aggregation Suggestions for MS4 Requirements Table (PDF) (the Aggregation Table). The Aggregation Table helps permittees interpret the content of the MS4 Requirements Table by grouping the impaired surface waters into separate watersheds. See the Pollutant Aggregation Suggestions for MS4 Requirements Table Instructions (PDF) and FAQ for further explanation.

DEP’s web-based GIS application provides a visual representation of the information contained in the MS4 Requirements Table and the Aggregation Table.


PRP Development Process Summary (PDF): This is a one-page step-by-step suggested approach for developing Pollutant Reduction Plans.

Simplified Method Narrative (Word): This paper describes methods that can be used to calculate existing pollutant load and the load reductions from BMPs.

Statewide MS4 Land Cover Estimates (PDF): This document contains percent impervious and pervious cover, both inside and outside of urbanized areas, for each municipality with an MS4 in PA, which may be used to develop pollutant loading estimates for PRPs and TMDL Plans.

PA Urbanized Area Population Table (PDF)

Information on TMDLs can be found on the EPA TMDL website and also by using the DEP TMDL Tool.

BMP Selection & Crediting

DEP Pennsylvania Stormwater Best Management Practices Manual (363-0300-002)

BMP Effectiveness Values Table (3800-PM-BCW0100m): This table lists the pollutant removal efficiencies for various BMPs.

Stream Restoration Crediting Training: This training provides an overview of the documentation that DEP expects to see when stream restoration projects are submitted for review.

Considerations of Stream Restoration Projects (PDF): This document lists the project siting and technique criteria that must be met in order for a stream restoration project to be eligible for MS4 pollutant load reduction credit.

Stream Restoration Crediting Checklists: These checklists were developed to streamline the review process for stream restoration projects. Permittees are encouraged to review the checklists and become familiar with the level of documentation that DEP expects to see when stream restoration projects are submitted for crediting review.

Expert Panel Reports