Pennypack Creek Watershed - Act 167 Plan

December 2012

This plan was developed for the Pennypack Creek Watershed in Bucks, Montgomery, and Philadelphia counties, Pennsylvania, to comply with the requirements of the Pennsylvania Stormwater Management Act of 1978, also known as Act 167. The main objective of the plan is to control stormwater runoff on a watershed basis rather than on a site-by-site basis, taking into account how development and land cover in one part of the watershed will affect stormwater runoff in all other parts of the watershed.

The Pennypack Plan was prepared by Temple University’s Center for Sustainable Communities (CSC) with assistance from NTM Engineering, Inc. The plan was funded by the Philadelphia Water Department and prepared in consultation with municipalities located in the watershed, working through a Watershed Plan Advisory Committee (WPAC) comprised of municipal officials and other interested parties. The plan provides uniform technical standards and criteria throughout the watershed for the management of stormwater runoff from new land development and redevelopment sites.

The final plan offers a unique and highly analytical approach to the Act 167 planning process. While we completed all study elements required for an Act 167 study, we expanded the analytical work to include the evaluation of alternative stormwater improvements to determine their effectiveness in reducing runoff and improving water quality. As this watershed is essentially “built-out,” we concentrated much of our research on identifying opportunities for retrofitting existing stormwater facilities and finding locations for new Best Management Practices or BMPs in areas that are not currently served by stormwater facilities. We strongly endorse the use of stormwater BMPs as the preferred means to achieve improved water quality, groundwater recharge and retention, stream bank protection, and volume control. The implementation of these retrofits and new BMPs in conjunction with regulation of new development and redevelopment through new stormwater ordinances will reduce stormwater problems in the Pennypack Creek Watershed.

Plan Approval Documents (pdf) - Added Dec 2012

Main Report (pdf) - Updated Dec 2012

• Appendix A - Model Ordinance (pdf) - Updated Dec 2012
• Appendix B - Hydrologic Model Parameters and Release Rates (zip file)
  This zip file includes the following spreadsheets and GIS files: Subbasin Parameter Speadsheet for the Existing Conditions Hydrologic Model; Reach Parameter Spreadsheet for the Hydrologic Model; Subbasin GIS Shape File; Stream GIS Shape File; Release Rate Summary Spreadsheet
• Appendix C - Recommended Improvements (zip file)
  This zip file includes the following spreadsheets and GIS files: Detention Sites with Estimated Additional Storage, Costs, and Rankings; Infiltration Sites with Estimated Storage, Costs, and Rankings; Riparian Buffer Sites with Estimated Areas, Costs and Rankings; Detention Site GIS Shape File; Infiltration Site GIS Shape File; Riparian Buffer GIS Shape File
• Appendix D - Pennypack Watershed Culverts (zip file)
  This zip file includes the following spreadsheets and GIS files: Culvert Spreadsheet with Capacity and Flood Exceeding Capacity; GIS Shape File for Culverts