Stormwater Management Plans & MS4 Program

Stormwater Management Plans

Watershed-based stormwater management planning is a requirement of Pennsylvania’s Stormwater Management Act (Act 167). The Pennsylvania Department of Environmental Protection oversees the Act 167 program, including designating the watersheds for planning purposes. Through watershed-based planning, municipal stormwater regulations are coordinated so that upstream control requirements in one municipality do not result in downstream flooding in another municipality. The county has completed plans for 10 of its 17 watersheds and is considering completing one countywide plan to complete the remaining watershed plans and update the existing ones. 

Watershed Map and Stormwater Management Plans

• Watershed Map
• East Branch Perkiomen Watershed Stormwater Management Plan
• Lower Merion Drainage Area Stormwater Management Plan I Executive Summary I Appendices
• Neshaminy Creek Watershed Stormwater Management Plan
• Pennypack Creek Watershed Stormwater Management Plan
• Perkiomen Creek Watershed Stormwater Management Plan
• Stony Creek/Saw Mill Run Stormwater Management Plan I Executive Summary I Appendix
• Swamp Creek Watershed Stormwater Management Plan I Executive Summary
• Tookany/Tacony-Frankford Watershed Stormwater Management Plan
• Valley Creek Watershed Stormwater Management Plan
• Wissahickon Creek Watershed Act 167 Plan

MUNICIPAL SEPARATE STORM SEWER SYSTEM (MS4) PROGRAM

Phase II of the NPDES program, often referred to as the MS4 program, requires the county to develop a stormwater program to address stormwater discharges from county facilities. The county department of assets and infrastructure is overseeing this effort with assistance from the planning commission, parks, and other affected departments.

• EPA NPDES MS4 Program Information
• PADEP NPDES MS4 Program Information