County-wide Act 167 Stormwater Management Plan and 2022 Model Ordinance Update
The 90-day period for Pennsylvania Department of Environmental Protection (PADEP) to review the final 2022 County-wide Act 167 Stormwater Management Model Ordinance ended on November 24, 2022. Under the Pennsylvania Stormwater Management Act (PA Act 167), all Chester County municipalities, both MS4 and non-MS4 permittees, are required to adopt stormwater ordinances consistent with the County's Model Ordinance by May 31, 2023.
On August 17, 2022, the Chester County Board of Commissioners adopted Resolution 55-22 to amend the County-wide Act 167 Stormwater Management Plan for Chester County, PA to replace the 2013 model ordinance with the 2022 County-wide Act 167 Stormwater Management Model Ordinance. This updated ordinance incorporates PA DEP's comments from their review of the Model Ordinance to improve consistency with their state-wide 2022 Stormwater Management Model Ordinance.
It is recommended that municipalities adopt the Model Ordinance as a stand-alone ordinance. After the ordinance has been adopted, we ask that an electronic copy, along with the completed Certification of Ordinance Adoption, be submitted to the Chester County Water Resources Authority (CCWRA) at [email protected]. Municipalities do not need to submit their draft updated ordinance to CCWRA or the Chester County Planning Commission (CCPC) prior to adoption.
Model Ordinance Workshops
In May of 2022, the Chester County Water Resources Authority hosted two implementation workshops to assist municipalities with updating their stormwater ordinances. Links to the recordings and PDFs of presentations delivered at both workshops can be found at this page.
County-wide Act 167 Stormwater Management Model Ordinance Documents
The updated County-wide Act 167 Model Ordinance is the culmination of and was significantly shaped by nearly three years of collaboration between Chester County, its municipalities, residents, and other stakeholders. It was designed to meet the needs of Chester County’s municipalities, fulfill the standards set forth in the Pennsylvania Storm Water Management Act (“Act 167”), and comply with the regulatory requirements of PA DEP’s National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) program. The updates incorporated into the Model Ordinance were also designed to comply with the provisions included in PA DEP's 2022 Model Stormwater Management Ordinance.
Links to updated versions of the adopted Model Ordinance and supporting documents can be found below. The following documents were also updated for consistency with the changes to the Model Ordinance: Appendix B, Appendix E, the Matrix of Minimum Standards, Summary of Changes, and Summary of Options. Municipalities should reference these latest documents when updating their ordinance to be consistent with PA DEP’s 2022 Model Ordinance and the County-wide Act 167 Model Stormwater Ordinance.
- County-wide Act 167 Stormwater Management Model Ordinance (Word document)
(Final PADEP reviewed version, Updated 12/1/2022)
- County-wide Act 167 Stormwater Management Model Ordinance with all changes highlighted (Word document) (Final PADEP reviewed version, Updated 12/1/2022)
- Model Ordinance Appendix A: Simplified Approach to Stormwater Management for Small Projects (Word document)
- Model Ordinance Appendix B: Conservation Design and Low Impact Development Site Design (Word document, Updated 6/2/2022)
- Model Ordinance Appendix C (Complete PDF):
- Model Ordinance Appendix D: West Nile Virus Design Guidance (Word document)
- Model Ordinance Appendix E: Stormwater Best Management Practices and Conveyances Operation and Maintenance Sample Agreement (Updated 6/2/2022)
Model Ordinance Implementation Resources
Below are additional resources to assist Municipalities with updating their ordinances to be consistent with the County-wide Model Ordinance.
- Summary of Changes Table (Updated 6/2/2022): The Summary of Changes Table lists all of the substantive changes made to the 2013 model ordinance.
- Matrix of Minimum Mandatory Ordinance Standards (Updated 6/2/2022): The Matrix of Minimal Mandatory Standards outlines the minimum standards municipal ordinances must include to be consistent with the County-wide Model Ordinance. The Municipality may set more restrictive or stringent standards and requirements than those included in the Matrix, but they cannot set less restrictive standards.
- List of Model Ordinance Sections with Options for Modifying Standards and Requirements (Updated 6/2/2022): This resource provides a comprehensive overview of all sections in the Model Ordinance where the Municipality is presented with choices for determining the level and extent of the standards and requirements to be included in their Ordinance.
- Certification of Ordinance Adoption Form (Word document): Upon final adoption of the model ordinance or equivalent minimum mandatory ordinance standards, each municipality must submit this form to Pennsylvania Department of Environmental Protection’s Bureau of Point and Non-Point Source Management and send a copy to the Chester County Water Resources Authority.
- Example Schedule of Fees (Word document): This example schedule of fees has been modified from the Crum Creek Act 167 Model Ordinance. This document is meant only as an example, and can be modified by the municipality to meet their needs. If the municipality chooses to require fees for stormwater site plan reviews and BMP inspections, it is recommended that a fee schedule be adopted independent of the ordinance to allow for fees to be adjusted as needed without having to go through the public hearing process.
- Response to 45 Day Public Review Comments: This document includes responses to the comments received during the 45-day public review and comment period.
- Watershed Plan Advisory Committee (WPAC) Meetings, Communications, and Members and Public and Stakeholder Meetings and Presentations: This document lists all of the Watershed Plan Advisory Committee (WPAC) meetings, all email communications to the municipalities, and all public and stakeholder input meetings.
County-wide Act 167 Plan Resources
The Pennsylvania Department of Environmental Protection approved the “County-wide Act 167 Stormwater Management Plan for Chester County, PA” on July 2, 2013. The State, through Act 167, requires that all Chester County municipalities adopt the updated ordinance requirements included in the Plan amendment.
Please note, the Plan is more than just the model ordinance (Appendix D) and the components of the Plan are comprised of the following, as shown in the bulleted list below.
- "County-wide Act 167 Stormwater Management Plan Addendum to Watersheds, An Integrated Water Resources Plan for Chester County, PA and Its Watersheds"
(Addendum - without Appendices (PDF, 23 MB, 8.5x11, 37 pages, 5 color)
- Chester County Board of Commissioners' Resolution No. 08-13
- Addendum’s Full size 11x17 color figures (PDF, 14.2 MB, 4 pages)
- Appendix A - Watershed Plan Advisory Committee (WPAC) Members, Meetings and Communications (PDF, 32 pages)
- Appendix B - Ordinance/Standards Committee Members and Meetings (PDF, 2 pages)
- Appendix C - Public and Stakeholder Meetings (PDF, 9 pages)
- Appendix D - County-wide Act 167 Stormwater Management Model Ordinance
- Appendix E - Matrix of Minimum Mandatory Standards for Municipal Ordinances (PDF, 27 pages)
- Appendix F - Christina Basin TMDL Implementation Plan (C-TIP) Partnership Members, Meetings, and Communications and Correspondence with PADEP and EPA (PDF, 5 pages)
- Appendix G - Christina Basin MS4 TMDL Plan (Part 1 - MS4 TMDL Strategy) (PDF, 3.3 MB, 8.5x11, 62 pages, 1 color)
- Appendix H - Certification of Ordinance Adoption
Section 706 of the updated Model ordinance requires inspections of BMPs installed after the adoption of this ordinance to be inspected during or immediately after the cessation of a 25-year or greater storm (for inspections conducted by the municipality) or 10-year or greater storm (all other inspections). Municipalities and those with BMP inspection responsibilities should reference NOAA Atlas 14 when assessing when inspections are required. The chart below provides information on average return intervals for Chester County.
NOAA Atlas 14 Precipitation Estimates
Average of seven locations throughout Chester County, PA
Links to subscribe to real-time precipitation data from the seven USGS precipitation gages in the County are below:
- Schuylkill River at Pottstown (North Coventry Township | Pottstown Borough)
- Valley Creek at PA Turnpike Bridge near Valley Forge (Tredyffrin Township)
- Chambers Lake near Wagontown (West Caln Township)
- West Branch Brandywine Creek at Modena (Modena Borough)
- East Branch Brandywine Creek below Downingtown (East Bradford Twp | West Bradford Twp)
- Brandywine Creek at Chadds Ford (Pennsbury Township | Chadds Ford Township)
- East Branch Big Elk Creek at Forestville (Penn Township | Upper Oxford Township)
Additional precipitation data for Chester County can be found at the following links:
- Act 15 Exemption for High Tunnels in Municipal Stormwater Ordinances (PA DEP Fact Sheet)
- 2013 County-wide Stormwater Management Model Ordinance
- Improving Stormwater Management in Chester County
- PA DEP's 2022 Model Stormwater Management Ordinance
- Pennsylvania Stormwater Best Management Practices Manual
- Chester County's Erosion and Sedimentation Control Program