Evaluation of Large-scale Use of Green Stormwater Infrastructure as a Stormwater Controls Measure

Chester, PA

The Stormwater Authority of the City of Chester (SAC) was founded in January 2016 “to regulate discharges to the Municipal Separate Storm Sewer System (MS4) to protect the City of Chester and Delaware County’s water bodies and groundwater and to safeguard the public health, safety, welfare and the environment.” At the time, the SAC was in the process of developing a community-based partnership (CBP) to plan, design, build, finance, operate, and maintain the retrofitting of impervious surfaces through integrated green stormwater infrastructure (GSI) practices for a planned 30-year period.

Project Scope

  • Research and Analyses
  • Scale up of GSI Program
  • Equity Considerations
  • Water Quality and Ecosystem Health
  • Private and Public Sector Partners
  • Feasibility Assessment
  • Concept Plans

As the CBP was being established, CIS partnered with HDR Engineering, Inc. to perform a Project Evaluation and GSI Feasibility Study. These two tasks were carried out under a grant from the Pennsylvania Infrastructure Investment Authority (PennVEST), which provided funding to advance the development of SAC’s Stormwater Controls Program (Program).

The project team evaluated potential project sites based on their ability to meet the SAC’s program goals:

  • Revitalize the community
  • Create jobs and economic growth
  • Increase property values
  • Improve public health and safety
  • Improve water quality
  • Mitigate surface flooding
  • Provide recreational facilities
  • Create community partnerships
  • Provide public education opportunities
  • Preserve historic landmarks


Based on the initial screening, the project team investigated the feasibility of ten sites, and eight of these sites were selected for concept plan development. The final report included summaries of proposed projects and GSI, calculations for tributary areas managed, conceptual GSI cost estimates, pictures and maps of proposed sites, reviews of required permits and approvals, and suggestions for additional amenity offerings to generate socioeconomic co-benefits.

Following the Project Evaluation and GSI Feasibility Study, SAC entered into a CBP and since 2018 has implemented many of the projects and GSI identified in the concept plans (see program overview for Stormwater Authority of the City of Chester CBP).


Stormwater Authority of Chester