Manchester Stormwater Retrofit Project

This project provides water quality treatment of stormwater for approximately 100 acres of the Manchester community. The project will also provide pedestrian and traffic safety improvements, roadside rain gardens, a stormwater park, and a new outfall at the beach.

The goal of this project is to improve water in Puget Sound for swimming, wading and fishing. Kitsap County studied options for improving Manchester's stormwater system, and this was the top project identified in the Manchester Stormwater Retrofit Plan completed in 2012. Stormwater runoff from the Manchester community flows into the nearshore area at Pomeroy Park and Puget Sound virtually untreated.

Initially, the project was designed to replace an aging and undersized outfall. However, the County recognized a unique opportunity to remove stormwater pollutants harmful for recreation and marine life from a larger drainage area as well as add community amenities. Phase 1 included the construction of a stormwater park at Colchester Drive and Main Street in 2014-15. This park is Kitsap County's first stormwater park, and adds high-capacity water quality treatment. The design process for this Community Commons area included community input to help determine the appearance and function of the new stormwater park.

Phase 2 was completed in 2015. The project included replacement of the outfall at Pomeroy Park and associated piping.

Phase 3 is currently under construction through September 2016 and includes pedestrian and traffic improvements on Main and Madrona, as well as stormwater infrastructure improvements. The entire project adds approximately 1/2 mile of pedestrian walkways for safety.

The Manchester Stormwater Park project was showcased in an article in the May 2016 edition of Stormwater - Journal For Surface Water Quality Professionals. You can find the link under "Additional Information" or click here

The Manchester Stormwater Park project was selected by the America Council of Engineering Companies for an "Honor Award" presented at the 2016 Engineering Excellence Awards Gala, held April 19, 2016. You can find the link under "Additional Information"

Project Benefits

  • Conveyance Asset Upgrade
  • Flood-Control
  • Green Stormwater Solutions
  • Water-Quality Enhancement


Project Cost
Funded By


Contact Information

Project Contact
Education and Outreach