Pearl Street Drainage Improvement

Project Description

Reducing stormwater flooding and backups in your neighborhood
Seattle Public Utilities is working on a capital improvement project to upgrade the combined sewer infrastructure in Seattle’s west Beacon Hill neighborhood.
The goal of the Pearl Street Drainage Improvement Project is to reduce storm-related sewer backups and flooding in the area, which will help protect public health and the environment as well as improve service reliability.
This improvement project will involve:

  • Installing a new sewer pipe along Corson Ave S from S Ferdinand to S Bennett streets
  • Building an underground storage tank to capture sewage and stormwater during large storm events and then slowly release it into the pipes along S. Dawson Street
  • Constructing a small facility building on the south side of the intersection of Corson Avenue S. and S. Dawson Street
  • Installing aboveground electrical cabinets on the north side of S. Dawson Street 


This project is located in west Beacon Hill with work occurring Corson Ave S from S Ferdinand to S Bennett streets, the street end of S Bennet St, and with most of the work taking place on S Dawson St between Corson Ave S and 12th Ave S.

What's Happening Now?

The Project Team completed design and is preparing for construction to start in mid-2020. 
SPU is reaching out to nearby residents to share project updates and potential construction impacts prior to construction. In the meantime, please review the Project Fact Sheet for more information about the project.

Community Benefits

The Pearl Street Drainage Improvements project aims to reduce storm-related sewer backups and flooding.

Anticipated Impacts

You can expect:

  • Construction noise, dirt, dust, and vibrations
  • Increased construction traffic and staging of large equipment in the area
  • Lane closures and parking restrictions along Corson Avenue S. for sewer pipe installation during the summer
  • 24/7 full road closure and no parking on S. Dawson Street between Corson and 12th avenues for tank installation and pipe work
  • Short-term driveway access and street parking restrictions on S. Bennett Street
  • Work will typically occur during weekday, daytime hours, but some night and weekend work may be required
  • Temporary, short-term service interruptions to connect to new services. Impacted residents will be notified prior to this work.
  • Site restoration, which may involve 24/7 road closures for repaving work

Community Engagement

If you're interested in learning more and finding out about upcoming community engagement events, please sign up to receive project email updates.


Early 2018 to Late 2019

Project team working on design and permitting
Shared updates with nearby residents

Early to Mid-2020

  • Finalize project design and prepare for construction
  • Provide project and construction-related updates


  • Construction scheduled to begin. Once started, work is expected to take about 16-18 months.

Late 2021

  • Project Completion

Note: permitting, weather, and other factors may impact the start date and duration.