Pearl Street Drainage Improvement Project

Image map of Pearl Street project location.
The City will make drainage improvements in west Beacon Hill.

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 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 project involves:

  • Installing a new sewer pipe along Corson Ave S from S Ferdinand to S Dawson streets
  • Building a large underground storage tank to capture sewage and stormwater during large storm events and then slowly release it into the pipes that run under S Dawson St (view underground storage tank)
  • Constructing a small facility building on the south side of the intersection of Corson Ave S and S Dawson St (view facility building design)
  • Expanding existing pipe between S Dawson and S Bennett streets using trenchless technology (i.e. no excavation for pipe installation) and installing a maintenance hole at the S Bennett street end
  • Installing three aboveground electrical cabinets on the north side of S Dawson St

View the map of new sewer and drainage infrastructure to see what is being installed at S Dawson St near Corson Ave S.


This project is located in west Beacon Hill near Maple Elementary School with work occurring on Corson Ave S from S Ferdinand to S Bennett streets, the street end of S Bennett St, and on S Dawson St between Corson Ave S and 12th Ave S. Most of the work will occur on S Dawson St. Visit project area map.

What's happening now?

The installation of the new sewer pipe upgrade on Corson Ave S was completed in March 2021. 

The contractor completed the construction of the underground storage tank and the exterior of the small facility building near the intersection of S Dawson St and Corson Ave S. Remaining work includes painting the interior of the concrete tank and backfilling and compacting of rock and soil around the tank. During this phase of work, residents can expect:

  • Continued closure of S Dawson St between Corson Ave S and 12th Ave S 
  • Construction noise, dirt, dust, and vibrations
  • Parking restrictions in or near the construction area. Residents are asked to follow "no parking" signage and relocate their vehicles outside of the parking area to avoid being towed.
  • Residents may experience temporary, short-term utility service interruptions while the contractor relocates and reconnects services. Impacted residents will be notified prior to this work.

Once construction activities on S Dawson are complete, the contractor will perform final site restoration. The contractor is expected to finalize work and demobilize by summer 2022.

Learn more about what to expect during construction by reviewing the Construction Phase Overview and the Construction Phase Map as well as signup to receive project email updates.

Anticipated impacts

In general, you can expect:

  • Construction noise, dirt, dust, and vibrations
  • Crews typically work 8-hour days Monday through Friday. Evening or weekend work may occasionally be required. When possible, advanced notice will be provided.
  • Increased construction traffic and staging of large equipment in the area
  • Road/lane closures and parking restrictions near the work areas. Please pay attention to onsite signage and park your car in an alternative area, if needed, to avoid being towed.
  • The contractor will coordinate garbage/recycling/compost pick-up and access for mail delivery for homes near construction. The contractor may relocate your garbage/recycling/compost bins, if needed, to facilitate pick-up. In the event of a missed pick-up, please contact the project team.
  • The contractor will work to provide access for USPS and other delivery services, as needed
  • Emergency vehicles will continue to have access to homes, if needed
  • Paving and other restoration work, which may require temporary 24/7 closures, to be performed throughout construction

Community engagement

Our email list will be the primary means of sharing timely information. Please subscribe to the project email list to receive construction updates.

Early 2018 to late 2019

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

Early 2020

  • Finalize project design and prepare for construction
  • Provide project and construction-related updates
  • Pre-construction activities including Puget Sound Energy gas line relocation

Mid 2020

  • Construction began in late June 2020, and it is expected to take about 16-18 months. 
  • For more information about construction phases, please check out the Construction Phase Map.

Early 2022

  • Construction is expected to be complete by summer 2022. Note, schedule is subject to change. Residents will receive additional information via the project email list about the schedule if schedule changes become necessary.

Public Utilities

Andrew Lee, General Manager and CEO
Address: 700 5th Avenue, Suite 4900, Seattle, WA, 98104
Mailing Address: PO Box 34018, Seattle, WA, 98124-5177
Phone: (206) 684-3000

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Seattle Public Utilities (SPU) is comprised of three major direct-service providing utilities: the Water Utility, the Drainage and Wastewater Utility, and the Solid Waste Utility.