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Apr
22

M Street Trunk rehabilitation

The M Street Trunk Rehabilitation Project will repair about 2.6 miles of deteriorated sewer pipes in the City of Auburn.

Project description 

The M Street Trunk Rehabilitation Project will repair approximately 2.6 miles of severely deteriorated 18, 24, 30, and 36-inch-diameter reinforced concrete pipe that has more than 100 side sewer connections to nearby properties. The project will also rehabilitate 45 precast maintenance holes.

Active construction is anticipated to occur during the summer window (May to October) of 2025 to 2027 when the wastewater flow is lower.

Project area displaying 5 zones (work areas) and timeframe: Zone 36 (2026-2027), Zone 30 (2025), Zone 30 (2026), Zone 24 (2025) and Zone 18 (2025) 

The M Street Trunk pipe serves a densely populated area with many schools, homes, and businesses in the City of Auburn. During construction for the project, there will be impacts to the travelling public including detours, temporary lane closures, and bus stop impacts. Additional impacts may include on-street parking restrictions, and noise and odors from the diversion pumps. This project may include overnight work. We will share more details as plans develop and will keep the community informed.

Project update

April 2025

Utility investigation work starts April 14th

Starting as early as Monday, April 14 crews working for King County Wastewater Treatment Division will begin digging small holes using vacuum trucks to verify underground utility locations around the M Street Trunk Line in the City of Auburn. Crews expect to complete this work in about a week. Read our latest update to learn more.

Construction starting Summer 2025

We are excited to announce that construction for the M Street Trunk Rehabilitation Project anticipated to start in the summer of 2025. The construction schedule is organized in zones based on the different pipe diameters along the M Street Trunk. Read our latest update to learn more.

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Project location

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