Lower Duwamish Waterway Construction Season 1 is Complete!

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Lower Duwamish Waterway Construction Season 1 is Complete!

#1222

South Park Neighborhood Association (SPNA)

monthly meetings, ?2nd Tuesday 6-7:30:

Duwamish River Community Hub

8600 14th Ave S

mailing address:

8201 10th Ave. S.

Seattle, WA 98108

---------- Forwarded message ---------
From: LDWG <info@...>
Date: Fri, Mar 7, 2025 at 5:06?PM
Subject: Lower Duwamish Waterway Construction Season 1 is Complete!
To: <spnaseattle@...>

/ / /

Cleanup Construction Activities

All construction is done in Sediment Management Areas (SMAs) 2A, 2B, 3, 4, 6, 8, 11B, and C1. In SMA 9, installation of sheet pile to stabilize the shore was completed in anticipation of dredging adjacent sediments. This concludes construction activities for the first construction season in the upper reach of the Lower Duwamish Waterway. We are now focused on demobilizing construction equipment. Please see the map of cleanup areas linked below.?

During this first season, construction teams removed approximately 14,000 cubic yards of contaminated sediment, filling 222 rail cars. This is about 18% of the upper reach cleanup area.?

For questions or concerns, you can reach our team at info@... or 1-888-561-LDWG (1-888-561-5394). Visit for the most up-to-date information.??

Weekly Environmental and Community Report for the week of February 24

You may view the weekly report and other previous weekly reports by clicking the link below.??

Construction Season 1 Wrap-up Activities

Season 1 in-water cleanup activities ended on February 27, and the last of the above water work was completed on March 5. Demobilization of the construction equipment will occur during the week of March 10. Demobilization will include removing equipment and supplies from the barges. Demobilization activities will take place at the Contractor’s (Pacific Pile and Marine) waterfront property along South Riverside Drive.?

What to Expect in Construction Season 2

During the second season, from October 2025 into February 2026, the Contractor will resume cleanup activities, such as dredging of contaminated sediment and placement of clean material. Detailed schedules will be developed in summer 2025, and updates will be shared with the community as soon as they become available. ?

Cleanup activities during the second season and beyond will be more visible to the community. Construction vessels and equipment will be operating closer to residential areas, parks, and the South Park Bridge.

Placing concrete to finish the SMA 9 bulkhead wall system (sheet pile wall) (Geosyntec Consultants, week of March 3, 2025).

Filling the space between the original and new SMA 9 bulkhead wall system (sheet pile wall) with concrete (Geosyntec Consultants, week of March 3, 2025).?