Site Description
Terminal 25 (T-25) South is on the southeast bank of the East Waterway at 2917 East Marginal Way South in Seattle, Washington. T-25 South includes approximately 5 acres of upland area and 5 acres of submerged and intertidal areas. The in-water portion of the site contains a derelict pier structure with creosote pilings. On behalf of the Port, the Northwest Seaport Alliance currently leases portions of the upland T-25 South to various tenants who use the area for equipment and material laydown, light industrial activity, and truck parking.
Site History
Prior to the channelization of the Duwamish River in the 1900s, the land occupied by present-day T-25, was part of the Elliott Bay tide flats. During channelization, the flats were filled with various materials including dredged soils. The Port acquired the site in 1913. The site was used for cold storage, logging facilities, and as a sawmill during the early 20th century. The sawmill was removed to allow for lumber storage and automobile staging in the early 1960s. During the 1980s, it was used for cold storage, seafood processing, and shipping operations. Most structures and buildings at the site were demolished in the 1990s.
(Existing conditions at Terminal 25 South site.)
Contamination Issue
Historical activities contaminated the sediment and soil at the site. The primary contaminants of concern are polychlorinated biphenyls, dioxin and furans, and petroleum.
What is the Port’s Role in this Cleanup?
As the property owner, the Port is leading the effort to address contamination at the site. The cleanup will be designed to protect human health and the environment at the Site, as well as to prevent recontamination of the adjacent East Waterway.
Following the cleanup, the Port plans to construct critical fish and wildlife habitat to support recovery of the endangered Southern Resident orca. The restoration will significantly increase habitat critical for Chinook salmon, the primary food source for the orcas. The goal is to restore estuarine wetland functions across the site as well as to restore and create riparian habitat and off-channel rearing and refuge habitat for salmonids and other migratory and resident fish and wildlife in the East Waterway. The project will ultimately re-establish approximately 10 acres of riparian, emergent marsh, mudflat, and subtidal habitat.
Status
The site is currently in the process of being cleaned up under the oversight of the United States Environmental Protection Agency (EPA). The sediment, soil, and ground water investigation were completed in 2024. An engineering evaluation/cost analysis was submitted to the EPA in the winter 2025. The Port anticipates receiving the EPA’s cleanup approval in mid-2026 following a public comment period.
Contact Information
Joy Dunay | Senior Environmental Program Manager | [email protected]
