Estuarine Restoration – Urban Industrial Context

South Elliott Bay and the Duwamish River estuary, Seattle’s urban shoreline, have been significantly altered since 1900. South Elliott Bay once included nearly 8.2 square miles of estuarine floodplain, including approximately 1450 acres of tide flat and nearly 1200 acres of tidal marsh. The estuarine floodplain portion of the Duwamish River channel was approximately 19 miles long. Today less than two percent of inter-tidal sand/mud flat remains and less than one percent of marsh habitat is present. A straight and deep Duwamish Waterway, approximately 5.3 miles long, has replaced the former shallow river channel and riparian margin.

The Port of Seattle’s principal marine cargo terminals include approximately 1100 acres of publicly-owned shore land and aquatic area, located in the center of the former Duwamish estuary. The port’s cargo facilities serve as an important threshold for commerce in Seattle and the region, shipping more than 20 million tons of cargo yearly, with a value of $35 billion.

In order to serve existing and expanded business needs, ports must constantly maintain and improve marine cargo facilities. In the past decade the port has worked to match marine facility development needs with fish and wildlife habitat restoration actions, integrating active industrial infrastructure with marine and estuarine habitat restoration.

The port has restored approximately 10.5 acres of fish and wildlife habitat, and enhanced approximately 21 acres, in Elliott Bay and the Duwamish Waterway in recent years. Each of the aquatic habitat projects have been implemented as elements of port infrastructure improvements.

The port’s habitat work illustrates that fish and wildlife habitat restoration is compatible with continuing operation of marine industrial/cargo uses. The port has also successfully combined fish and wildlife habitat with public use of shoreline areas. These sites aid in building interest and an active constituency for environmental restoration.