Restoration Alternatives for Armored Puget Sound Public Shorelines

In Puget Sound (Washington State), the decline in abundance of numerous marine nearshore species at several trophic levels has prompted regional efforts towards nearshore habitat restoration.  A key driver for these efforts is federal threatened and endangered species listings of several salmonid species including Puget Sound Chinook Salmon.  Much of the nearshore restoration has focused on reducing the negative impacts of hard armoring such as seawalls, and rock revetments in the intertidal zone.  The intensity of shoreline development at the restoration site and at the landscape level often dictates what goals and approaches to nearshore habitat restoration are appropriate and feasible.

 In this presentation, we will describe habitat restoration projects in two separate public shoreline park locations that were armored prior to project implementation.  The two projects provide different alternative approaches and goals for restoration based on site and landscape level opportunities and constraints.  However, both projects appear successful in providing ecological benefits in response to site constraints.  One project, Olympic Sculpture Park, is located in the highly urbanized City of Seattle downtown waterfront. In this extensively modified setting, restoring ecological processes that preceded settlement was not possible, but partial rehabilitation of ecological function benefiting juvenile salmonids and other nearshore species was implemented.  In contrast, Seahurst Park, located approximately 8 miles south of downtown Seattle, is/was heavily armored for park development, but is bordered by undeveloped shoreline and allowed for a more process-based restoration approach linking sediment supply connectivity with natural beach slopes.

 Our presentation will describe the setting and restoration design approaches at these two very different project sites.  In addition, we will present the University of Washington’s post-construction monitoring data for the two sites which provide insights into the biological response to the restoration.  The monitoring data of these sites will be qualitatively compared and contrasted with regards to the degree of functional restoration that can be expected in the two different park settings.