DPD has completed a report assessing the ecological state of Seattle’s marine and freshwater shorelines. This study, titled Seattle Shoreline Characterization Report, provides a comprehensive look at the health of Seattle’s shorelines along the Duwamish River, the Ship Canal, Lake Union, Lake Washington, Green Lake, and Puget Sound.

To create this report, DPD collaborated with King County to apply a characterization model to existing spatial GIS data on water quality, land use, vegetative cover, shoreline armoring, and other factors relevant to ecological functions. This process resulted in data quantifying the health of eight ecological processes: sediment delivery, nutrient inputs, toxins, light energy, hydrology, tidal influence, and wave energy.

Compiling the results of each individual process analysis, DPD has produced maps showing the relative health of different shoreline sections and rating these sections, known as “reaches,” into five categories ranging from “least impaired” to “most impaired.” While there is no question that development has substantially impacted Seattle’s shorelines, it is notable that there continue to be relatively healthy reaches along Seattle’s shorelines.

The findings of this report will be a crucial part of DPD’s ongoing update of shoreline regulations. DPD is currently revising its Shoreline Master Program, which establishes goals, policies, and regulations for Seattle’s shorelines and adjacent property, in order to meet a 2010 State Department of Ecology deadline. State guidelines direct local jurisdictions to protect water-dependent businesses, public access to shorelines, and ecological function. The Seattle Shoreline Characterization Report is an important first step in this process because it establishes baseline information on existing ecological conditions that will help to identify potential restoration opportunities and inform shoreline planning efforts.

To view the Seattle Shoreline Characterization Report or learn more about DPD’s Shoreline Master Program update, please visit www.seattle.gov/dpd/planning/SMPUpdate/.