Template:DPU SNO

Nearshore Strategies Data Report

Cereghino et al 2012 completed a soundwide analysis to identify and describe river delta sites in Puget Sounds as part of a nearshore ecosystem restoration strategy (using remote sensing data c. 2000-2006). The following narrative of this delta site was developed to support distribution and use of analysis results:

The Snohomish Delta in the Whidbey sub-basin historically contained 18,706 acres of vegetated wetland along a 95 km shoreline. The delta receives flow from a 465,216 square kilometer watershed. These characteristics make this system the 2nd largest delta out of 16 systems in Puget Sound.

Simenstad et al 2011 found that this system had lost 90% of its vegetated tidal wetlands, and 37% of its shoreline length. Of the remaining shoreline, 87% shows some evidence of infrastructure development. In the surrounding uplands, 55% of land is estimated to have greater than 10% impervious surface. Across the watershed, 32% of land is estimated to have greater than 10% impervious surface. Based on these paramters, the site was given a degradation score of 54 out of 100, making it the 4th most degraded delta in Puget Sound. It faces a medium risk of future development locally, and a low risk of development across the watershed. Approximately 53 percent of the watershed is currently impounded behind dams.