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 Nisqually Delta in the South Sound sub-basin historically contained 2,502 acres of vegetated wetland along a 20 km shoreline. The delta receives flow from a 214,377 square kilometer watershed. These characteristics make this system the 5th largest delta out of 16 systems in Puget Sound.
- Simenstad et al 2011 found that this system had lost 77% of its vegetated tidal wetlands, and 68% of its shoreline length. Of the remaining shoreline, 73% shows some evidence of infrastructure development. In the surrounding uplands, 17% of land is estimated to have greater than 10% impervious surface. Across the watershed, 25% of land is estimated to have greater than 10% impervious surface. Based on these paramters, the site was given a degradation score of 52 out of 100, making it the 5th most degraded delta in Puget Sound. It faces a medium risk of future development locally, and a medium risk of development across the watershed. Approximately 44% of the watershed is currently impounded behind dams.
Restoration Efforts and Issues
- The Nisqually Refuge Restoration and Red Salmon Slough Restoration have largely restored historical tidal flow in the Nisqually Delta.
- While these projects removed river levee, The Nisqually Refuge dike and I-5 causeway constrain how freshwater, fish and sedimentparticles of clay, silt, sand, gravel, or cobble, transported by water, are called sediment. enter the delta.
- The Alder Dam impounds river sedimentparticles of clay, silt, sand, gravel, or cobble, transported by water, are called sediment. from a portion of the Nisqually basin, limiting sedimentparticles of clay, silt, sand, gravel, or cobble, transported by water, are called sediment. that reaches the delta.
- The Nisqually Delta is part of WRIA 11 which is the subject of multiple management efforts. The Delta is a key component of the Nisqually Salmon Recovery Plan. The Nisqually Tribe serves as the Lead Entity Coordinator for WRIA 11.
- The Nisqually Reach Nature Center supports environmental education and citizen science.
- The Nisqually National Wildlife Refuge is managed by the USFWS.
- USGS and Nisqually Indian Tribe have been providing leadership on monitoring the site, with USGS focussed on delta sediment dynamics and vegetation and the Tribe focussed on delta salmon utilization
- USGS Nisqually Delta Restoration] provides a web archive of project site information.
- USFWS, USGS SF Bay Station, USGS CHIPS Team, Nisqually Indian Tribe are collaborating in ongoing monitoring of system wide response to restoration.
- Ellings 2011 provides an early overview of monitoring strategy
- Takekawa & Woo 2013 is a recent proposal for monitoring to ESRP
All Nisqually Delta Content