A Case Study of Multiple Benefits: Achieving Greater Conservation Outcomes by Integrating Ecosystem and Socio-Economic Resilience to Climate Change in a Puget Sound River Delta Conservation Project

River deltas in Puget Sound have been dramatically altered by extensive diking and conversion of habitat to agricultural fields and development. This has had significant impacts on estuary-dependant biodiversity and is a primary limiting factor to the recovery of listed fish species such as Chinook salmon. The “re-plumbing” of estuaries has also affected the resilience of both the ecosystem and the associated human community to climate change. Dike systems have constrained the river flows in a few narrow channels, changing the way that freshwater and sediment are delivered to the estuary. These freshwater and sediment processes are central to an estuary’s ability to adapt to climate change impacts such as sea level rise. At the same time, the dike system has constrained flood flows, increasing their energy and reducing the space in which high flows can be absorbed. Dikes protect farmland and the community from moderate floods, but major floods overtop or breach dikes and cause significant socio-economic damage. Local projections of climate change suggest that there will be less snow and more rain during winters in the Skagit River watershed, leading to greater water volumes during major floods. Projections suggest that the 100-year flood for the Skagit may carry as much as 30% more water by 2040 than the 20^th century 100-year event. Such an increase in major flood volumes represents a significant increase in socio-economic risk to the local farming community. Conservation projects that incorporate both ecosystem and socio-economic resilience to climate change can bring together non-traditional partners and result in significant benefits to the ecosystem and reduced vulnerability to the human community. We will describe an acquisition and restoration project that included both conservation and agricultural stakeholders from the beginning, with simultaneous objectives of ecosystem restoration and reduced socio-economic vulnerability. This case study demonstrates a Multiple Benefits approach to conservation that will be an essential tool to achieving greater conservation outcomes in the context of climate change and working lands.