Predicting Sea Level Rise Impacts on Ag Production
This project will investigate sea level rise impacts on saltwater intrusion and explore methodologies to detect and quantify land subsidence and river channel aggradation changes that may impact agricultural viability now and in future climate conditions; this work will inform the Snohomish Conservation District's Snohomish Agricultural Resilience.
The Snohomish Conservation District will lead a collaborative effort with the Snohomish Sustainable Lands Strategy, UW Climate Impacts Group, Cardno, and NOAA to evaluate how climate change, sea level rise, and vertical land movement are likely to affect agricultural systems in the tidally influenced Lower Snohomish and Lower Stillaguamish river floodplains. This information is anticipated to support estuary restoration as an appropriate response to protecting regional agricultural viability under seal level rise by describing the value of a strategic retreat from vulnerable low-lying areas, and encouraging a renewed focus on protecting agricultural lands and irrigation water resources at higher elevations.
The project team will develop and implement a land subsidence, channel aggradation, and saltwater intrusion study coupled with community engagement activities to create a community vision for agricultural resilience in Snohomish County. This project complements and leverages several ongoing agricultural resilience and salmon habitat restoration project development initiatives in the Snohomish and Stillaguamish estuaries and watersheds, including: 1) restoration project development in the Snohomish and Stillaguamish floodplains; 2) flood modeling, groundwater modeling, and creation of several decision support tools to inform agricultural sustainability and resilience planning and land use decision-makers. The information created through this project and the complementary ongoing initiatives are expected to inform development of estuary floodplain salmon habitat and agricultural land management strategies by the Sustainable Lands Strategy. The Grantee will leverage several existing grant awards that fund hydrologic and hydraulic modeling, sea level rise modeling, and development of decision support tools.