The Puget Sound Coastal Storm Modeling System

The Puget Sound Coastal Storm Modeling System analyzes the potential impacts of sea level rise on nearshore areas of the Puget Sound region. 

An image of the Puget Sound Coastal Storm Modeling System study area. Image courtesy of USGS.
An image of the Puget Sound Coastal Storm Modeling System study area. Image courtesy of USGS.

Predicting coastal impacts

As sea levels continue to rise, flooding poses an increasing risk to people, habitats, and industries throughout Puget Sound. Flooding, though imminent, may not pose an equal threat to all of Puget Sound’s 2600 miles of vulnerable coastline. To address which areas and communities may flood the most, researchers at the United States Geological Survey (USGS) are using ocean modeling techniques to explore potential scenarios that look more than a century into the future. 

The Puget Sound Coastal Storm Modeling System (PS-CoSMoS), to be completed in the year 2020, combines global climate trends with regional tide patterns and water levels to project wave incursions along the Puget Sound coastline. Results so far indicate increasing wave energy on large swaths of Puget Sound shoreline and an increase in extreme flooding frequency. According to the model, just a single foot of sea level rise could create as many floods in five years as might occur in 100 years under current conditions. Considering the projected sea level increase of nearly six feet by the year 2100, studies anticipate that monitoring risk hotspots will only become more essential in coming decades. Modelers hope this information can help to identify who will be in danger when these floods occur and how continually developing areas can plan for such changes in coming decades.

Similar models used along the California Coast

Researchers are using similar models to address urban planning and social equity issues in shoreline flood hazard zones along the California Coast. The USGS has paired the same CoSMoS framework with census data, industrial plots and land-use maps to create the Hazard Exposure Reporting and Analytics (HERA) application. HERA is an interactive web-based platform that can spatially overlay flood risk assessments with demographic, economic, infrastructure, and land cover data. Similar predictive model frameworks are being developed for the Puget Sound Region and will allow Washington to address issues of climate risk equity and continual coastal growth. 

This article was produced as part of the 2018 Salish Sea Ecosystem Conference student writers project. Funding and support was provided by the Environmental Protection Agency's National Estuary Program and the Salish Sea Ecosystem Conference. 


About the Author: 
Jake Lawlor is a graduate student at the College of Science and Engineering at Western Washington University.