For the Swinomish people of northwestern Washington, water is life. But this symbiotic relationship between man and nature has been disrupted, and increasingly threatened, by sea-level rise and changes in Northwestern storm and rainfall patterns.
The Tribe has lived within the Skagit River-Delta of Puget Sound for centuries, fishing the region’s brackish waters for food and maintaining their homes along the shoreline while also working to keep them clean and healthy.
The Swinomish homelands and way of life are affected by the combined threat of intense stream and coastal flooding, both of which are associated with sea-level rise and warmer air and sea-surface temperatures. The regional economy is affected as salmon and shellfish populations decline. Increased stress is also placed on important Pacific Northwest agricultural areas, which provide 75 to 95 percent of the U.S. supply of spinach, cabbage, and beet seed.
"Swinomish fishermen have been out there since time immemorial, but climate change brings extra facets," said Jamie Donatuto, an environmental health analyst with the Swinomish Indian Tribal Community.
This year alone, storms destroyed valuable fishing equipment and threatened to cut off the Swinomish people from their traditional seafood diets. These diets, tribal elder Larry Campbell stressed, mean much more than nutrition.
"They're also spiritual foods for us," Campbell said. "We call it feeding our spirits when we eat these foods."
Rising waters also threaten many of the Swinomish's most important archaeological and cultural sites, in addition to flooding their homes. And unlike most coastal residents, the Swinomish cannot pick up and relocate.
"There's no place to go," Donatuto said. "The Reservation boundaries don't move as sea level rises."
The Swinomish needed a way to predict where and when the waters rise so they can warn people and take action. After a destructive, 100-year storm event in 2006, tribal leaders in the United States and Canada reached out to the U.S. Geological Survey (USGS) for help.
For a decade, USGS geologist Eric Grossman has worked with the Swinomish Tribe and others in the Puget Sound region to better understand coastal processes and drivers of change.
“Much attention has been paid to the effects of rising waters across open-coast beaches and islands,” Grossman said, “but less research has been conducted in coastal bays like Puget Sound and the rapidly changing Pacific Northwest coast and climate.”
In its 137 years of surveying and studying the landscape of the United States, the USGS has become adept at modeling the dynamic relationship between land and water that occurs near coasts. With support from the U.S. Environmental Protection Agency, the USGS began developing the Puget Sound Coastal Storm Modeling System (PS-CoSMoS). The model is used to forecast sea-level changes and coastal impacts in real time—up to 48 hours in advance and over the coming decades. The model forecasts where flooding and damage are likely to occur by estimating where storm water levels, which can reach from 2 to 3 feet above predicted tides, can cause waves from 3 to10 feet high to impact the shoreline.
"They look to us for guidance on how to help formulate a coastal climate change adaptation plan," Grossman said.
The models and tools developed by the USGS help decision makers make more informed and resilient investments for communities, infrastructures, and ecosystems. Tribe members can anticipate flooded Reservation roads and stock supplies, move valuable fishing equipment to safe locations, and avoid fishing dangerous waters. The Tribe and its partners can design and implement plans that recover declining salmon populations and address threats to infrastructure, agriculture, and the regional economy.
Donatuto and Campbell are ultimately using the coastal change assessments to evaluate adaptation strategies to enhance Swinomish community health.
"Changes in patterns of storms, sea-level rise, and other natural hazards along our coast are not things that most people think about when they first wake up in the morning," Donatuto said. "The CoSMoS forecasts allow people to visualize what the future holds."
For more information about USGS science in the Pacific Northwest, contact Rich Ferrero, USGS Regional Director for the Northwest Region, at firstname.lastname@example.org.
For more information about CoSMoS, contact Eric Grossman, USGS research geologist and tribal liaison, at email@example.com.
Read more stories about USGS science in action.