'Big One' coupled with rising ocean could leave many in Northwest living in flood zones, study finds
If the once-every-500-year Cascadia Subduction Zone earthquake doesn’t do enough damage to the coastal Northwest on its own, frequent and widespread flooding from rising seas that follows will take care of the rest, new research found.
Oregon, Washington and California are overdue for the recurring seismic event — popularly referred to as “The Big One” — which last occurred in 1700 and could cause Northwest coastlines to lower and retreat by more than 6 feet as land erodes into the sea.
Coupled with rising seas from climate change, many more coastal communities, such as Seaside, Oregon and Aberdeen, Washington, will essentially be on top of newly created floodplains and tidal zones amid rising waters.
The findings from researchers at Virginia Tech, the University of North Carolina, the University of Oregon and scientists at the U.S. Geological Survey were published last week in the Proceedings of the National Academy of Sciences. They found that if The Big One were to occur in 2100, when waters along the Pacific coastline might be three feet higher than today as global ice sheets melt, it’s likely 6.6 feet of Northwest coast would subside into the sea.
https://washingtonstatestandard.com/2025/05/05/big-one-coupled-with-rising-ocean-could-leave-many-in-northwest-living-in-flood-zones-study-finds/