Skip to main content
U.S. flag

An official website of the United States government

Increasing threat of coastal groundwater hazards from sea-level rise in California

August 17, 2020

Projected sea-level rise will raise coastal water tables, resulting in groundwater hazards that threaten shallow infrastructure and coastal ecosystem resilience. Here we model a range of sea-level rise scenarios to assess the responses of water tables across the diverse topography and climates of the California coast. With 1 m of sea-level rise, areas flooded from below are predicted to expand ~50–130 m inland, and low-lying coastal communities such as those around San Francisco Bay are most at risk. Coastal topography is a controlling factor; long-term rising water tables will intercept low-elevation drainage features, allowing for groundwater discharge that damps the extent of shoaling in ~70% (68.9–82.2%) of California’s coastal water tables. Ignoring these topography-limited responses increases flooded-area forecasts by ~20% and substantially underestimates saltwater intrusion. All scenarios estimate that areas with shallow coastal water tables will shrink as they are inundated by overland flooding or are topographically limited from rising inland. 

Citation Information

Publication Year 2020
Title Increasing threat of coastal groundwater hazards from sea-level rise in California
DOI 10.1038/s41558-020-0874-1
Authors K.M. Befus, Patrick L. Barnard, Daniel J. Hoover, Juliette Finzi Hart, Clifford I. Voss
Publication Type Article
Publication Subtype Journal Article
Series Title Nature Climate Change
Index ID 70212542
Record Source USGS Publications Warehouse
USGS Organization Pacific Coastal and Marine Science Center