The Humboldt Bay area is experiencing the fastest rate of relative sea level rise on the West Coast. That's because tectonic activity is causing the ground beneath the bay is sinking at the same rate the ocean is rising. According to the California Ocean Protection Council's 2018 projections, sea level in the Humboldt Bay area is expected to rise 1 foot by 2030, 2 feet by 2050, and 3 feet by 2060. In late 2021, scientists reported that Antarctica's Thwaites Glacier is likely to collapse within 5 to 10 years, which could result in an additional 2 to 10.8 feet in sea level rise. The primary impacts from sea level rise are increases in flooding and erosion. Sea level rise will expand the area vulnerable to flooding during major storms, as well as in the rare but catastrophic event of a major tsunami. 
The term 100-year flood is used as a standard for planning, insurance, and environmental analysis. People, infrastructure, and property are already located in areas vulnerable to flooding from a 100-year event. Sea level rise will cause more frequent—and more damaging—floods to those already at risk and will increase the size of the coastal floodplain, placing new areas at risk to flooding.


About 3.7 million Americans live within a few feet of high tide and risk being hit by more frequent coastal flooding in coming decades because of the sea level rise caused by global warming, according to new research.


If the pace of the rise accelerates as much as expected, researchers found, coastal flooding at levels that were once exceedingly rare could become an every-few-years occurrence by the middle of this century.


What do Bay Area airports and some big Silicon Valley companies have in common? They sit right on the edge of San Francisco Bay, where sea level rise is expected to have a big impact by the end of the century.

That may seem far in the future, but state agencies are preparing for climate change now by writing new rules for construction along the bay’s shoreline. As you can imagine, developers and environmentalists aren’t exactly seeing eye to eye.

UPDATE: To see some of the best submitted photos, check out our King Tides Photo Album 2021.
If you missed it, there will be another set of King Tides on January 1-3. 
The highest tides of the year (known as King Tides) are coming Saturday & Sunday, December 4 & 5, and all you need to get involved is a smartphone or a camera! 

This year, we are focusing on the old railroad tracks around Humboldt Bay. Built over a century ago when sea level was 18 inches lower than it is today, the railroad hasn't operated in decades. But coal interests are scheming to seize the railroad from the State of California to export coal to Asia via Humboldt Bay. Visit for more info on the growing coalition fighting this terrible proposal.

Photo: Erosion along the rail line near Bracut Industrial Park, Jan. 11, 2020.