Sea Level Rise

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 to sink at the same rate that the ocean is rising. According to the California Ocean Protection Council's 2024 Science & Policy Update, sea level in the Humboldt Bay area is expected to rise approximately 1.5-2 feet above 2000 levels by 2060 and 3.9-5.5 feet by 2100. 
The primary impacts from sea level rise are increases in flooding, erosion, and rising groundwater. Sea level rise will expand areas 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. But these extreme storms are happening with increasing frequency, in part due to rising seas. 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. To view sea level rise scenarios for the Humboldt Bay area, visit NOAA's 2022 Sea Level Rise Viewer and go to the local scenario for the North Spit. 
NEW! Now you check out our interactive map of two sea level rise scenarios for the Humboldt Bay Area! Featured are scenarios showing 1- and 2-meters above Year 2000 water levels. For many years, these have been static maps with no simple way for the public to examine points of interest. Now, people wondering if their neighborhood is at risk can zoom in on locations and see street names, etc. 

 

Record tides that flooded King Salmon on Thursday continued to swell on Friday morning, inundating local businesses, yards and even homes — many of which had never been flooded before. Friday morning’s tide provisionally broke the National Weather Service’s all-time record for the region, and storms and southerly wind may result in an even higher tide on Saturday.
Longtime residents, including Greg Stephens, who has operated a shop for his property management business on King Salmon Ave. for more than a decade, said that they had never seen flooding as severe as Friday morning’s.

The highest King Tides of the year arrived in Humboldt County this week, offering both a spectacle and a warning.
Unlike waves or swell, which are wind-driven, tides are the daily rise and fall of the ocean, created by the gravitational pull of the moon and sun. They become “King” tides when the sun, moon, and Earth align as the moon reaches its closest point to Earth. This amplifies gravitational pull, creating extra-high high tides and extra-low low tides.

In a special meeting Thursday morning, the Humboldt Bay Municipal Water District Board of Directors voted to approve an emergency pipeline relocation on the Samoa Peninsula. The project will relocate a stretch of pipeline that feeds county parkland and the U.S. Coast Guard Station Humboldt Bay.
That stretch of pipeline had been found to be damaged by recent high tides and is currently at risk of being undermined by king tides predicted to exceed 9 feet in early December.

King Tides are here! Some very high tides are predicted on Nov. 6 & 7, although the highest tides of the year are expected in December & January. Last year, we released a special EcoNews Report series focused on communities at risk from sea level rise featuring interviews local experts and residents in the Humboldt Bay Area.
This year, we are unveiling StoryMaps with photos and maps to visually explore each episode to help us better understand some of the challenges ahead for our most vulnerable communities.
Episode 1: Is Humboldt Bay the Canary in the Coal Mine for Sea Level Rise? features Marnie Atkins, Jerry Rohde, Troy Nicolini, Adam Canter, and Nate Faith (left).

Humboldt Bay in Northern California is experiencing the fastest rate of relative sea-level rise on the entire West Coast of the United States. Already, the streets and yards in King Salmon, a former fishing village 100 miles south of the Oregon border, regularly flood during particularly high tides. It has made preparing for and adapting to sea-level rise (SLR) a matter of local urgency. And there’s no shortage of agencies and institutions working on it.
In fact, when two California Sea Grant-funded researchers recently listed every entity involved in SLR planning in Humboldt Bay, they counted over 30, including two cities — Arcata and Eureka — a regional harbor district, a county, fifteen federal and state agencies, three Indigenous Tribes as well as various academic, conservation and business groups.

More Articles …

  1. Land Is Sinking Fast Along Parts of the Coast, Worsening the Effects of Sea Level Rise
  2. EcoNews Report: Rising Seas and the Future of Humboldt Bay
  3. Choose your own sea-level rise adventure
  4. Hearing from the Californians on the Front Lines of Climate Change

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