Humboldt Bay King Tides Photo Initiative: Dec. 13-15 and Jan. 11-12

Jennifer Kalt, Humboldt Baykeeper Director

The highest tides of the year – known as King Tides – are coming on December 13-15 and January 11-12. Please join our King Tide Photo Initiative to help document rising sea levels around Humboldt Bay!

The highest tide of this winter is predicted to peak at 8.7’ at 9:56 a.m. on Sunday, Dec. 13 at the North Spit tide gauge. The high tides could be even higher depending on rainfall, atmospheric pressure, and wind (see below for a complete list of dates and times).

In the Humboldt Bay area, relative sea level is rising at twice the average rate along the West Coast, because the ground beneath the bay is sinking due to tectonic activity as fast as the sea is rising. King Tides are about a foot higher than typical high tides, providing a glimpse of what to expect as sea level rises. In the year 2030, the monthly high tides will be approximately one foot higher than they are today. 

We need to plan for sea level rise in areas like U.S. Highway 101 just north of Eureka, which is expected to flood once a month by 2030.  

Expanding erosion under the railroad dike next to U.S. Highway 101 at Bracut, between Arcata and Eureka. Photo above taken October 28, 2015 by Nancy Stephenson. Photo below taken January 11, 2020 by Jen Kalt.


By capturing images of these extreme high tides, scientists and coastal planners hope to gain insight into how rising sea levels will impact coastal areas in the future. The King Tides Photo Initiative is a great opportunity for volunteers to contribute to a long-term dataset, while helping inform residents and decision-makers about the need to plan for the coming changes to our natural and built environments.

Baykeeper volunteers have been documenting King Tides since 2011. To get involved, all you need is a camera or a smartphone and submit your photos to


Be very cautious of rising water, eroding shorelines, and flooded roadways.


Recommended locations to observe high tides include: 

  • Halvorsen Park and the F Street boardwalk in Eureka 
  • Eureka Slough behind Target
  • Fisherman’s Statue on Woodley Island
  • Arcata Marsh & Wildlife Sanctuary
  • Mad River Slough Bridge on Highway 255 in Manila
  • Liscom Slough on Jackson Ranch Road in Arcata
  • Fields Landing and King Salmon. 


The tides in these locations vary in both height and peak time. Check your favorite tide tables or NOAA’s tide predictions for various locations. Below are the King Tide predictions at the North Spit:


  • Sun. Dec. 13: 9:52 am
  • Mon. Dec. 14: 10:56 am
  • Tues. Dec. 15: 11:21 am


  • Mon. Jan. 11: 9:30 am
  • Tues. Jan. 12: 10:20 am


Little Lake Industries Cleanup

On October 21, the Arcata City Council approved a federal grant application for funding to clean up dioxin-contaminated soil at the former Little Lake Industries lumber mill on South I Street. This cleanup has been a long time coming. In 2015, a major dioxin hotspot was discovered in bay sediments at the mouth of Butcher’s Slough, which flows through the former mill site, and we have been pressing for a cleanup of the City-owned property ever since. This site is not the only source of dioxins in Butcher’s Slough, but this cleanup is a big step in the right direction. And it may lead to a much-needed dog park, which has been proposed on the site.

Butcher’s Slough, the tidally-influenced lower reach of Jolly Giant Creek, flows through a former lumber mill site at the Arcata Marsh and Wildlife Sanctuary before entering Humboldt Bay.



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