Baykeeper Update

Help Document King Tides in the Bay

Please join us for the 2nd Annual California King Tides Photo Initiative this winter. To participate, grab your camera and take photos around the Bay and local coast during flooding from extreme high tides December 23-24, January 20-22 and February 7-9.

King tides occur when the gravitational pulls of the sun and moon reinforce one another. While they aren't caused by sea level rise due to climate change, these exceptionally high tides provide a preview of the effects of global climate change. King tides allow us to visualize now how more frequent flooding caused by rising sea levels will impact San Francisco Bay’s shore and shoreline communities.

There are cost-effective steps communities can take to reduce damage from rising sea levels. The first step is to identify the most vulnerable areas.

From Baykeeper’s own patrol boat, we’ll take photos of king tide flooding on shorelines around the Bay. California residents are encouraged to take part up and down the state’s coast.

If you’d like to get involved:

  1. Mark your calendar for December 23 -24, January 20 -21, and February 7 – 9.
  2. To find out what time king tides will occur, go to
  3. Take images of areas that are known to flood and erode, and/or where the high water levels can be gauged against sea walls, jetties, bridge supports, dikes, buildings or other coastal infrastructure. If possible, take comparison photos of the same area at low tide or during a normal high tide. Remember to be safe! High tides can cause hazardous waves and flooding, so please keep your distance from the shoreline as you snap your photos.
  4. Load photos to the California King Tides Flickr group. The higher the resolution the better! For additional details, visit the California King Tides “Share Your Pictures” web page.

The California King Tides Photo Initiative was launched in the winter of 2010/2011 by a partnership of state government agencies and nonprofit organizations. Baykeeper participated last year – click here to see some of the dramatic footage captured from the Baykeeper boat during King Tides in February 2011.