All Hail The King… Tides, That Is

If you’ve been watching the news, you’ve probably heard some mention of King Tides in places like Sausalito, Mill Valley, San Francisco, and Alameda. A King Tide is no farcical aquatic ceremony, but it is one of the highest high tides of the year. A King Tide is a natural phenomenon that occurs near the Summer and Winter solstices, during the new and full moon phases, when the moon, sun, and Earth are aligned. This alignment causes the strongest biannual gravitational force on Earth’s oceans, resulting in these dramatic tidal fluctuations.

Figure 1. Earth’s tides and the contributing gravitational factors
Figure 1. Earth’s tides and the contributing gravitational factors.

King Tides help us to see today what will be the average daily high tides in 2050 and they show us now where flooding will occur as the sea level continues to rise as shown in the photos below. These photos were submitted to the California King Tides Project, which encourages people to take pictures of their communities to document flooding during King Tides.

Photos a-f. Photos submitted to the California King Tides Project of San Francisco Bay Area communities during a King Tide in Winter 2012/2013. (a) The Embarcadero in San Francisco (b) Sidewalk in Alameda (c) HWY 1 underpass in Sausalito (d) Byway in Mill Valley (e) Sharp Park in Pacifica, (f) Rockaway in Pacifica
Photos a-f. Photos submitted to the California King Tides Project of San Francisco Bay Area communities during a King Tide in Winter 2012/2013. (a) The Embarcadero in San Francisco (b) Sidewalk in Alameda (c) HWY 1 underpass in Sausalito (d) Byway in Mill Valley (e) Sharp Park in Pacifica, (f) Rockaway in Pacifica

Tide gauge measurements can tell us about past and present sea levels —  The sea level in San Francisco Bay has risen about 4 inches since the year 2000. Based on these measurements and more precise climate modeling, scientists can now predict with strong confidence that the Bay Area will see an additional 10 inches of sea level rise by 2050. Beyond 2050, scientists expect sea levels to rise much faster than the current rate, partly because of positive feedback loops associated with global ice melt. Even the most conservative estimates suggest sea levels will rise a minimum of 40 inches by 2100 and as much as 16 feet if the global ice continues to melt faster than previously estimated.

So, what does sea level rise mean for the Bay Area and the people who live here?

San Francisco Bay is one of the most urbanized estuaries in the world. The majority of our seven million Bay Area residents live and work within a half mile from the Bay. We’ve filled in over 80% of the wetlands that once ringed the Bay and built our communities right at the edge of a bay that is expanding faster every day. We can look to King Tide events to show us the areas of this urbanized coastline that will be at risk in the near future.

As I mentioned, King Tides already bring higher sea levels into our coastal communities and flood urban infrastructure, reaching highways and roads in several areas throughout our region, including San Francisco, Marin, Alameda, and San Mateo counties. What I find of particular interest in the images above are the clear skies, demonstrating that the streets are flooded from ocean tides, not rainfall. However, add rainfall and tidal action and these “interesting” images can become downright devastating. The water you see on the pavement and in the streets during the King Tides indicate where the sea level was at that moment in those areas and we can expect to see that sea level every day in 2050 or even earlier. Combining those extreme high tides with large storms could result in devastating impacts, as you can see in the last two images.

Transition zones and rising tides

The Bay has expanded and contracted several times throughout history, but early humans hadn’t established permanent structures at the edges so the wetlands and the people that relied on them were able to migrate inland. Ten thousand years ago, sea levels were rising so quickly that every generation of early humans living along the coast or Bay was probably forced to retreat inland. Wetlands historically transitioned from low tidal marsh to upland terrestrial habitat across areas that spanned a mile or more. Today, most of our existing wetlands are squeezed up against urban infrastructure with narrow or no transition zones so these wetlands have nowhere to migrate. Healthy wetlands act as a sponge, slowing down and soaking up large volumes of water, so healthy wetlands help to keep coastal communities safe by buffering the effects of severe storms and flooding. With narrow transition zones and no migration space, our urban coastal tidal wetlands will drown as the sea continues to rise and will no longer provide the services we need unless we plan ahead.

In 1999, over 100 scientists, managers, and urban planners published the Baylands Goals Report, which became the basis for wetland restoration in the Bay Area and identified the need to conserve and restore 100,000 acres of healthy wetland habitat to provide healthy wetland ecosystems in the Bay Area. In October 2015, more than 200 scientists, natural resource managers, and urban planners published an update to the Baylands Goals report to include recommendations based on climate change. The Baylands Goals Science update includes an entire chapter dedicated to identifying types of transition zones and defining their services while emphasizing the need to accelerate restoration of these important areas of transition. For more information on the science update to the Baylands Goals Report, check out our Habitat Restoration Director’s blog, Baylands and Climate Change and to learn more about the general benefits of transition zones, check out my blog, What is Life without Transition?.

The solutions to climate change challenges are complex, but rising to the top of the list of challenges is the issue of big funding needs. Save The Bay is excited to be working on an important measure to invest critical funding in restoration projects. We are working with the Bay Restoration Authority to place a $12 parcel tax on the ballot throughout the nine-county Bay Area which will produce about half a billion dollars for Bay restoration over the next 20 years.

Communities can help to prepare for sea level rise by becoming involved with and supporting tidal wetland conservation and restoration. So it goes – wide, healthy wetlands between the Bay and urban infrastructure help to keep coastal communities safe from sea level rise.

If you fancy taking pictures and want to help document areas at risk for flooding as sea level rise, use this map to plan your shoot times and locations to photograph the high water in your community this King Tide season and submit your photos to the California King Tides Project.

Saving the Bay: From Rescue to Restoration


What’s that stinky creek out there,
Down behind the slum’s back stair,
Sludgy puddle, sad and gray?
Why man, that’s San Francisco Bay!
– “Seventy Miles” by Malvina Reynolds and Pete Seeger, 1965

Take Action Now
Looking out on the majestic beauty of San Francisco Bay in 2015, it’s hard for many younger and newer residents of the Bay Area to believe that just fifty years ago, Malvina Reynolds and Pete Seeger were shocked enough by its condition that they memorialized it in song as a “Sludgy puddle, sad and gray.”

Yet, it’s true – half a century ago, the Bay was choked with raw sewage and industrial pollution, and plans were to fill in 60 percent of its remaining area, leaving only a narrow shipping channel in its place.

Fortunately, in 1961, Save The Bay’s founders set out to rescue the Bay from destruction, and helped give birth to our nation’s grassroots environmental movement. Mobilizing thousands of Bay Area residents into action over the course of the decade, these three remarkable women led landmark victories including a moratorium on Bay fill, the closure of more than 30 shoreline garbage dumps, an end to the release of raw sewage, and establishment of the Bay Conservation and Development Commission to regulate shoreline development and increase public access to the Bay.

For 55 years, Save The Bay has been occupied primarily with successive versions of our founders’ initial mission to protect the Bay from damaging shoreline development. Along with dedicated local groups, we’ve defeated numerous, hugely destructive plans including: the Santa Fe Railroad Company’s Bay fill scheme to build Berkeley three miles out into the water; David Rockefeller’s surreal fantasy of building a new Manhattan in the Bay with fill from chopping off the top of San Bruno mountain; Mobil Oil’s blueprint for massive development on Bair Island; and SFO’s ill-conceived effort to pave the Bay for runway expansions.

Now, with Cargill’s Redwood City Saltworks proposal on the ropes, and plans to develop Newark Area 4 likely to be rejected by BCDC and the San Francisco Bay Regional Water Quality Control Board, these last threats to the largest remaining tracts of unprotected, restorable Bay wetlands may soon be overcome.

The next phase of saving the Bay

The first phase of our organization’s history, focused on rescuing the Bay, is now drawing to a close; the next phase of our history, focused on restoring the Bay to full health, is beginning in earnest; and the scale of our challenges and the importance of our work are as enormous as they have ever been.

While Bay restoration has always been integral to Save The Bay’s mission, only now, after many years’ effort, do we have a real opportunity to achieve it on scale and realize our founders’ ultimate vision.

In 1999, a consortium of estuary scientists published the Baylands Ecosystem Habitat Goals, which established that San Francisco Bay needed 100,000 acres of wetlands to restore and sustain its health. At the time, less than 40,000 acres of Bay wetlands remained, but thanks to the efforts of Save The Bay’s many partners, a similar number of restorable acres had been protected from any further development. Local efforts have managed to restore 5,000 acres of wetlands since then, but the vast majority of protected Bay wetlands are still awaiting restoration.

The biggest challenge has been the lack of sufficient, reliable funding to pursue large scale restoration. With scant annual federal funding – on the order of $5 million per year – and state support limited to one-time injections of bond funds, the price tag of $1.43 billion to restore the acres under protection has been too steep, and efforts to secure additional funding from existing sources have yielded little.

Faced with the quandary of having thousands of acres of restorable wetlands under public ownership without an appropriate source of funds to restore them, Save The Bay moved to change the equation.

Funding Bay restoration on scale

In 2007, we published Greening the Bay, a strategy for financing Bay restoration by establishing a regional special district that would allow the Bay Area to raise the local share of wetlands restoration costs, which could be used to leverage increased state and federal funding to cover the remainder.

That publication and the organizing around it led directly to creation of the San Francisco Bay Restoration Authority, a regional public agency charged with raising the local funds and managing the grants necessary to implement the many restoration projects in the pipeline and begin the long overdue work of restoring the Bay’s wetlands.

Unfortunately, at its very start, the Authority was stalled out by the stark reality of the Great Recession. In the grips of that extraordinary economic downturn, the same Bay Area voters who had consistently and overwhelmingly supported the goal of improving the Bay for both people and wildlife proved unwilling to pay even a small amount in additional taxes to fund the local share of restoration efforts.

Today, the Authority is preparing to propose a small parcel tax to voters in all nine Bay Area counties, to enhance our environment and strengthen our economy at the same time.

  • The June 2016 ballot measure would generate $500 million in new funding for projects to restore thousands of acres of tidal marsh, making the Bay healthier for fish, birds, seals and other threatened marine life. Parcels would be assessed $12 each year for 20 years.
  • The funding would accelerate projects that prevent flooding of residential communities and economic infrastructure, reduce pollution in the Bay, and improve trails for public
  • An April 2015 survey found that a supermajority of Bay Area voters will make an investment to ensure the Bay is clean and healthy. After hearing arguments for and against, 70% would vote in favor of a $12 parcel tax to improve the Bay – more than the 2/3 necessary for passage.

A recent op-ed in the San Jose Mercury News by Save The Bay’s Executive Director, David Lewis, and prominent business leader Andy Ball made the case and the call: Act now to protect San Francisco Bay!

We can make this breakthrough, and restore San Francisco Bay for all the generations to come, but only if Save The Bay’s supporters lead the way, as we have throughout our organization’s history.

We know our supporters are up to the challenge, and in the weeks ahead we’ll be letting you know exactly what you can do to help. Thank you, as always, for all you do to Save The Bay!