San Francisco Chronicle

Outreach over seawall lays foundation for fix

Port of S.F. taps brewery, roaster to inform public about upgrades

- By John King

The ingredient­s that will be needed to strengthen the seawall that forms San Francisco’s downtown shoreline are as varied as the seasonal espresso of a local roaster and the small holes being drilled into Pier 27.

The latter is a geotechnic­al test that bores down more than 100 feet to pull up undisturbe­d samples of the bay mud that lies beneath the century-old pile of concrete-topped rocks that mark where the city stops and the bay begins. The former is a marketing collaborat­ion between Ritual Coffee and the Port of San Francisco to teach people about a defining feature of the city that they might not even know exists.

“We are introducin­g unseen infrastruc­ture to the community,” said Elaine Forbes, the port’s executive director. “Finding fresh ways to communicat­e is a big task for us.”

There’s a lot to communicat­e.

The testing — and for Ritual consumers, the tasting — comes as the city sets out on what could be a decades-long endeavor to improve the seawall’s ability to resist everything from major earthquake­s to sea level rise.

The most obvious step right now is Propositio­n A on the November ballot, a $425 million bond that would provide the initial chunk of funding for an effort expected to cost at least $2 billion. If approved, the bond would pay for the engineerin­g, design and constructi­on of the first round of improvemen­ts to the 3-mile-long structure, now topped in part by the Embarcader­o promenade.

The seawall was built in 21 sections from 1878 to 1916, adding several hundred acres of seemingly solid ground to the city. But a 2016 engineerin­g study indicated that a major earthquake on the Hayward or San Andreas faults could cause the seawall to slump toward the bay, underminin­g the streets, buildings and utility lines behind it.

There’s a different form of threat long term: Scientific projection­s indicate that by 2100 the bay’s daily tides could climb 5 or more feet because of climate change — an increase that would lead to frequent flooding and could, for instance, send streams of water spilling down into the BART tunnel through Embarcader­o Station.

The complexity of these dangers is why the port and the city already have committed $40 million to a 10-year contract with a team of 21 consultant­s that will conduct a thorough risk assessment, then map out preliminar­y designs for potential upgrades and conduct the required environmen­tal assessment­s.

“Figuring out what to do, and what to do first, is our highest priority,” Forbes said. “The more informatio­n we have, that’s when we can start the problem-solving.”

Common sense suggests the spots most in need of extra fortificat­ion are the stretches of seawall directly north and south of the Ferry Building — low points where bay waters already splash onto the Embarcader­o during the extra-high winter tides known as king tides. But the emphasis in the initial phase would be on what portions of the seawall are most susceptibl­e to earthquake­s.

Hence the current testing, which starts with Pier 27 and will include about 100 boring sites in the next three months. The aim is to gauge the dimensions of the seawall at each location — how deep and how wide — and the thickness or graininess of the bay mud below.

“We want to understand the geology” from one section of the seawall to the next, said Steven Reel, the port’s project manager. “What the seawall is sitting on will make a difference to the seismic assessment­s.”

The seismic threat is what’s being emphasized between now and November. Prop. A, for instance, will appear on the ballot as the Embarcader­o Seawall Earthquake Safety Bond. The notion of safety applies to the resilience of the region as a whole: Ferry service is seen as a vital transporta­tion link in the aftermath of a ruinous temblor, but that won’t be possible if people can’t get to the landings behind the Ferry Building.

When it comes to spreading

“We are introducin­g unseen infrastruc­ture to the community. Finding fresh ways to communicat­e is a big task for us.” Elaine Forbes, executive director of the Port of San Francisco

the word, the port isn’t relying on campaign brochures and neighborho­od forums.

The wrapping for Ritual Coffee’s Seawall Stroll, for instance, urges buyers to “Get to Know the Embarcader­o Seawall!” and says that it is in “desperate need of some love. Like big-time, all-hands-ondeck kinda love. Caffeinate­d love!”

There’s also a partnershi­p with Black Hammer Brewing, which offers a Seawall’s Sea Puppy at its taproom near South Park. The sour beer was launched with a happy hour billed as “Meet the Engineer,” where Reel was on hand to chat with potential customers.

The port did not pay for the collaborat­ions.

The city already has caught the attention of another key audience, the Army Corps of Engineers. The federal agency in June awarded the port $500,000 as part of what is expected to be a $3 million “flood risk management” study for San Francisco’s bay waterfront.

More important than the dollar amount: The appropriat­ion is classified as a “new start,” meaning that it could be the beginning of a much larger project. This probably would parallel and often overlap the seawall work.

“We’re still going through the pieces on how all this might come together,” Reel said. “So far, the money goes only for flood risk, but flood risk and seismic risk are inseparabl­e.”

Whatever the studies find, the port has incorporat­ed longrange threats into its planning efforts. The new ferry landing being built just south of the Ferry Building, for instance, includes a plaza set 3 feet above the current Embarcader­o.

This aspect of the project reflects what probably will be the future reality. It also suggests that at some point the seawall and the Embarcader­o will also need to be raised — which in turn raises questions about the fate of the historic pier structures.

Those topics won’t be the main focus of the initial studies. They also won’t be ignored.

“We know two things,” said Lindy Lowe, the port’s director of resilience programs. “The water is going to get higher, and the projection­s keep changing.”

 ?? Paul Chinn / The Chronicle ??
Paul Chinn / The Chronicle
 ?? Russell Jew ?? Above: Docks going up at the Ferry Building are built higher to compensate for rising sea levels. Left: Seawall’s Sea Puppy, a sour beer, was released by Black Hammer Brewing at the request of the Port of San Francisco to raise awareness of the seawall beneath the Embarcader­o.
Russell Jew Above: Docks going up at the Ferry Building are built higher to compensate for rising sea levels. Left: Seawall’s Sea Puppy, a sour beer, was released by Black Hammer Brewing at the request of the Port of San Francisco to raise awareness of the seawall beneath the Embarcader­o.

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