Can Foster City's new massive steel wall keep sea level rise at bay?
Instead, since February, construction workers have been methodically erecting a 2-mile-long wall of thick steel plates that rise from the old earthen levee. Beach Park Boulevard in Foster City looks and feels suburban, a wide roadway lined with single-family homes and small apartments that face San Francisco Bay. Rising Reality A look at the difficulties facing communities bracing for climate change all along San Francisco Bay. Part 1 : Mission Creek  Mission Creek Part 2 : Foster City  Foster City Part 3 : Hayward: July 2  Hayward: July 2 Part 4 : Highway 37: July 16  The city of 32,000 people at the foot of the San Mateo Bridge dates to 1962, when 18 million cubic yards of sand were dumped into the remnants of a tidal marsh along San Francisco Bay. It wouldnt exist except for the levee around the edge that now is being replaced by a stronger and taller one  in part to keep out the higher tides anticipated with sea level rise. The $90 million project began last October and extends 6.2 miles in all. It is being financed by residents who were warned that without a new levee they would be forced to buy expensive flood insurance. Until work is completed in 2023, the joggers and strollers who previously used the trail atop the levee are being steered to the sidewalk along the homes. A bike lane hugs the concrete barricades of the construction zone. Im spending a lot more time in my parks than I did a few months ago, admitted Sanjay Gehani, the mayor, one of many residents deprived of daily strolls with wide views of the bay. But well definitely be getting a better levee. Its a big project with a big payoff.  Whatever the payoff  including a wider levee-top path  the newly fortified wall will serve as a cautionary tale. Dan Stys looks out the window of his mother-in-laws rental home in May as he prepares it for new tenants on Beach Park Boulevard in Foster City. The steel plates that form the backbone of a rebuilt and taller levee can be seen across the way. Carlos Avila Gonzalez / The Chronicle  Foster City is one of several large developments built along the bay in the decades after World War II, when the regions population was exploding and decision-makers had no compunction about pushing as far into the water as engineering technology would allow. Now, these settings face the reality that nature can only be defied for so long. Thats why the residents of the community have little choice but to build an emphatic wall supported by interlocking steel plates. Foster City shows what happens when theres no wiggle room, said David Lewis, executive director of the environmental group Save the Bay. Theyre buying themselves a few decades. We hope.  The conversion of marshes and mud flats along the bay dates to the Gold Rush, when newcomers to San Francisco leveled sand dunes so they could extend the fast-growing city as much as 12 blocks into the bay. Foster City took the casual defiance of nature to a new level. The natural mosaic of rivulets and pickleweed gave way by 1900 to commercial oyster beds and then a dairy farm on swampy grazing land, in the words of one historical account. But the growth of San Francisco to the north and the emergence of Silicon Valley to the south signaled a much more urban future. Wood-framed single-family homes sprout in the planned community Foster City, which was conceived in the early 1960s by T. Jack Foster Jr. Photographed Aug. 12, 1974. Dave Randolph / The Chronicle  Enter T. Jack Foster and his sons, developers who purchased the 2,600-acre dairy farm in 1960, and one year later submitted a plan to San Mateo County to build a new community that could hold 35,000 residents. Construction crews followed not long afterward, eventually hauling in sand from shoals off San Bruno to elevate the huge site 8 feet above sea level. Once known as Brewers Island, a marshy dairy farm was reborn as Foster City, beginning in the early 1960s. This 1974 photograph shows a newly completed housing tract. Dave Randolph / The Chronicle  The citys early development brought such suburban staples as the garden apartments and single-family homes on Ocean Beach Boulevard. Theyve been joined since 2000 by boxy condominiums and glassy office buildings. In 2014 something else was added. A ticking clock  an expensive one. The Federal Emergency Management Agency notified Foster City that new studies showed the existing levee was neither strong enough nor high enough to resist a major storm and the waves it might generate. Unless it was rebuilt, FEMA would designate nearly the entire city as being in a revised floodplain. The city drew up plans for a new levee that would meet FEMAs criteria. But it didnt account for sea level rise projections, which brought a warning from the Bay Conservation and Development Commission, a state agency that must approve any projects along the bay. Large shoreline projects ... must be resilient to a mid-century projection of sea level rise, including risk associated with storms, the agency said in a 2017 letter. The commission cannot approve a project that is not consistent with the policies of the San Francisco Bay Plan.  The past San Mateo County, 1894 0 1 San Francisco Bay MILE Mariners Point Seal Slough Belmont Slough (FOSTER CITY) SAN MATEO REDWOOD SHORES The present Foster City, after 1962 San Mateo Bridge San Francisco Bay Seal Point Park Mariners Point Golf course Seal Slough Belmont Slough FOSTER CITY FOSTER CITY BLVD. 101 92 SAN MATEO Redwood Shores Lagoon REDWOOD SHORES BELMONT The future with 48-inch sea level rise New levee plan Concrete flood wall Hybrid sheet pile Earthen levee (no wall) Mariners Point Depth of flooding 1-2 feet 12 feet FOSTER CITY Leo J. Ryan Park Shorebird Park Edgewater Park Sea Cloud Park SAN MATEO Redwood Shores Lagoon BELMONT John Blanchard/The Chronicle | GIS data from ART Bay Shoreline Flood Explorer and San Francisco Estuary Institute  Taking the hint, Foster City added several feet to the levees design, lifting its peak above projected sea levels for the bay through at least 2050 and satisfying the commissions rules. The steel is thick enough to resist not only earthquakes and strong storms  and the pressure of the 100,000 cubic yards of new soil that will be packed in behind the interlocked plates  but to support an addition when and if theres a need to go higher. When the project went to local voters in 2018, capturing 80% of the vote, the chief selling point wasnt the virtue of a proactive response to climate change. Instead, city leaders emphasized that while homeowners would need to pay an average of $272 annually to finance the bond, flood insurance rates would be at least $2,000 a year. One year later, the bay commission signed off on the final design. Loading... The current levee is 5 to 6 feet lower along the open bay   than the upgraded levee that will stretch 6.2 miles, from Redwood City under the San Mateo Bridge to San Mateo, with concrete and earthen stretches as well as the steel-reinforced portions. The top 3 feet of steel will be visible from inland   and the steel will oxidize as the sheets age. The project has benefits beyond flood protection, officials say. Where the original earthen levee had boulders facing the water and spongy ice plant facing homes, the upgraded version will be landscaped with a variety of native plants to soften the view from within. The new levee will be 18 feet wide, almost twice the width of its predecessor. The original path will be replaced by separate lanes for pedestrians and bicyclists. Another plus: Foster Citys inland channels of water  echoes of the slough that threaded through the long-gone marsh  will be connected to the bay so water can circulate more naturally. You all took the bull by the horns, City Manager Peter Pirnejad told residents who tuned into an online town hall in late January, complimenting them on their 2018 vote. This is a great opportunity to brag to your neighbors a bit. Were the first west bay city to address sea level rise.  Most people who live on or near Beach Park Boulevard seem resigned, not boastful. Installing steel plates that are part of the rebuilt, taller levee along Beach Park Boulevard in Foster City. Carlos Avila Gonzalez / The Chronicle  I knew it was coming, but I was surprised at first by how tall it was, said James Wagner, who moved into his small house facing the levee 36 years ago. Its quite a change.  At the same time, Its smart to be thinking ahead, Wagner said. Foster City is being proactive. The Army Corps of Engineers didnt leave much choice.  Sue Spiekerman, a 24-year resident who would walk her dog each day atop the levee, also has mixed feelings. I definitely dont like losing access to the levee trail for two years, she said. But if its necessary in order to save our housing, it makes sense to do it now.  Pirnejad conceded as much when leading visitors along the fenced-off levee where machines use vibration pressure to push the steel sheets into the soil. Its not like the city chose to be the front-runner, Pirnejad said. This was forced on us.  When Foster City officials appeared before the bay commission in November 2019 to present their final design, then-Mayor Sam Hindi called his city the canary in the coal mine because of the need to fortify a 20th century levee against 21st century realities. That description is not far off, at least with regard to several projects imposed on the shoreline after World War II. When those people were building those places, they werent thinking about climate change, said Jessica Fain, the planning director for the bay commission. We all do what looks rational at the time and then ... fast-forward to today. Ten miles north of Foster City, San Francisco International Airport is in the early planning stages to build a levee with 7.6 miles of concrete and steel walls that will climb at least 13 feet above todays tides. The dimensions are large enough to withstand 36 inches of sea level rise   and the waves that would accompany a 100-year storm. The airport doesnt expect to begin construction before 2025, and the estimated budget is $590 million. In northern Marin County, meanwhile, the U.S. Army Corps of Engineers and the California State Coastal Conservancy are installing a levee to protect Bel Marin Keys  a 1960s vision of Venice-by-the-bay where artificial lagoons are lined by 700 or so homes, far short of the 5,000 that were planned. The tract sits amid scruffy land that has subsided several feet since farmers turned marshes into private fields by erecting a levee to the east in the early 1900s. Those fields are part of ambitious wetlands restoration east of Novato that the Army Corps and the conservancy have been working on for more than a decade. The final phase will remove the old levee to allow 1,900 acres to revert to nature  but the barrier ringing Bel Marin Keys must be completed first. If we were to breach the levee at the bay currently, then Bel Marin Keys would be in trouble, explained Jeff Melby, project manager for the conservancy. If the region could turn back the clock, Foster City might not exist. The runways of SFO might not reach into the bay. Bel Marin Keys might not be a canal-sliced cul-de-sac. But for now and generations to come, their presence is a reality that must be defended. It is hard to imagine the economic disruption or political firestorms that would be caused by proposing to displace entire communities or one of the nations largest airports. For more than a century, too many Bay Area power brokers saw the bays mud flats and marshes as voids to be filled. They had no interest in the ecological value of natural habitats. No idea that sea level rise might cloud the horizon. Which means that places like Foster City have little option but to build higher walls. Ones cloaked by shrubs and trails, perhaps, but defensive barriers all the same. Its not that we cant combat nature with engineering. We can, said David Lewis of Save the Bay. But its a high cost. And with climate change, that cost will grow exponentially.