When heavy rains returned to California last winter after an extensive drought, some Bay Area cities experienced flooding for the first time in many years. Now, a new study shows that kind of flooding will become chronic in many Bay Area locations in the decades to come.
The Union of Concerned Scientists report provides even more detail on how much climate change will affect specific Bay shoreline cities, and how soon.
As early as 2035, neighborhoods all around the Bay Area–on Bay Farm Island, Alameda, Redwood Shores, Sunnyvale, Alviso, Corte Madera, and Larkspur– would experience flooding 26 times per year or more, and that’s with moderate sea level rise. By 2060, the number of affected neighborhoods grows to include Oakland, Milpitas, Palo Alto, East Palo Alto, and others along the corridor between San Francisco and Silicon Valley. If the sea level rises faster, that frequency of flooding will occur sooner. Read the full report at http://bit.ly/2vacc5j.
The report raises another problem. The Federal Emergency Management Agency’s maps of flood-prone areas are outdated and don’t reflect sea level rise projections. Those maps determine where property owners can and cannot qualify for federally-subsidized flood insurance, and where communities must construct additional flood protection to retain that insurance.
Outdated maps give communities a false sense of security and lead to uninformed development decisions. Just ask those homeowners near Coyote Creek in San Jose who were flooded out a few months ago.
The State of California and its agencies, including the Bay Conservation and Development Commission, should be aggressively reducing risks to people and property from climate impacts – that has been explicit in the State’s climate adaptation strategy since 2009. Pressing FEMA for updated maps should be high on the priority list.
Here’s a report on the UCS study in the San Jose Mercury News, which quotes Save The Bay:
Chronic flooding from rising seas could plague many Bay Area waterfront communities such as East Palo Alto, Alameda and San Mateo within four decades, a nonprofit science group said in a report released Wednesday.
While other studies have predicted inundation of coastal cities, this new study by the Union of Concerned Scientists is the first to put dates on when towns that ring the San Francisco Bay would regularly experience chronic flooding.
Rather than slam shoreline communities with epic floods every few years, rising sea levels threatens to flood streets, yards, parks, homes and businesses in low-lying areas several times a year, the scientists said.
“Cities around the San Francisco Bay will begin to experience more frequent and disruptive flooding in the coming decades and will have to make tough decisions around whether to defend existing homes and businesses or to retreat,” said Erika Spanger-Siegfried, senior analyst in the Climate and Energy Program at UCS and a report author.
Airports and low-income housing in low areas are particularly vulnerable, the study said.
While airports can draw on business income to pay for defenses against rising seas, many poorer neighborhoods are hard pressed to afford bigger seawalls or levees or to move people out of flood-prone areas, said Kristy Dahl, a UCS climate scientist and co-author of the report.
She said the report underscores the need for federal policies to help local communities.
“We shouldn’t have some communities left behind simply because they don’t have the resources of their neighbors,” Dahl said in an Oakland press conference to discuss the study. “A large number of these communities don’t have the resources they truly need to adapt.”
Last year, the federal government announced its first grant to buy and relocate a small town — Isle de Jean Charles, La. — for $48 million after concluding it was not worth trying to save the community in place.
The Union for Concerned Scientists study assessed three scenarios — low, intermediate and high sea-level rise — by the years 2060 and 2100, depending on the pace of emissions and melting rates of polar ice. An interactive series of maps show when inundated communities may reach tipping point, with at least 10 percent of usable land flooded at least 26 times per year.
The study found that:
“Imagine what it would be like to have your driveway and backyard flooded every every other week on average,” Dahl said, “And you can’t let your kids play in the back yard because it’s flooded.”
The “low scenario” assumes a San Francisco Bay water level rise of around 2 feet by 2100, a carbon emissions decline, and global warming limited to less than two degrees Celsius — in line with the primary goal of the Paris Agreement.
The “intermediate scenario” projects a four-foot water level rise and carbon emissions peaking around mid-century and about four feet of sea level rise globally. In the high scenario, emissions rise through the end of the century and ice melts faster, causing 6.5 feet of sea level rise.
The group applauded efforts by cities such as San Francisco and Foster City, which already have begun planning where and how to build seawalls and levees. Other regions — such as the cities of Alameda, Hayward and Oakland and Contra Costa, San Mateo, Alameda and Santa Clara counties — are close behind, identifying potential strategies.
Welcoming the report, David Lewis of the Oakland-based nonprofit Save The Bay said it underscored the need for the Federal Emergency Management Agency to update Bay Area flood maps to reflect new projections. Those flood maps determine where property owners can and cannot qualify for federally-subsidized flood insurance, and where communities must construct additional flood protection to retain that insurance.
He urged the state to press FEMA to update the maps. Congress also must be prodded to provide funding for the updates, he added.
“If maps don’t incorporate projections for sea level rise — and for increased frequency of flooding from extreme storms independent of sea level rise — then communities have a false sense of security, and property values, as well as public and private planning and development decisions, don’t accurately reflect risks,” said Lewis.
“Ask those homeowners near Coyote Creek,” which flooded last winter, he said.
It’s amazing how resilient nature can be when we give it half a chance. Even in the face of massive urbanization, pollution, and climate change, steelhead trout are returning to a Bay Area creek where citizens have spent years restoring habitat … and it’s right behind the backyards I played in as a child.
As you can see in this dramatic home video, 1.5 to 2-foot long steelhead were recently spotted in San Francisquito Creek exhibiting spawning behavior. Though they often face inadequate downstream flows, trash carried by stormwater, and other obstacles, these fish have returned to try to reproduce. It should be an enormous source of pride for local residents who’ve worked to make it a place fish want to swim.
Just a block from where this video was taken is the house my parents lived in when I was born. In dry months, the creek was a place for kids to explore, and occasionally acquire a poison oak rash. In wet years, we would watch warily as the rushing runoff threatened to overflow the banks. In grade school, I biked over this stretch of creek to buy Slurpees from the 7-Eleven. Now Facebook’s Mark Zuckerberg lives across the street.
San Francisquito Creek forms the border between the cities of Palo Alto and East Palo Alto, and divides Santa Clara County from San Mateo County, draining from the hills above Stanford through Portola Valley and Menlo Park, to empty into San Francisco Bay. The creek’s upper reaches are blocked by Searsville Dam, then it passes under two freeways and Caltrain’s tracks before emptying into the Palo Alto Baylands.
That’s where Save The Bay volunteers have been working for over a decade to improve marsh habitat on the edge of the creek channel, restoring native plant vegetation to areas previously choked with weeds. This restoration can improve water quality and provide organic material to the base of the food chain, which then provides nourishment for nursing fish and other wildlife. The steelhead stars of this video passed through the areas we’ve restored on their way to spawn.
Farther upstream, another local organization, Acterra, has been working for years to restore upland vegetation and reduce erosion that would clog the creek with silt. Now both Palo Alto and Menlo Park are working to reduce creek pollution at its source, through trash reduction measures including bans on plastic bags and Styrofoam. And there are ambitious plans to further improve creek habitat and natural flood protection by widening the creek channel and providing areas for storm overflow.
All around the Bay, local creek advocacy groups have adopted similar goals to restore and improve creeks, even redirecting them out of the culverts where they’ve been buried under streets and buildings, to restore their natural surface flow. As too many of us spend more of our lives indoors, looking at a screen, this expansion of “backyard nature” in urban areas provides multiple gifts to people and animals – none greater than the simple opportunity to easily access nature and reconnect with native wildlife.
There is so much more restoration to achieve, but these visible fish underscore how successful Bay restoration can be, and how important it is for residents to volunteer their labor to create more healthy communities.
We all need to help protect and restore the Bay for ourselves and the next generation. Together, we can make a difference. Join tens of thousands of Bay Area residents and declare that you are For The Bay, get a free sticker, and learn more at www.ForTheBay.org.
Meet Melissa King, an MBA student at Stanford, and a first time volunteer with Save The Bay!
How many times have you volunteered with Save The Bay?
This is my first time! For shame. I am a big fan of the founders.
Do you have a favorite site or experience?
I am thrilled to be here in Palo Alto. I used to sail here as a kid before they stopped dredging. I love the changes though I do enjoy sailing too.
How did you get involved with Save The Bay?
Though a group at the Stanford GSB.
What is the best thing about volunteering with Save The Bay?
Helping to preserve, protect and even expand the natural environment in and around our beautiful Bay.
If you could be one Bay plant or animal, what would it be and why?
A porpoise! I want to swim and play like they do and swim just as fast.
Who is your environmental hero?
What is your favorite thing about the San Francisco Bay Area?
The Bay; its beauty and all the benefits it provides us, from cleansing our environment to transport and recreation.
What is one thing you do each day to protect the environment?
I never drive. I no longer own a car. I also recycle.
Last Saturday, I had the great pleasure of spending the morning with Save The Bay at the Palo Alto Baylands. Along with several of my colleagues on the Palo Alto City Council, I was thrilled to get to a closer look at SF Bay on a special canoe trip. It was a beautiful, clear morning to be out on the bay, with hardly even a breeze. We saw plenty of birds, including the endangered California clapper rail, and even made friends with a bat ray. This photo doesn’t begin to describe how exciting it was to paddle next to this elegant ray as it meandered through the muddy slough just a few hundred yards from the golf course.
After our canoe trip, we joined 65 volunteers who were weeding invasive plants to help protect the seedlings that Save The Bay planted this winter. NBC Bay Area brought them out in force. There were plenty of kids and adults on site to get their hands dirty and celebrate Save The Bay’s work.
We were rewarded with a sense of satisfaction and a “County Fair by the Bay,” complete with food truck, fun games for the kids, and folk music. My personal favorite was the shark photo booth, especially after my morning with the bat rays.
On behalf of the residents of Palo Alto, I’d like to thank Save The Bay for the work they’ve done over the past 50 years to ensure that SF Bay – our bay – is a great place to be. Palo Alto has a proud history of bay protection dating back nearly a century, before it was cool to be green! And there’s nothing like a Baylands paddle to drive home just how foresighted that work was, and how critical to our collective future that we all continue to work together to keep saving the bay.
— Sid Espinosa