Flooding Study Results Require Action

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 The Federal Emergency Management Agency’s maps of flood-prone areas are outdated and don’t reflect sea level rise projections.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Outdated maps give communities a false sense of security and lead to uninformed development decisions.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:

A Feb. 21 photo from a San Jose city worker shows flooding at 1742 Rock Springs Drive. (City of San Jose)
A Feb. 21 photo from a San Jose city worker shows flooding at 1742 Rock Springs Drive. (City of San Jose)

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:

  • By 2060, in the high sea level rise scenario, parts of many Bay Area communities would face flooding 26 times or more per year, or every other week. Communities with affected neighborhoods include Alameda, Oakland, Palo Alto, East Palo Alto, San Mateo, Burlingame, San Francisco, Corte Madera and Larkspur.
  • By 2100, in the intermediate sea level rise scenario, chronic flooding would affect public infrastructure such as San Francisco International Airport, Oakland International Airport, San Quentin State Prison, Moffett Federal Airfield and the Bay Bridge.
  • By 2100, in the intermediate sea level rise scenario, two Bay Area communities would see more than 10 percent of their land chronically flooded: Alameda and San Mateo.
  • By 2100, in the high sea level rise scenario, more than half of Alameda, about 11 percent of South San Francisco and about 14 percent of Oakland’s land area would be chronically flooded.

“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.


This article was originally published in The Mercury News by Lisa Kreiger and Denis Cuff on 7/12/2017. 

The Case for Swift Action on Wetland Restoration

The Intergovernmental Panel on Climate Change recently released its fifth Climate Change Assessment Report. The report says restoring shoreline areas and taking other ecosystem-based adaptation steps can help coastal communities prepare for climate change, and also provide mitigation benefits. See our previous blog on the subject.

marsh_small

We need to act quickly because the effects of climate change are already being felt, as detailed in a recently released National Climate Assessment by the federal government.

Though wetland restoration will not be the only tool in our kit to prepare our communities for climate change, there is virtually no downside to performing this restoration now, and a tremendous potential upside on the mitigation front. New studies are proving the ability of wetlands to sequester carbon in larger amounts than previously thought.

The good news is that wetland restoration is proceeding at a faster pace around the Bay than ever before, while a potential ballot measure by the Bay Restoration Authority in November could help our region start new projects that await funding and finish projects in progress now.

Here’s a status update on several prominent planned and in progress restoration projects that hold the greatest potential to protect communities from sea level rise and flooding caused by climate change:

Bair Island – Since being saved from development in the 1990’s, Bair Island has been a focal point of restoration in San Francisco Bay. Last spring, a pedestrian bridge was installed to connect Inner Bair with Uccelli Blvd, and project managers expect to formally complete restoration of Bair Island’s 3,000 acres this fall. Bair Island is in Redwood City, a low-lying city of 79,000 people. Its restoration will be an important part of Redwood City’s readiness for sea level rise.

Hamilton Field – A model for reuse, Hamilton Field was once a bustling military base along the Marin County shoreline. Earlier this spring, the decade-long restoration project was completed, returning this site to its natural state. Hamilton is north of San Rafael and adjacent to Bell Marin Keys, a community of 700 homes that sits 10 feet or less above sea level.

Cullinan Ranch – Cullinan Ranch’s 1,500 acres of restorable habitat along Hwy 37 were saved from development in the 1980s. Situated north of the City of Vallejo, this site will provide much needed habitat while continuing to protect the highway from flooding and sea level rise.

Eden Landing – The 1,000+ acres of Eden Landing mix the remnants of industrial salt manufacturing with restoration to create 50 nesting islands for migratory shorebirds including the endangered California clapper rail. Public access trails are slated to open in 2015. Eden Landing is situated near the San Mateo Bridge.

Ravenswood Ponds – Adjacent to the Facebook campus at the foot of the Dumbarton Bridge in an area prone to flooding, Ravenswood is one of the most visible interactions between the Bay and the built environment. Major restoration was completed in 2010, but volunteers continue to work on restoring native plants to the site.

News of the Bay: May 9, 2014

Check out this edition of News of the Bay for breaking news affecting San Francisco Bay

4/22/2014
San Jose Mercury News
Failure of Warriors Waterfront Arena Latest in Long Line of Bay Development Defeats
The Golden State Warriors’ decision this week to abandon plans to build a new arena on piers along the San Francisco waterfront is not just a local development issue, but rather the latest example of a 40-year trend around San Francisco Bay.
No matter how rich or how politically connected, people who have proposed projects that environmentalists say are “filling the bay” or “walling off the bay” have nearly always seen those plans end in defeat.
Read More>>

News of the Bay

4/22/2014
San Francisco Chronicle
Warriors Find they Can’t Beat the Bay
The San Francisco Bay wins.
That’s what Joe Lacob and the Warriors learned. Their plans for a waterfront arena foundered, despite endless bluster, almost from the start of planning and now apparently have been abandoned.
Read More>>

5/7/2014
San Francisco Chronicle
Global Warming Threat to West Spelled out in Report
Dwindling water for farms, longer fire seasons and coastal flooding of homes and businesses await California as climate change intensifies, according to a federal report released Tuesday that details how global warming is damaging every region of the country.
The third National Climate Assessment, compiled over four years by more than 300 scientists at the direction of Congress, said California’s farm industry, which provides more than half the nation’s fruits, nuts and vegetables, is particularly vulnerable. So are many cities along the coast, including San Francisco, that are already experiencing flooding at high tides as sea levels rise.
Read More>>

5/6/2014
KGO Radio
Santa Clara Bans Styrofoam Containers
On May 6, The Santa Clara City Council voted to ban Styrofoam food containers. As one of the last large cities in the South Bay to take this step, this is a big deal. As of this week, 62% of Bay Area residents live in a community that has banned Styrofoam food ware. The Bay Area has made great progress on bag bans too. Right now 76% of Bay Area residents live under a plastic bag ban.
Listen Here>> 

Stormwater is the Largest Source of Bay Pollution

Storm drain clogged with trash and debris.
Storm drain clogged with trash and debris.
Photo Credit: Mike Dillon.

Storm drains prevent flooding by draining excess water out of our neighborhoods, streets, and highways and carrying the water through pipes and culverts to nearby creeks that lead to the Bay.

Unfortunately, a lot more than just clean rain water flows to the Bay through our storm drains.  Last week a clogged plastic sewer pipe in Sausalito caused more than 50,000 gallons of raw sewage to spill into San Francisco Bay.  The sewage ran across the sidewalk, into a gutter, and down a storm drain that leads to the Bay 40 feet away.

While incidents like this happen from time to time and generate coverage in the news, storm drains carry toxic pollutants and trash into the Bay literally every time water flows through them.

Contaminants

The recently released “Pulse of the Bay” report found chemicals like pesticides, insecticides, and flame retardants in San Francisco Bay at levels that could pose hazards to aquatic life.

Pollutants enter the Bay through a variety of sources, including wastewater treatment plants, factories, and agriculture.  But according to the San Francisco Bay Regional Water Quality Control Board, stormwater is now the largest source of surface water pollution to Bay area waters.

Much of this pollution comes from our streets.  Cars discharge harmful metal particles like lead, zinc, and copper, and leak more oil into the Bay each year than the Cosco Busan oil spill did in 2007. Even the streets themselves contribute directly to the pollution problem.  Asphalt is held together with “recycled” petroleum products and waste from refineries, byproducts that would otherwise require safe disposal.  These toxic substances and the sealants used to coat paved surfaces leach into our waterways over time.

Trash

At this year’s annual Coastal Cleanup Day on September 21st, volunteers got to see first-hand how trash enters the Bay through our storm drains and creeks.  First Flush, the first big rain of the season, washed trash from the streets right into the creeks and wetlands we were cleaning up.

Some streets and highways are so full of litter that storm drains become clogged with trash and other debris, resulting in flooding.  Caltrans spends $50 million each year picking up litter on the streets, and has invested more than $5 million in the last five years to improve drainage on Highway 101 and I-80.

Plastic bags and Styrofoam food containers are some of the biggest offenders, which is why we’ve prioritized plastic bag and Styrofoam bans throughout the region over the past several years.  Recently we’ve turned our attention to the nearly 3 billion cigarette butts littered in the Bay area each year.  We’re investigating the best local policy options to address the largest single source of litter in the Bay area.  In the meantime, we’re also calling on tobacco companies to take responsibility for the toxic litter they produce.  Sign our petition to tell tobacco companies – Keep you butts out of our Bay!

Learn more about water pollutants and how you can help keep our Bay clean and healthy.  

City’s Plan Would Pave Bay Wetlands with Golf Course, Nearly 500 Houses

Photo of Area 4
Historic Bay tidal marsh, Newark’s “Area 4,” is one of the largest areas of restorable, undeveloped baylands in the South Bay (Photo by Margaret Lewis)

Should a bayside city work to help expand the San Francisco Bay National Wildlife Refuge, restoring more than 400-football fields-worth of Bay wetlands and habitat? Or should they forever destroy that opportunity by filling in the area with an 18-hole golf course and nearly 500 single family houses?

Those are the choices right now in the City of Newark – a shoreline city of 40,000 next to Fremont. Rather than recognize the incredible opportunity to protect the Don Edwards S.F. Bay National Wildlife Refuge, endangered species, and migratory bird habitat, Newark is seeking approval to fill in over 300 acres of historic baylands, including nearly 100 acres of wetlands and aquatic habitat, sprawling the city into a FEMA-designated flood zone.

Environmental organizations and regulatory agencies have long stressed to Newark of the ecological importance of 550-acre “Area 4” – one of the largest areas of restorable, undeveloped baylands in the South Bay:

  • The 1999 Baylands Ecosystem Habitat Goals Project, the scientific roadmap for the restoration of the Bay shoreline, identifies Area 4 as being uniquely situated for the restoration of both tidal marsh and adjacent upland transition zones, two habitats critical to the health of the Bay
  • Area 4 is host to approximately a dozen special status species –including the endangered Salt Marsh Harvest Mouse – and it is directly adjacent to Mowry Slough, a primary breeding ground for San Francisco Bay Harbor Seals
  • The San Francisco Bay Regional Water Quality Control Board has stated that “large expanses of undeveloped uplands immediately adjacent to tidal sloughs are extremely rare in the south and central San Francisco Bay” and that “Area 4 represents a rare opportunity to … provide an area for tidal marsh species to move up slope in response to sea level rise”
  • Similarly, the California Department of Fish and Wildlife have stated that “this wetland is an integral component of the San Francisco Bay ecosystem,” and “critically important to waterfowl and shorebirds.”

Yet Newark has ignored these concerns, proposing to fill in these rare wetlands and wildlife habitat with 2.1 million cubic yards of fill – enough dirt to fill nearly 100 trucks a day for two years straight!

The City should focus future growth within already developed areas, near transit, shops and services, not on ecologically-sensitive, restorable baylands at risk from flooding and sea level rise.

Update 10/11/2013: 

Opposition to Newark’s plan to build as many as 500 houses and an 18-hole golf course on one of the largest pieces of restorable Bay shoreline in the South San Francisco Bay is growing. More than 2,000 Bay Area residents submitted comments to the city on its General Plan. You added your voice to the chorus of opposition from regulatory agencies including the U.S. Fish and Wildlife Service (USFWS), the Bay Conservation and Development Commission (BCDC), and the Water Board.

A letter submitted by Don Edwards San Francisco Bay National Wildlife Refuge (USFWS) staff stated, “the proposed development of Area 4 will only add to the cumulative loss of tidal wetlands in San Francisco Bay and endangered species that are dependent on that habitat.”

Your support also helped us convince several environmental organizations to send letters of opposition, including Center for Biological Diversity, Defenders of Wildlife, and Greenbelt Alliance. Thanks to you, Newark’s plan will not go unnoticed much longer. Sign up here for updates on next steps.