News
Bay Area environmental group proposes hybrid levees for bay
Chris Palmer, San Mateo Times
As global warming escalates, San Francisco Bay's existing flood protection system will be no match for rising sea levels. But according to a new report by a Bay Area environmental group, fortifying the bay's shoreline with levees fronted by restored tidal marshes will be a cheaper, more aesthetic and ecologically sensitive alternative to traditional levees.
The Bay Institute's report proposes restoring tidal marshes with sediment from local flood control channels and irrigating the marshes with treated wastewater. The plan also calls for "horizontal levees" that are a hybrid of traditional earthen levees and restored marshes.
Tidal marsh restoration in the bay has been a priority for environmental groups since the 1970s. More than 5,000 acres have been restored in the past two decades, with another 30,000 acres purchased and slated for restoration.
"Marshes act as the lungs of the bay," said John Bourgeois, manager of the South Bay Salt Pond Restoration Project. "They can clean and filter the water that comes down our tributaries before it hits the bay."
The tall, dense vegetation of tidal marshes can also absorb a significant amount of the energy of surging ocean waves during storms. "The concept is a good one. The physics of it are accurate," said Lisamarie Windham-Myers, a wetland ecologist at the U.S. Geological Survey. "It's been proven over and over that wetlands help reduce storm surges." Therefore, she said, levees don't have to be as tall.
The Bay Institute estimates that shorter levees fronted by tidal marshes would bring down the cost from more than $12 million to less than $7 million per mile, while providing the same level of flood protection. With 275 miles of bay shoreline to protect, total savings could eventually exceed more than a billion dollars.
"We knew the cost would be reduced, but we were shocked at the actual savings," said Marc Holmes, the Bay Institute's marsh restoration program director.
Funds to build and maintain levees have come over the years in piecemeal chunks from the federal government and local floodplain control agencies. The result has been a patchwork quilt of aging earthen levees, designed to protect against present-day sea levels.
The Bay Institute report was released about three weeks after U.S. Sens. Dianne Feinstein and Barbara Boxer reintroduced the San Francisco Bay Restoration Act, which seeks federal funding for wetland restoration and water improvement projects in the bay and its watershed.
"We hope we have now given them the ammunition to say, 'Look, this is not going to cost us money, it is going to save us money,'" Holmes said.
As carbon emissions cause the Earth to warm, polar ice melts and warmer ocean water expands. Already, sea levels in the bay rose 8 inches in the past century, leading to occasional flooding of major regional roadways such as state Highways 37 and 101 during winter storms.
According to a 2011 National Academy of Sciences report, sea levels off the California coast south of Cape Mendocino will rise another 1.5 inches to 11.8 inches by 2030, 4.7 inches to 24 inches by 2050 and 16.5 inches to 65 inches by the end of the century.
Even a moderate rise in sea level will likely lead to increases in flooding frequency and intensity. Developed areas particularly at risk are San Francisco and Oakland international airports and tech giants such as Oracle and Facebook.
Though rising sea levels are a concern, winter storms riding in on higher tides can cause the most havoc. "In the next century, we're going to get more storms, fiercer storms," Holmes said. "Locations that were once outside of the danger zone are now inside, simply because storms are arriving on higher sea levels."
The goal of the Bay Institute study was to find a way to build a cost-effective network of levees that could lessen the flood threat caused by storm surges, while also providing benefits to the environment. The South Bay Salt Pond Restoration Project is considering a similar "horizontal levee" for its Alviso flood protection plan, which will be released later this year.
"With Hurricanes Katrina and Sandy, it has been well-documented that tidal marshes in front of levee systems do a great job of absorbing storm surges and add significant amounts of flood protection to the built environment," Bourgeois said.
The Bay Institute report imagines tidal marshes filled with silt to create a gentle upward slope from the bay shoreline to the top of a wedge-shaped earthen levee. Near the levee, tall, quick-growing plants with deep root systems would be irrigated with wastewater from nearby water treatment plants.
The sloping marsh can slow down storm surges, and the dense vegetation can absorb it like a sponge. Using marshes to buffer storm surges means earthen levees built on the landward side of the marshes can be built half as tall. As the vegetation grows taller and the root systems expand, the horizontal levee will be able to protect against the rise in sea levels expected in the coming decades, provided the restoration begins sooner rather than later.
Nearly 150,000 of the 190,000 acres of the bay's tidal marshes that existed in 1850 have been destroyed by conversion to uses such as salt evaporation ponds and agriculture.
Efforts to restore a few thousand acres of marshes that began in the late 1970s have now evolved into the largest marsh restoration plan in the country, with the goal of restoring 100,000 acres. The bay marshes are home to endangered species that exist nowhere else, as well as the largest estuary on the western coast of North and South America.
The Bay Institute report also recommends that Congress allocate $1 billion to establish a program administered by the Environmental Protection Agency that would coordinate the various efforts to restore and protect the bay.
Congress has established a handful of comparable programs for nationally important regions such as the Great Lakes and Chesapeake Bay.
"Obviously," Holmes said, "we could make that case in San Francisco Bay persuasively."
Representative Anna Eshoo Responds to RCNU Supporters’ Letters Opposing the Saltworks Project
Redwood City Neighbors United's membership continues to engage with elected leadership on the local, state, and national level. Representative Anna Eshoo recently responded to RCNU members' letters opposing the Saltworks project and urging oversight of Cargill's recent jurisdictional determination request:
Thank you for contacting me about potential uses for, as well as federal jurisdiction over, Cargill 's Redwood City salt production land. I welcome your input on this very important issue.
Because of the unique location of this property near San Francisco Bay, any decisions regarding its future use should respect the community 's environmental concerns . As you might know, I was successful in securing funding to purchase Bair Island (which also was used for salt production) and made it part of the Don Edwards San Francisco National Wildlife Refuge. I've monitored this issue very closely for several years and continue to do so.
I was especially interested to hear your concern about the Army Corps of Engineers' and the Environmental Protection Agency's jurisdictional review processes. You can rest assured I will keep your views in mind.
If you have any other questions or comments, let me hear from you. I value what my constituents say to me, and I always need your thoughts and benefit from your ideas.
...
Most gratefully,
Anna G. Eshoo
Member of Congress
LTE: City rightly says ‘no’ to building on the bay
Published in the Palo Alto Daily News
As a resident of Redwood City, I am pleased to see that it is implementing its award-winning and community-driven general plan in a way consistent with the plan's mandates -- making our downtown a higher-density, pedestrian-friendly one that is attractive to new residents, local businesses, and longtime community members. A revitalized downtown with housing near public transport hubs and within existing infrastructure is where Redwood City should continue to focus its efforts. Building out on the salt ponds stands in direct opposition to this and does not represent the community's new vision for responsible growth. Redwood City's message is loud and clear -- any new plan Cargill and DMB might propose for building on the bay will be a nonstarter.
Nancy Arbuckle
Redwood City
Redwood City Neighbors United 2012 Review
2012 was a busy year for Redwood City Neighbors United and our first full year of working together as Redwood City residents to oppose the Saltworks project. As 2013 begins, let’s take a look back at a few of the important news stories from 2012.
- In March, RCNU’s first membership meeting of the year featured Blake Lyon, Acting Planning Manager for the City of Redwood City, who discussed Redwood City’s general plan with residents. The Saltworks plan falls outside of the general plan and is a distraction to the improvement of the rest of Redwood City. RCNU and its supporters remain committed to supporting the general plan and opposing the Saltworks.
- Faced with significant community opposition, Cargill and its developer, DMB, pulled its plan for the Saltworks in early May after three years of controversy.
- While withdrawing the plan, Cargill and DMB promised to submit a revised plan. Since then, they have gone straight to federal agencies in an attempt to circumvent the local opposition and controversy, requesting a jurisdictional determination from the EPA and the Army Corps of Engineers. To help educate our members about why this jurisdictional determination matters, we held a second membership meeting in November featuring Calvin Fong, the former regulatory division chief for the San Francisco district of the U.S. Army Corps of Engineers, who explained the jurisdictional determination process to a large crowd of concerned residents. Read about our meeting here.
- If you missed our meeting, check out this Op-Ed on why jurisdictional determination matters to you.
For a complete look back at the news of 2012, check out the RCNU website, visit our Facebook timeline, or our Twitter feed.
Heading into 2013, we await the jurisdictional determination from the EPA and the Army Corps of Engineers and remain ready to oppose a revised Saltworks plan if and when it is presented by Cargill and DMB. We continue to work to educate our local, state, and federal representatives about this ill-conceived development and we are already planning community meetings on this issue for 2013. Most importantly, we look forward to working with our neighbors to promote responsible growth, not Saltworks in 2013.
Happy New Year!
Redwood City Saltworks project waits in limbo while feds mull next course
By Bonnie Eslinger, Palo Alto Daily News
Back in May, DMB Pacific Ventures withdrew its controversial plan to develop 1,400 acres of Cargill's salt ponds in Redwood City until two federal agencies could clarify -- hopefully by the end of the year -- whether they have jurisdiction over the project.
DMB is still waiting for an answer, company Senior Vice President David Smith said Friday.
"We had hoped by the end of the year, but now we're hoping for the first quarter (of 2013)," Smith said in a phone interview. "We're anxious to see what they say."
The company has had several sit-down discussions with the U.S. Army Corps of Engineers and the Environmental Protection Agency, but so far the agencies have not indicated where they stand, Smith said.
If they side with DMB's argument that the vast majority of the Cargill site does not include "waters of the United States" and therefore should not fall under federal oversight, Saltworks won't have to comply with the Clean Water Act or the Rivers and Harbors Act, both of which tightly restrict the kind of development allowed on bayfront property.
Depending on the federal ruling, DMB is prepared to submit a scaled-back plan that proposes to build on about half of the original acreage and restore more wetlands than first envisioned, Smith said.
"We won't re-file with the city until we know their (the federal agencies') perspective," he said. "And until we get the clarity from the feds, we're not doing any elaborate planning."
Redwood City Senior Planner Blake Lyon said when DMB withdrew its application the city took time to archive its files but otherwise hasn't done any work on Saltworks.
The lull does not mean the project isn't alive, Smith said.
Meanwhile, Redwood City residents and environmental activists who want the Saltworks project stopped are not just waiting around to see what happens next. After years of fighting against the development, they're using the down time to gear up for the next round.
"We're going to be ready to roll and engage with the city, as we were before the project went dormant," said Gail Raabe, an organizer with Redwood City Neighbors United, which hosted a talk about Saltworks last month with a former Army Corps of Engineers official as the featured speaker. The group has about 400 members, she said.
The Saltworks project that DMB unveiled in 2009 included up to 12,000 homes, several office buildings, shops and schools on half of Cargill's property, with parks, open space and restored tidal marshes on the other half. At the time, company officials said they hoped to break ground in 2013.
David Lewis, executive director of Save the Bay, which has led the battle against Saltworks, said even though things have been quiet in recent months, arguments against building in areas at risk of flooding were underscored by the devastation wrought in New York and New Jersey by Hurricane Sandy.
"Building below sea level was always a bad idea," Lewis said. "I think people are now beginning to realize that."
