by Jay Thorwaldson
Climate-change deniers notwithstanding, California officials are convinced that one major climate-change effect — rising sea level over the next few decades — is already happening and is inevitable.
And a rising sea means a rising bay, which will directly threaten the South Bay, with its weak salt-pond dike system (piled-up mud, not real levees) and serious land subsidence from past decades of over-pumping groundwater.
The real damage comes not from the rising water but from higher tides combined with storms or wind-pushed tidal surges. One official said it's not the filling of a bathtub that does real damage; it's when your 2-year-old cannonballs into it.
Increased weather volatility is another climate-change side effect, so expect cannonball storms and tsunamis.
Lowland portions of Palo Alto, the southeast quadrant that has flooded in recent years, is doubly vulnerable: from bay overflow and creek overflows, despite sky-high property values.
San Mateo County is doubly threatened, Assemblyman Rich Gordon — who represents much of the county and chairs the Assembly's Select Committee on Sea Level Rise — observed at a special committee hearing in mid-January. The county faces rising sea and bay on both sides, while other low-lying parts of his district further south are also threatened.
Scientists estimate there will be a rise of 15 to 17 inches by 2050 and about 55 inches by 2100 — but those are soft estimates a long way off, and officials are advising people to expect at least a 3-foot rise by 2050. At least.
Yet that's also a long way off, and it's hard to generate a sense of urgency among the public — or local officials — with that long a lead time, and when uncertainties remain about how high the rise will be.
And taking effective action will require a major investment of effort and funds, a big deterrent.
But a parade of state and regional officials said that now is the time to plan and the time to act: The rise is already happening and future damage will cost far more than near-term preparation and prevention. There are 61 coastal cities in 15 coastal counties at risk, officials noted.
A report is due out by mid- to late-March, delayed from an earlier target of late February.
Officials from the San Francisco Bay Conservation and Development Commission, Natural Resources Agency, California Coastal Commission, State Lands Commission and the Coastal Conservancy were unanimous in their conviction that the rise is real and happening now, and that action is required.
Some response mechanisms are already in place, such as the "Adaptation to Rising Tides" program, or ART, which focuses on strategies to monitor and reduce impacts — a joint program with the Association of Bay Area Governments (ABAG).
Zachary Wasserman, chair of the Bay Conservation and Development Commission (BCDC) board, expressed urgency about a lagging response.
Despite years of talk about sea-level rise, fewer than half the homes around the bay or California coast are prepared for the "slow-moving emergency" or rising sea levels, he warned.
He called it a "daunting challenge" to bring together government agencies and private entities to create effective responses.
"It's time to start now," he said, citing the recent creation of a "Rising Sea Level Working Group" of state and local officials charged with launching a unified campaign by next fall. Questions the group must address include "What can we do?" "What should we do?" and "How do we pay for it?"
"It's critical to understand that we don't have all the answers," Gordon said at the hearing.
BCDC has compiled a set of detailed maps showing areas threatened by rising sea levels, and has sponsored a "Rising Tides Architectural Design Competition."
"It's one of the critical issues of our time and for future generations," Charles Lester, executive director of the California Coastal Commission, said.
He cited the severe damage caused by the tsunami from Japan's earthquake in Crescent City and elsewhere as an example of future events that would be far worse with higher sea levels. It was a low tide when the wave hit Crescent City, where officials have now started to plan for a 3- to 6-foot sea-level rise.
Some coastal developments have started building concrete sea walls to prevent erosion of bluffs, such as the loss of 90-feet of land at Lands End in Pacifica. But sea walls cause beaches to disappear as the sand migrates down the coast. Broad Beach in Malibu "is no longer broad," Lester said, and public-access easements simply disappear into the sea.
There is a push under the state's Coastal Act to have local governments prepare Local Coastal Programs, or LCPs, to address responses to erosion, but most don't address sea-level rise, Lester said. And they are lagging in adequacy, he added.
While there are no easy solutions, one answer is to create a stronger "coastal resiliency," which can include banning sea walls or removing them. In one case, when a sea wall was removed the sand returned, he said.
John Laird of the Natural Resources Agency said there is acute risk to many low-income communities, as well as to sewage-treatment plants, roads and other public and private facilities. With a higher sea level, a single big storm could cost "in the high hundreds of billions," he warned.
One possible, or partial, solution for protected areas such as the San Francisco Bay, might be to expand marshlands along the shore, where plants such as cord grass could help absorb the shock of storm waves and surges and protect the levees.
Concern about flooding is not new to the South Bay and Palo Alto. In the mid-1970s, I wrote about a study proposing the improvement of salt-pond dikes winding around the bay, at an estimated cost of $95 million. But engineers instead suggested a 6-foot concrete wall on the inland side of the marshes. The public balked at losing the view of and access to the baylands, and the plan died.
Today's far bigger slow-moving emergency deserves a better fate.