Published Sunday, February 18, 2007, by the San Francisco Chronicle

CONSEQUENCES OF A RISING BAY

GLOBAL WARMING: New set of maps reveals how melting polar ice could
change shoreline and carry a high price for entire region

By Jane Kay
Chronicle Environment Writer

New maps show that neighborhoods and roads in many cities near the
San Francisco Bay shoreline would be under water if global warming
causes tides to rise as much as 3 feet in the coming decades, and
officials say regions face key decisions about where people will be
able to live and build.

The maps, which the Bay Conservation and Development Commission
prepared for The Chronicle, offer a detailed look at how a changing
shoreline would affect life around the bay.

Parts of Corte Madera, San Rafael, Hayward and Newark and much of the
Silicon Valley shoreline would be under water, including a portion of
Moffett Field, the site of NASA Ames Research Center, where Google
wants to build a 1 million-square-foot campus.

On the edge of the rising waters would be stadium sites proposed for
the 49ers -- in Santa Clara and at the Hunters Point Shipyard in San
Francisco. Fremont's proposed site for the Oakland A's ballpark also
could be vulnerable to flooding in the 21st century, the maps show.

Wastewater treatment plants for more than a dozen cities in the South
Bay, including San Jose, and the industrial ponds for the Valero oil
refinery in Benicia and the Chevron refinery in Richmond, would be
inundated by the projected rise in the bay.

While the Bay Area has done a good job designing for earthquakes,
it hasn't done so for sea-level rise, said Will Travis, executive
director of the bay conservation agency, which approves shoreline
development. Aside from cutting greenhouse gas emissions, Travis
said, "The amount of planning and preparing that we do is really
what will affect how severe the impacts are here."

Cities can protect vulnerable shorelines with sea walls and levees,
but the fixes and maintenance would cost billions of dollars.
Officials will have to decide what to save and what to let go. Some
development plans in the works may have to be shelved or drastically
re-engineered, Travis said.

The maps illustrate the regions of risk. Among the areas threatened
are:

-- In the North Bay, low areas include Bel Marin Keys, parts of
Highway 37 and much of the former Hamilton Air Force Base around
Black Point. Parts of Highway 101, Mill Valley and Sausalito would
be flooded. Sections of Corte Madera would be under water, as would
southern San Rafael.

-- On the San Francisco shoreline, vulnerable spots include parts
of Mission Bay housing and office developments, Caltrain tracks,
Candlestick Point redevelopment, Heron's Head Park and the city's
sewage-treatment system on Islais Creek. Parts of Treasure Island
and the San Francisco and Oakland airports would be under water.

-- Foster City and parts of San Mateo, Redwood City, Mountain
View and Palo Alto would be flooded. Waters would inundate sewage
treatment plants located in Palo Alto, Sunnyvale and Alviso, which
serve dozens of cities and thousands of businesses. Parts of
Shoreline Park at Mountain View would be at risk of flooding.

-- Parts of Alameda, San Leandro, Hayward, Union City, Fremont
and Newark, including sections of Interstate 880, would be covered
with water.

-- The Richmond Parkway and parts of Richmond and San Pablo are
vulnerable to rising bay water, as is the enormous West County
landfill.

Areas of greatest risk

The new maps showing a 1-meter rise shouldn't be used for specific
planning purposes, the bay agency's representatives say, although the
maps indicate which regions of the shoreline are at the greatest risk
of incremental inundation.

Just how fast or how high the oceans might rise in the coming decades
are points of uncertainty among climate scientists. Most models don't
take into account the recent increasing rate of melt in Greenland and
sloughing of ice in western Antarctica. Nor can they project with
much confidence the amount of expansion of ocean waters as they warm.
At this point, models show a range of rise from 0.5 meter to 5 meters
by 2100.

The problems for a metropolitan estuary are enormous. Topping the
list is saltwater flowing up into the Sacramento-San Joaquin River
Delta, where pumps send fresh water to two-thirds of Californians.
Homes, businesses, highways, groundwater and wetland habitat would
be flooded.

Sea water would inundate dozens of industrial and municipal
wastewater systems ringing the bay, disrupting treatment. Another
worry is old shoreline dumps and military installations that could
leak biological and chemical contaminants into the bay if soaked.

"Since the bay isn't going to rise over night, the landfill owners
can extend dikes, as well as design for flood control, as part of a
maintenance program," said Curtis Scott, chief of the ground water
and waste contamination division of the San Francisco Bay Regional
Water Quality Control Board.

For example, bay waters would lap up around the big West County
landfill off Richmond in the event of a 1-meter rise. The owner,
Republic Industries, already has dug down into the bay and built
walls around it. The wall could go higher, Scott said.

Lila Tang, the regional board's division chief of wastewater
permitting, said municipal and industrial wastewater treatment plants
are at risk because they're generally at the low spots on the edge of
the bay.

Difficult solutions

Protecting them "isn't as simple as building a berm or seawall around
a sewage treatment plant," she said. "If the bay water rises, the
operators would have to install additional pumping capacity to force
the treated water out to a higher bay." Other problems would be
backflow into the system or a rising groundwater table that would
allow seepage into the collection system.

There are no current cost figures of what's at stake. In 1990, the
Pacific Institute, an Oakland independent think tank, determined that
a 1-meter rise would threaten $48 billion in residential, commercial
and industrial property. Constructing new levees and seawalls,
raising buildings, freeways and railroads and replenishing beaches,
according to the estimates then, would exceed $940 million with $100
million a year to maintain.

Officials from the bay conservation agency and the Pacific Institute
are seeking funds to conduct a study to identify real estate,
infrastructure and natural resources at risk, and calculate the
costs.

Perhaps hardest hit would be the South Bay and Silicon Valley, where
government agencies and property owners have started to look at ways
to reduce flooding. Some parts of Santa Clara County have dropped 14
feet as the ground sank when groundwater was pumped from the 1940s
to 1960s. Agricultural lands in the North Bay and delta islands have
also dropped.

The U.S. Army Corps of Engineers is poised to play a part in levee
construction, and is conducting a study of South Bay shoreline
flood-control with agencies including the Santa Clara Valley Water
District. The work will be done in conjunction with the major
transformation of some 15,000 acres of salt ponds into tidal marsh.

Few fears for sports teams

Some businesses are more concerned than others. Forty-niners
spokeswoman Lisa Lang said the team owners "are aware of the
predictions and the many variables associated with them" at a Santa
Clara site under consideration for a new stadium. But she said the
owners believe that if the site is feasible, "it will provide decades
of enjoyment for our fans."

The Oakland A's plan to build a ballpark in Fremont at one of the
sites at risk of rising tides. Team spokesman Jim Young has said
that if the owners thought the water was a problem, they wouldn't
be going ahead with planning for a Fremont park.

Officials at the NASA Ames Research Park on Moffett Field are
actively working with the Corps of Engineers and others to plan levee
protection from sea-level rise, said Sandy Olliges, deputy director
of the environmental office. Already home to dozens of businesses,
nonprofits and universities, NASA Ames is planning to build the
world's largest concentration of high-tech companies, including the
Google campus.

But few of California's coastal cities and counties have taken action
to prepare for rising tides, said Susanne Moser, a research scientist
at the National Center for Atmospheric Research in Boulder, Colo.,
who surveyed 300 planners, public works engineers and other officials
from city and county governments last year.

Only one city, Berkeley, and two counties, Sonoma and San Luis
Obispo, had in place some plan that considers the effects of global
warming. San Francisco, Alameda, Palo Alto, Solana Beach (San Diego
County), Goleta (Santa Barbara County) and the counties of Contra
Costa, Marin and Humboldt are preparing plans.

The officials who haven't acted blamed lack of money, staff and
support from the state and federal governments, as well as the press
of other obligations.

It's difficult for local officials to plan given the uncertainty of
how much sea levels will rise, said Harvard University Professor John
Holdren, president of the American Association for the Advancement of
Science, who is in San Francisco for the group's annual meeting.

But he said a new report expected next month from the United Nations
will proclaim that "prudence requires not building close to the
shoreline in the future."

Learn about climate change

Discussions of climate change and other events will be held at a free
Family Science Day today in San Francisco that is part of the annual
meeting of the American Association for the Advancement of Science.
The programs will be held in the Yosemite Room of the Hilton San
Francisco, 333 O'Farrell St., between 11 a.m. and 5 p.m. For more
information, go to aaasmeeting.org.

E-mail Jane Kay at jkay@...


[BATN: See also:

Grim global warming prognosis for Western U.S.
http://groups.yahoo.com/group/BATN/message/33582

Warming: California losing ground to rising seas
http://groups.yahoo.com/group/BATN/message/33549

Disturbing new warming report criticized as too optimistic
http://groups.yahoo.com/group/BATN/message/33547

Schwarzenegger may kill high-speed rail to widen roads, warm planet
http://groups.yahoo.com/group/BATN/message/33493

DAY 7: Warming debate shifts to what to do about it
http://groups.yahoo.com/group/BATN/message/33485

DAY 6: Warming-fueled 3-foot rise in seas poses $48b threat to SF Bay
http://groups.yahoo.com/group/BATN/message/33473

DAY 5: Warming could cause California animal extinctions, habitat loss
http://groups.yahoo.com/group/BATN/message/33450

DAY 4: Warming could devastate California trees, plants
http://groups.yahoo.com/group/BATN/message/3342?

DAY 3: Warming could crush California wine industry
http://groups.yahoo.com/group/BATN/message/33420

DAY 2: Warming threatens California snowpack, water supply
http://groups.yahoo.com/group/BATN/message/33375

DAY 1: California is especially vulnerable to global warming
http://groups.yahoo.com/group/BATN/message/33374 ]

etc. ]