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By By Bettina Boxall
Los Angeles Times
January 12, 2007
In proposing two big, expensive dam projects this week, Gov.
Arnold Schwarzenegger made a novel argument to justify the
old-fashioned public works projects.
Advocating $4 billion in bonds to build reservoirs in Northern
and Central California, the administration emphasized not
population growth or the specter of future drought, but global
warming.
As temperatures rise, California's mountain snowpack will
shrink, leaving a storage void the administration says should
be filled in part with new reservoirs.
"This administration is taking the lead in this country
to deal with greenhouse gases," state Department of Water
Resources Director Lester Snow said. But "no matter what
we do now, we continue to have changes in snowpack and runoff
patterns."
Each 1-degree rise in temperature pushes the mountain snow
line 300 feet higher, meaning that as California warms, more
precipitation will fall as rain in winter storms and less as
slow-melting snow, increasing the flood threat and making it
harder to capture mountain runoff.
"The forecast — and these are fairly conservative
forecasts," Snow said, "is that by 2050 we will have
lost 25% of the snowpack in the Sierra…. If we don't take
management action to accommodate that, we will wind up with
both flood and water-supply issues."
GOP-backed administration proposals for new water storage
projects sank last year amid Democratic opposition, and dam
proponents said the chances of getting the reservoir plans
through the Democrat-controlled Legislature this year are
slim.
"I think we know a bit more about the effects of climate
change in California," said Steve Hall, executive
director of the Assn. of California Water Agencies, which
supports new reservoirs. "But in the end I'm not sure it
is enough to convince a majority of legislators to vote for
it."
Both proposed reservoirs have been under consideration for
years.
One would dam canyons and flood 14,000 acres of ranch country,
including the tiny Colusa County settlement of Sites, 77 miles
north of Sacramento. To lessen environmental damage, the
reservoir would not be constructed on the Sacramento River but
some 16 miles to the west.
Existing irrigation canals or a new billion-dollar pipeline
would carry water from the river to the reservoir, which would
hold roughly 1.8 million acre feet of water, less than half
the capacity of Shasta Lake, the state's biggest reservoir.
The second reservoir, called Temperance Flat, would be built
on the San Joaquin River east of Fresno, just upstream from
the existing Friant Dam and Millerton Lake.
It would hold up to 1.3 million acre feet.
"I think we need more storage anyway for dry years, and
climate change just makes it worse," said the state's
chief hydrologist, Maury Roos.
Sen. Darrell Steinberg (D-Sacramento), who heads the Senate
Natural Resources and Water Committee, which would review the
reservoir package, said alternatives for developing new water
supplies, such as ground water storage and conservation,
should be evaluated.
Moreover, Natural Resources Defense Council policy analyst
Barry Nelson said the Temperance Flat reservoir is in the
wrong place to counter the effects of global warming because
the high peaks of the Central and Southern Sierra are expected
to experience less snowpack loss than mid-elevation mountains
to the north.
"It's more subsidized water for [agricultural] users in
the San Joaquin Valley," Nelson contended. "It has
nothing to do with climate change."
He also said the Sites reservoir would leave water supplies
vulnerable to another aspect of global warming: rising sea
levels in the Sacramento-San Joaquin Delta.
Water delivered to the south would have to go through the
delta, which will get saltier as rising sea levels push ocean
water farther upstream.
Jeffrey Kightlinger, general manager of the Metropolitan Water
District of Southern California, said that although both Sites
and Temperance Flat "would be useful, they are not,
either one, really aimed at Southern California and our
issues."
More important for the region, Kightlinger said, is dealing
with the many problems of the delta, which is where Northern
California water is diverted south.
Delta levees could collapse in an earthquake, letting in more
seawater, and a dramatic decline in delta fish populations
could force changes in the pumping operations that send water
south.
"We are quite concerned with our ability to move water
through the delta and so without progress on conveyance issues
in the delta, it's unclear what value surface storage north of
the delta would have," Kightlinger said.
The administration is expected to soon appoint members of a
blue-ribbon commission to examine delta issues and, along with
the reservoir funding, is proposing $1 billion in bonds for
delta projects.
The water package also includes $500,000 for local groundwater
storage projects. And Snow indicated this week that the
administration would be open to discussing a greater emphasis
on ground water storage.
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