FRESNO,
Calif. (AP) — Land in Central California's agricultural region is
sinking so quickly because of the state's historic drought that it is
forcing farmers to spend millions of dollars upgrading irrigation canals
and putting roads, bridges and other infrastructure at risk.
Associated Press
California land quickly sinking in drought costs farmers
This July 23, 2015 photo
provided by the California Department of Water Resources shows The
Russell Avenue bridge, over the Delta Mendota Canal in Firebaugh,
Calif., The drought has caused the bridge to subside until there’s
almost no space between bottom of bridge decking and canal water
surface. A NASA scientist says in a report released Wednesday, Aug. 19,
2015 that parts of California’s Central Valley are sinking faster than
ever as groundwater is being pumped during the state’s historic drought.
(Florence Low/ California Department of Water Resources via AP)
FRESNO, Calif. (AP) — Land in Central California's
agricultural region is sinking so quickly because of the state's
historic drought that it is forcing farmers to spend millions of dollars
upgrading irrigation canals and putting roads, bridges and other
infrastructure at risk.
The Central
California Irrigation District recently spent $4.5 million to raise the
walls of a canal, and the district's manager, Christopher White, says
they're about to invest another $2.5 million to replace a bridge that's
now below the canal's water line.
"It's
a vivid picture of what subsidence can do," said White, who serves
1,900 farmers on the San Joaquin Valley's west side that grow crops such
as tomatoes, cotton, fruit and almonds in three counties.
Sinking
land has occurred for decades in California because of excessive
groundwater pumping during dry years, but NASA data released Wednesday
by the state's Department of Water Resources shows the pace has
dramatically quickened as the state endures its fourth year of drought.
The
study done by NASA's Jet Propulsion Laboratory shows the ground is
sinking nearly two inches each month in some places, placing roads,
bridges and vital canals that deliver water throughout the state at
growing risk of damage.
"We are pumping at historic levels," said
Mark Cowin, head of the California Department of Water Resources, adding
that groundwater levels are dropping to record levels — up to 100 feet
lower than previously recorded.
Gov.
Jerry Brown signed historic legislation last year that requires
monitoring of groundwater pumping. However, local officials have until
2020 and in some cases until 2022 to write their management plans, so it
could take another decade or two before California has a handle on
groundwater use, Cowin said.
"I don't think we can end overdraft or subsidence overnight," he said. "We do need to take action."
Meanwhile,
the state is launching a $10 million program to help counties with
stressed groundwater basins to develop or strengthen local ordinances
and conservation plans.
The NASA data showed land near the city of
Corcoran sank 13 inches in eight months, and part of the California
Aqueduct dropped eight inches in four months last year. The aqueduct
provides water to million people and vast farmland in the nation's most
productive agricultural state.
NASA's satellite imagery shows a
problem that farmers in White's irrigation district have long known. To
keep water flowing, they raised the canal walls in order to send higher
levels of water, overcoming a drop in elevation. The higher flow also
put the bridge below the water line.
Long-term
subsidence has already destroyed thousands of public and private
groundwater well casings in the San Joaquin Valley. Over time,
subsidence can permanently reduce the underground aquifer's water
storage capacity.
Lester Snow,
executive director of the California Water Foundation, which promotes
water policy, urged more immediate action. He said state and federal
officials should offer local agencies financial incentives to reduce
pumping.
Investments are also needed in storm water capture during wet winters to offset heavy reliance on groundwater, Snow said.
"As long as this continues, we risk further damage to roads, levees and buildings," he said. "There is no time to waste."
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