(Bloomberg) — California would need enough water to fill
16.7 million Olympic-sized swimming pools to recover from its
historic drought, NASA scientists using satellite data estimate.
Water storage in the state’s Sacramento and San Joaquin
river basins was about 11 trillion gallons below seasonal levels
during the peak of the three-year drought, the National
Aeronautics and Space Administration said today in a statement.
An Olympic-size pool contains about 660,000 gallons of water.
Scientists used satellite data collected since 2002 to
calculate how much of a water deficit California was suffering
from and what volume would be required to end the drought. Data
showed that since 2011, the Sacramento and San Joaquin river
basins decreased in volume by 4 trillion gallons of water each
year — more water than California’s 38 million residents use
annually for household and municipal purposes, NASA said.
About two-thirds of the loss since 2011 is from groundwater
reserves feeding agricultural demands from the Central Valley.
“Space-borne and airborne measurements of Earth’s changing
shape, surface height and gravity field now allow us to measure
and analyze key features of droughts better than ever before,”
Jay Famiglietti, a water scientist at NASA’s Jet Propulsion
Laboratory and a University of California at Irvine hydrologist,
said in the statement.
California was battered this week by a severe storm that
caused flash flooding, grounded flights and halted public
transit. The state needs at least more five storms of that
magnitude before the drought can be considered over.
New drought maps also show groundwater levels across the
U.S. Southwest are in the lowest 2 to 10 percent since 1949.
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