Its construction authorized by the Rivers and Harbors Act of
1937, the massive Central Valley Project
(CVP) encompasses 20 reservoirs with a combined storage capacity
of 11 million acre-feet, eight power plants, two
pumping-generating plants and some 500 miles of major canals and
aqueducts. In a normal year, the CVP delivers 7 million acre-feet
of water to about 3 million acres of farmland in the Central
Valley.
About 30 percent of California’s total annual water supply comes
from groundwater in normal
years, and up to 60 percent in drought years. Local communities’ usage
may be different; many areas rely exclusively on groundwater
while others use only surface
water supplies. Contrary to popular opinion, groundwater does
not exist in underground lakes.
