WSP11116

• File Number: 8056
• Description: Drought Preparedness
• State: CO
• Basin: Statewide
• Date: 2/1/1976
• Author: Dept of Water Resour
• Title: Special Report on Dry Year Impacts in California
• Water Supply Pro - Doc Type: Report/Study

The 1928-34 dry pel:iod probably had the greatest impact
because of the cumulative effects on the dry farmed community
coupled with the increased irrigated agriculture which suffered
from lack of streamflow to divert for crops. The State Water
Plan of 1930 proposed the beginning of what is now the Central
Valley Project. The State did not have the financial capacity
to proceed with construction and by the mid-30s it was clear that
the proposed large water projects such as Shasta Dam were needed.
The Federal Bureau of Reclamation began in the 1940s to build
many of the Central Valley dams that are supplying agricultural
and other needs this year. The dry years in the late 40s and
again in the 60s caused less impact because of the larger number
of water storage projects. The invention of the deep well tur-
bine about 1910 and its expanded use in the middle of this
century made ground water more readily available, in both dry
and wet years.

The relationship between water supply and electrical
energy came home to California in 1946-47. That year was
notable for both its adverse impact on agriculture and for
the brownouts resulting from a deficient supply of electrical
power. Much of the electrical power in Northern California at
that time was supplied by hydroelectric plants as contrasted
with the present situation where about 80 percent of the
electricity is generated by steam plants fueled by fossil fuels
and nuclear energy. Following the 1946-47 water year 1947-48
also began as a dry year and great concern was felt for agri-
culture, public water supply for many communities, and avail-
ability of electrical power. Fortunately, heavy rains began
in February and, as in 1974-75, those concerns were washed away.

Areas in California not served by these large surface
water storage projects or from the large ground water basins
have, and will continue to have, problems in a dry period. The
climate of this State is extremely variable as illustrated
in the histogram of the precipitation pattern at Sacramento,
Figure 1. Surface storage reservoirs and conjunctive use of
ground and surface water, coupled with good water management,
is necessary'to bridge the dry years much as our flood control
reservoirs and levee and bypass systems take care of the wet
flood years.

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