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Ground Water
Development
Ground
water yields comprise about 40 percent of the water in use
in California and comprises 17 million acre-feet per year in
usage. Geologists estimate that 90 percent of the
world's usable supply of water occurs as ground water.
Ground water usually occurs as water between pore spaces of
sediments and layers of these sediments of sand, gravel silt
and clay make up area aquifers. Ground water basins
underlie almost half of California's land areas.
Ground water has a number of advantages; it is not as likely
to be exposed to pollution as surface waters, reduced rates
of loss due to evaporation, and aquifers act as natural
filter systems removing disease organisms and sedimentation
(but not nitrates).
An examination of state and federal reports by the director
of technical services in the National Water Wells
Association in 1978, found that there are 20 million
acre-feet of water basins beneath Sonoma County. He
stated that the yield would be 200,000 acre-feet per year
without threat of depleting the aquifers. Then SCWA
chief engineer, Gordon Miller disputed the fact and
advocated the building of Warm Springs Dam projected to
yield 115,000 acre-feet annually.
The United States Coast and Geodetic Survey performed a
study of potential sources of water supply in the Sonoma
County area. That study indicated that approximately
one and a half million acre-feet of water exists in a
natural storage basin overlying the Santa Rosa plain within
a depth of 200 feet. This is equal to the total
flow of the Russian River in one year. Natural
recharge of this area occurs from rainfall, making it a
renewable resource of natural filtered high quality
water. The groundwater basin in the Alexander Valley
has an estimated storage capacity of 495,000 acre feet
according to the Department of Water Resources (DWR) in
1975. The Dry Creek and Middle Reach basin has been
estimated by the DWR for over one million acre feet in Dry
Creek, Healdsburg and Windsor and over 16 million feet for
the entire basin. The depth of the Middle Reach is
probably greater than that of the Alexander Valley.
A Division of Water Rights study and U.S. Geology report
#108 described the major aquifer in the Santa Rosa plain as
located at 1400 feet. A model by the DWR states that
the aquifer is under pressure and will push water to within
200 feet of the surface for pumping. The Merced
formation of soil comprising most of the Sebastopol sandy
loams folds under the Santa Rosa plains to form this aquifer
at 1400 feet. The Agency could recharge the aquifer in
winter by ponding along the Cotati Intertie using the 50%
unused capacity of the Russian River in winter. The
injection system could take advantage of high percolation
rates in Merced soil similar to the system used in the Santa
Clara Valley where 100,000 acre feet of water is recharged
by percolation every year. Recent studies by the SCWA
indicate that aquifer injection in the Rohnert Park area
resulted in influence of sulphur compounds. Rohnert
Park, reliant on groundwater supply, chose to insure against
overdraft by contracting for one million gallons per day
(MGD) from the SCWA Aqueduct System.
Another area of historical and geographic record in the SCWA
assessment of groundwater began in 1967 when the Board of
Supervisors directed then head, Gordon Miller to try to
locate groundwater resources for the city of
Occidental. The project was turned over to two staff
engineers who didn't make correct identification of the
rocks at their chosen site of test well drilling.
Their well only produced 380 gallons per day while the
average person uses about 150 gallons per day. The
unfortunate result from this one test was the agency
contention per local area geologist, Eugene Boudreau, that
they concluded there is no water in the ground and so the
resultant solution was to build a pipeline to bring in
Russian River water.
In Gene Boudreau's book, Many Splendored
Things, the issue was raised that the Department of
Hydrology and Water Resources of the University of Arizona
analyzed the Corps Environmental Impact Statement on Warm
Springs Dam proposal and published in 1976 a statement that
the assessment for the Dam was incomplete without an
assessment of regional water demands and supplies with the
present and future use of ground water. Furthermore
they stated that the EIS alternatives failed to consider
ground water and there was no description of the aquifers
nor estimates of economic or cost comparisons.
Boudreau further noted that during the 1976-77 drought, all
towns in the county that relied on surface water had to be
rationed and towns reliant on ground water did not have any
rationing. During the time of that drought, due to
decrease water supplies, the SCWA drilled three wells in the
Santa Rosa plain and they produced at a rate of 1,200
gallons per minute. He concluded that for a cost of half a
million the wells could have produced 12, 000 acre-feet per
year while the ultimate level of Warm Springs Dam (due to
siltation) could produce 95,000 acre-feet for a cost of $230
million. In 1995, debt payment on Warm Springs began.
Boudreau asks that the County declare its Warm Springs
contract with the Corps be declared null and void since it
was fraudulently promoted by the Corps, the SCWA and the
California Department of Water Resources, and asks for our
taxpayers money back.
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