Clifton Court
Forebay Diversions/8500 cfs
State Water Project Operations at Clifton Court Forebay
and Harvey O. Banks Pumping Plant
The discussion below provides a background
on the SWP and CVP operations, including a description
of how the SWP’s CCF and SWP Banks currently work,
as well as annual, weekly, and daily operations, and
information on DWR’s Corps permit and joint point
of diversion (JPOD).
Annual Operations Planning
DWR and Reclamation estimate the amount of
water that will be provided to their respective contractors
each year, existing and forecasted, based on rainfall,
existing storage, available data export and conveyance
capacity, and beginning snowpack measurements of each
year. This amount is usually a percentage of the contractors’
full contractual amount. As the year progresses and
forecasted data is replaced with actual data, those
allocations may be revised.
Weekly Operations Planning
To plan weekly project operations, Bay-Delta
tides are estimated using the National Oceanic and Atmospheric
Administration’s (NOAA’s) forecasted tides
and regression relationships with flow and salinity
at various Delta locations. Based on the best estimates
of weather conditions and past experience, a target
Delta outflow is determined that is expected to meet
the controlling water quality standard as well as other
standards. DWR and Reclamation coordinate reservoir
releases to meet the target outflows (California Department
of Water Resources and Bureau of Reclamation 1996a).
Daily Operations
During actual daily project operations, data
are transmitted hourly to DWR and Reclamation hydrometeorological
systems in their water management control centers in
Sacramento. These data consist of river flows, tides,
salinity, and wind speed/direction at various Delta
locations. If the data indicate a significant deviation
from the planned conditions, one or more of the three
following operational changes can be implemented: (1)
adjust project reservoir releases; (2) adjust Delta
export levels; and (3) close or open the Delta Cross
Channel gates. Reservoir releases are most effective
for meeting Sacramento River salinity criteria (most
frequently at Emmaton) or Delta outflow criteria. San
Joaquin River salinity criteria (most frequently at
Jersey Point) are most effectively met by adjusting
the amount of export pumping.
Rivers and Harbors Act
CCF and SWP Banks operate under a nationwide permit
issued by the Corps under Section 10 of the Rivers and
Harbors Act for construction and operation of facilities
prior to 1968. Since 1968, four pumps were added to
SWP Banks. DWR subsequently requested that the Corps
provide a new permit under the Rivers and Harbors Act.
In 1981, in Public Notice 5820A, Amended (Public Notice),
dated October 13, 1981, the Corps determined that
operation of the expanded facility such that future
diversions into the forebay do not exceed the historical
maximum one-day and three-day diversion rates would
have no increased effect on navigable capacity of the
Delta waterways. Therefore, no additional permit will
be required under Section 10 of the River and Harbor
Act of 1899 provided that the historical maximum diversion
rates are not exceeded.
The Public Notice notes that those
maximum diversion rates into CCF are 13,870 acre-feet
(af) daily (and 13,250 acre-feet over a 3-day average).
DWR also presented the Corps with plans to increase
diversions by one-third of the San Joaquin River flow
at Vernalis during the period from mid-December to mid-March,
provided that flows at Vernalis exceed 1,000 cfs. The
Corps’ Public Notice states that
analysis of this proposed operation
indicated that there would be no additional reduction
in water levels at Clifton Court Ferry because any increased
drawdown would be off-set by higher stages caused by
increased San Joaquin River flows.
The Corps concluded that “diverting
one-third of the flow at Vernalis during the timeframe
proposed would have no effect on navigable capacity,
and no Section 10 permit is required for this operation.”
Under all the SDIP proposed operational scenarios, the
maximum diversion capacity would be higher than the
currently permitted 6,680 cfs. Therefore, increased
diversions would require a new Rivers and Harbors Act
Section 10 permit from the Corps.
Joint Point of Diversion
The CVP and SWP historically have shared Delta export
pumping facilities to assist with project deliveries
and to aid each project during times of facility outages.
The sharing of these facilities is referred to as JPOD.
In 1978, DWR agreed to, and the State Water Board permitted,
the CVP to use the SWP Banks facility to export up to
195,000 acre-feet annually to replace pumping capacity
lost at the CVP Tracy facility because of striped bass
pumping restrictions in D-1485. In 1986, Reclamation
and DWR formally agreed that “either party may
make use of its facilities available to the other party
for pumping and conveyance of water by written agreement”
and that the SWP would pump CVP water to make up for
striped bass protection measures (California Department
of Water Resources 2003a). Per D-1641, use of JPOD is
subject to an operations plan that protects fish and
wildlife and other legal users of water. Thus, such
joint point pumping essentially occurs only under conditions
acceptable to NOAA Fisheries, DFG, USFWS, and the State
Water Board, among other considerations. Although JPOD
would continue to be implemented as it is currently,
the operational scenarios under SDIP provide additional
JPOD opportunities in the winter and summer periods.
However, it could not be assumed that JPOD could provide
the CVP with increased certainty and allow for increased
water allocations to CVP contractors south of the Delta
earlier in the year.
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