Quarterly Water Supply Strategy and
Budget Report
California American Water, Water
Distribution System: January – March 2006
December
12, 2005
1. Management
Objectives
The
District desires to maximize the long-term production potential and protect the
environmental quality of the Carmel River and Seaside Ground Water Basins. In addition, the District desires to maximize
the amount of water that can be diverted from the Carmel River Basin and
injected into the Seaside Ground Water Basin while complying with the instream
flow requirements recommended by the National Marine Fisheries Service (NMFS)
to protect steelhead, red-legged frogs and other aquatic resources in the Carmel
River. To accomplish these goals, a
water supply strategy and budget for production within the California American
Water (Cal-Am) water distribution system is reviewed quarterly to determine the
optimal strategy for operations, given the current hydrologic and system
conditions.
2. Quarterly
Water Supply Strategy: January – March 2006
On
December 1, 2005, staff from the District, Cal-Am, National Marine Fisheries
Service (NOAA Fisheries) discussed the proposed water supply strategy and
related topics for the remainder of December 2005 and the January – March 2006
period. In addition, the California
Department of Fish and Game reviewed a draft of the proposed water budget and
operations schedule. As of November 30,
2005, Los Padres Reservoir was drawn down to elevation 1,009.40 feet with 502
AF of storage, the Carmel River unimpaired inflow at San Clemente Dam was
approximately 11 cubic feet per second (cfs), and the drying riverfront was
located at Cal-Am’s San Carlos Well at River Mile 3.9 (RM 3.9).
Based
on the higher than projected runoff that has occurred since the beginning of WY
2006 and an expectation of additional rainfall and runoff in December 2005, the
group agreed to set the projected unimpaired monthly flows at San Clemente Dam
for the January through March 2006 to the low-end of the normal range, which is
equivalent to flows that have been exceeded 62.5% of the time during the
simulated reconstructed historical record (1902-2005). In addition, staff reviewed the inflow to
date through November 30, 2005, and decided to use inflow levels at the 62.5%
exceedance level for the remainder of December 2005. Accordingly, Table 1 shows a monthly breakdown of
the diversion and release schedule based on the assumption that unimpaired
inflows at San Clemente Dam will equal 1,536 Acre-Feet (AF) in December, 4,559
AF in January, 6,057 AF in February and 7,359 AF in March. Table 1 lists actual or expected
inflows, outflows, and storage volumes at Los Padres and San Clemente
Reservoirs for the October 2005 through March 2006 period. For this analysis, it was assumed that Cal-Am
would not directly divert water from San Clemente Reservoir to the Carmel
Valley Filter Plant, consistent with the 4d rules adopted by the NMFS to
protect steelhead, State Water Resources Control Board Water Order WRO
2002-0002 and the Conservation Agreement between NMFS and Cal-Am, which governs
diversions during the low-flow period.[1]
During December 2005 and January – March 2006, actual inflows may be
significantly more or less than projected. If so, the group will reconvene and
adjust the operations accordingly.
For
the Seaside Basin, it was agreed that in the January-March 2006 quarter, Cal-Am
will produce a total of 184 AF, with all of the production in January 2006.
These levels will help to conserve aquatic habitats in the Carmel River and
constrain annual withdrawals from the Seaside Basin, and are consistent with a
goal of reducing Cal-Am’s annual production in the Seaside Basin by 6 %, from
the 1995-2005 average of 3,748 AF/yr to 3,518 AF/yr. In anticipation of
re-issuance of the District’s temporary water appropriations permit to divert
Carmel River water and inject it into the Seaside Basin, it is assumed that a
total of 327 AF will be diverted and injected during the January – March 2006
period.
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12/8/2005 5:22 PM
[1]
The
low-flow period is defined as times when streamflow in the Carmel River at the
MPWMD gage at Don Juan Bridge is less than 20 cfs for five consecutive days,
which occurred on July 20, 2005. Based
on projected inflows, streamflow is expected to be less than the 20 cfs
threshold in October and November. In December, inflows may increase above the
threshold, but the timing of this event and the continuance of the 2005 San
Clemente Interim Drawdown Project into December may preclude any significant
change in operations.