9584

• UCREFRP Catalog Number: 9584
• Author: U.S. Fish and Wildlife Service.
• Title: Draft- Aspinall Unit Operations Study.
• USFW Year: 1988.
• USFW - Doc Type: \
• Copyright Material: NO

Hydross Simulation of the Aspinall Unit
Having developed the basic network, table, and flow information
presented above, the operation of the three reservoirs which
comprise the Unit were modeled based upon a the basic operational
criteria described in the Concervancy document and information
obtained from the Bureau. The basis of the operation is reservoir
target contents for each month for each reservoir in the Unit.
Target reservoir contents were then used to drive the month to
month operation in conjunction with water right requirements of
downstream users. Targets for Blue Mesa Reservoir vary by month,
while Morrow Point and Crystal are set to maintain contents equal
to the maximum content through the year.
Using these reservoir targets and reservoir delivery requirements
as a starting point, simulation of the Unit was accomplished by
building upon known operational characteristics and using a trial
and error methodology. The first simulation, Trial 1, consisted
of using a monthly release of 200 cfs for the IFR below Crystal
with a full diversion requirement for the Gunnison Tunnel. The
model was operated for 1982 and the results were reviewed by Randy
Peterson of the Bureau. Randy pointed out several technical
problems, but found the reservoir operation to be reasonable. The
network and tables used for the trials are attached.
Trial 2 consisted of implementing the changes Randy Peterson
suggested. The changes produced the desired results, and
confirmed that reservoir operation was working properly.
Trial 3 consisted of extending the period of operation to include
the period 1972 to 1982. The result of this operation was
successful in terms of reservoir operation, which again appeared
reasonable. But when the flows near Grand Junction were compared
with gage flows, wide discrepancies were noted.
Trial 4 used the gaged inflow as described above. The results of
this operation were reviewed and were found to be considerably in
excess of the gage near Grand Junction.
Trial 5 consisted of operating the model with the consumptive use
on the two Gunnison Tunnel diversions set to 100 percent
consumptive use because they would be included in the gage flows
for the Uncompahgre at Delta. The results of this operation were
good, with the exception of the period when the unit was actually
in operation. This was caused by reservoir targets not matching
the actual operation of the reservoirs for the 1968 to 1982
period.
NOTE: Trials 1 through 5 were the composites of many different
operations and represent only the most significant and meaningful
changes in operation.
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