WSPC12493 ‎(2)‎

• File Number: 8220.101.10
• Description: Colorado River Water Projects - Glen Canyon Dam-Lake Powell - Adaptive Management
• State: CO
• Basin: Colorado Mainstem
• Date: 4/1/1996
• Author: DOI-BOR
• Title: CRSSez - Annual Colorado River System Simulation Model - Overview-Users Manual - Update of 04-01-96 - With Revisions of 09-01-96 - 04-01-96
• Water Supply Pro - Doc Type: Report/Study

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OJJ3:5

Basin use, crit12 is the 12-year critical runoff volume, evap is
12 times the average of powells current year evap and minimum
evap plus the Upper reservoirs current year evap, an~ uc is the
Upper reservoir current content. other critical periods and
volumes may be set in the user interface. Mead storage is
adjusted for any banked water, including banked water in
shoreline storage, before comparing with Powell.

Powell's objective release is increased by half the difference in
storage between Powell and Mead up to the 602a storage
requirement. Powell balance is rerun starting at step 10.

Mass Balance:

step 12. Powell, Mead, and Upper Reservoir storage change is
checked against inflows and outflows. Lower Basin use is checked
against sum of final surplused and shorted uses. Mead release is
checked against final uses, gains, and Mexican delivery. The
user will be notified of the amount of the unbalance of any of
these checks, and the run is aborted.

Glen and Hoover Energy:

step 13. Glen Energy is computed as -24791 + 6.738 * pavgelev +
0.46065 * glenout where glenout is total Glen release and
pavgelev is average Powell elevation for the year. If pavgelev
is less than 3460 feet then Glen energy is zero. Glen energy is
limited to the capacity of 8500 gwh. Hoover energy is computed as
-8200 + 6.3212 * mavgelev + 0.53944 * hoovout, where hoovout is
Hoover release and mavgelev is Mead average elevation for the
year. If mavgelev is less than 1050 feet then Hoover energy is
zero. Hoover energy is limited to the capacity of 9960 gwh.
These multiple regression formulas agree very closely with the
theoretical assumptions in the CRSS model for reduced efficiency
at lower heads.

Bank Evaporation and Spill:

14) Remove water banking evaporation and spill from bank
accounts.

Reservoir Sedimentation:

step 15. Annual Powell and Mead adjustments to their capacity
table are based on a polynomial regression of capacity change for
each elevation in the capacity table over a 57 year run of CRSS.
The annual sedimentation rate for each capacity in the Powell
table is computed as 45981.39-39.69507*elv+1.139328E-02*elv*elv-
1.086971E-06*elv*elv*elv. The annual sedimentation rate for each
capacity in the Mead table is computed as -296.7294 +
0.5035896*elv + 1.930599E-04*elv*elv. The annual sedimentation
rate of the Upper Reservoir is 5.091 kaf/yr.

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