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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banks and then from the Other bank. Surplus if caused by banking
first comes from users bank before system water and other bank.
Evaporation is removed at end of year from all banks.

For a Middle Bank, any excess to Mexico caused by the water in a
Top Bank is transferred to the Middle Bank. The Middle Bank is
first used before the Top Bank. If Lake Mead drops to within 20
feet of the shortage trigger before spilling, then the Middle
Bank is zeroed out and payback of the bank is made by reduction
in use by 10% per year. Excess to Mexico reduces the Middle Bank
debt by a like amount. Evaporation is not taken from the Middle
Bank.

The Groundwater Bank puts the banked water off system and does
not effect reservoir operations, nor is it lost during a spill.
The Groundwater Bank is assumed to be on the CAP and diversions
are reduced and groundwater used in lieu of system water to
permit use of banked water by the owner of the bank. The CAP
value on the main reservoir output sheet shows total water used
by CAP, both system and groundwater. The CAPGW value on the
banking sheet shows actual diversions from Lake Havasu on the
CAP.

Water in the above banks is used by CAP only in times of
shortage. SNWS uses banked water as necessary to meet their
surplus schedule. MWD uses banked water based on the SACRO
trigger index.

Other banking is done by setting a maximum Other bank greater
than zero and selecting variable Other Ag use. Other banking is
not a bank as the fallow bank is but an over draft permit. Use
above the normal Other schedule is a debit that must be paid back
by a 10% reduction in use when Lake Mead is within 20 feet of the
shortage trigger. Excess to Mexico reduces the Other debit by
the amount excessed should that occur before payback is required.

Lower Basin Shortage:

Step 9. There are three shortage strategies that may be selected
from the EZ user interface.

Elev Short Protection: This shortage
use/draw down curve for protection at
not going below the given elevation.
described in Appendix B.

Mead Short at Elev: If the beginning Mead elevation adjusted for
banked water is below the shortage trigger elevation read from
the user interface, default is 1120 ft, then a shortage
determination is made. CAP is reduced to the delivery read from
the user interface, default delivery is 1000 kaf. SNWS is
reduced by 4% of the amount that CAP was reduced from its

method is based on a
the given probability of
This shortage method is

9