Summary Report ‎(Working Draft)‎ Modeling of Reservoir Management Strategies for Lakes Powell and Mead December 2005

• Description: Summary Report ‎(Working Draft)‎ Modeling of Reservoir Management Strategies for Lakes Powell and Mead December 2005
• State: CO
• Title: Summary Report ‎(Working Draft)‎ Modeling of Reservoir Management Strategies for Lakes Powell and Mead December 2005
• Water Supply Pro - Doc Type: Meeting

Modeling Results for
Colorado River Basin States' Modeling of
Colorado River and Reservoir Management Strategies
4.2.2 Probability of Being below a Key Elevation
50%
45%
40%
e 35%
m
v
c 30%
L
0 25%
w
0
20%
A
a
0
a 15%
10%
5%
0%
2005
Figure 4 -7
Probability of Lake Mead Elevation Below 1050
-9- Normal - Step Short Original
--A-Step Short Original
--Step Short revt
- e-Step Short rev2
--)E -Step Short rev3
2010 2015 2020 2025
Calendar Year
Figure 4 -7 shows the probability that Mead drops below 1050 ft is decreased
under the strategies that start shortages at 1100 ft compared to the Step Shortage
Original. A less significant difference in the probability is observed between Step
Shortage rev 1, rev2 and rev3.
4.2.3 Summary of Findings
Based on the Step Shortage revisions that were tested, a key finding is that Mead
is more sensitive to the elevation at which a shortage starts rather than the pattern
of shortage.
4.3 Extending the Interim Surplus Guidelines (ISG)
In addition to the sensitivity analyses for the Hybrid and Step Shortage strategies,
two other sensitivity analyses were performed that revealed significant findings.
The first analysis involved extending the Interim Surplus Guidelines from 2016
through 2025, with all other parameters remaining unchanged.
Powell was operated according to the Hybrid Original strategy. Mead's shortage
strategy was Step Shortage Original.
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