Draft EIS_072312.pdf - Middle Fork American River Project ...

20120723-4002 FERC PDF (Unofficial) 07/23/2012
a
The existing license requirement specifies storage volume in three categories of water
year types based on forecast inflow to Folsom reservoir. Where water year types in
the existing license overlap water year types used in the proposed measures, both of
the applicable elevations are provided. Elevations provided for no action correspond
to volumes listed in PCWA’s instream flow requirement measure.
b
Minimum pool requirements end on Labor Day.
c Minimum pool requirements begin on the day after Labor Day.
d Minimum pool requirements end on September 15.
e
Minimum pool requirements end on September 1.
f
Minimum pool requirements begin on September 16.
g Minimum pool requirements begin on September 2.
Our Analysis
As compared to existing operations, the minimum pools proposed by PCWA
would:
• result in higher minimum summer water surface elevations in French Meadows
reservoir during wet and above normal water year types;
• result in lower winter minimum water surface elevations in French Meadows
reservoir during wet and above normal water year types (enhance capacity to
accommodate spring runoff);
• result in higher winter minimum water surface elevations in French Meadows
reservoir during critical water year types;
• result in higher minimum summer water surface elevations in Hell Hole
reservoir during wet, above normal, below normal, and critical water year
types;
• result in higher winter minimum water surface elevations in Hell Hole
reservoir during critical water year types; and
• implement the summer/winter minimum pool elevation immediately after
Labor Day instead of at the end of September.
The Forest Service condition would provide these same circumstances and also
result in in higher minimum water surface elevations in French Meadows reservoir during
below normal and critical water year types as compared to the existing license conditions.
Whereas PCWA’s proposal for minimum reservoir elevations transitions from summer to
fall on Labor Day, the Forest Service condition transitions at different times based on
water year type.
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