WSP00620

• File Number: 8220.100.40
• Description: CRSP
• Basin: Colorado Mainstem
• Date: 3/14/1963
• Author: USDOI
• Title: Sixth Annual Report on the Statuts of the Colorado River Storage Project
• Water Supply Pro - Doc Type: Annual Report

12

CO~ORADO RIVER STORAQE PROJECT

stllJ't significant filling durinl;( the spring runoff of 1963, Flaming
Gorge will probablr stllJ't fillmg about the same time, Navajo will
be about 1 year elliI'lier, Ourecanti is not scheduled to start storing
water until the faWof 1965.
, Sugges~ioJOls wer~ made ,that tabular forms illustrating the appli.ca-
tron of prmmple 5, l\long wtth explanatory sheets and an accompanymg
statement of criteria for operation of Lake Mead to determine Hoover
basic firm power in computing allowance for deficiency, be made a
part of the general principles and criteria by attachmcnt, W 0 fully
recognize that it is only through having this information available
that a precise understanding of the intended application of principle 5
is gained. . ,
Notwithstanding; this, however, we are not inclined to incorporate
either the tabular forms or the accompanying explanatory material
into the general llrinciples and criteria. We believe such action
would give undue stgnificance to a matter which must remaiu open to
the exercise of secretarial judgment, particularly as to the use of
forms, There is included with this memorandum, however,the
tabular forms and explanatory materials which we would intend to
use, at least initially, for the purpose of computing the Hoover basic
firm and the diminution in power generation under the formula of
principle 5,
The forms included herewith are different from those supplied at
the Boulder Oity meeting in June 1960.
One revision mac!e in the material is in the method of handling the
efficiency factor. A further review of the tentative forms supplied
at the Boulder Oity! meeting showed that in this respect they followed
the present billing process rather than the intent of principle 5, which
was to be a theoretical computation based on overall efficiency,
Our position on use of the 83 percent efficiency factor is, we believe,
well set forth in th~ January 18, 1960, memorandum and need not be
repeated here, Suffice it to say that in the original Hoover firm
energy computatiojl made for the general regulations, 83 percent
efficiency was appl(ed in satisfaction of the formula-acre-feet times
head times efficiency times 1.025 equals kilowatt-hours, It was our
intent to again apply the 83 percent efficiency factor in this manner,
The teutative forms, however, showed a netting out of service station
use, leakage and pUfllpage which is appropriate for the billing process,
but not for the theoretical computation, We do not, of course, intend
to change the actus;} billing process, Another revision made is in the
method of handling evaporation losses of the storage project reser-
voirs, For reasons explained hereinafter, such evaporation IS not now
included as a part of the theoretical streamflow of the Oolorado
River at Grand Oanyon,
Representatives rf the upper basin have expressed concern over
the contemplated inclusion of evaporation from the storage project
reservoirs as a part of theoretical streamflow used in the formula
for computing alloWance. We have given this matter considerable
attention and havel concluded that our past studies on handling of
evaporation losses have not been consistent with our handling of
stream depletions caused by the participating projects, All factors
considered and in the interest of conststency, we have concluded
that storage project reservoir evaporation should not be considered
as part of the theoretical streamflow to be used in calculating
diminution in Hoover generation.