WSP03901

• File Number: 8446
• Description: Cache La Poudre Platte Project
• State: CO
• Basin: South Platte
• Water Division: 1
• Date: 11/1/1962
• Author: BOR, DoI
• Title: Reconnaissance Report, cache La Poudre Unit, Colorado Peak Division, Missouri
• Water Supply Pro - Doc Type: Report/Study

.~

Attainment of these objectives wi1.l necessitate Federal
construction of water storage and power facilities and actions by
local interests such as transferring of water rights, abandonment
of some existing reservoirs, consolidation of certain other
existing reservoirs, and other actions 1.eading to the conservation
and better use of water,

The planned power function is unique in that it would be
operated principa1.1y for peaking. The p1.an would also be adaptable
for pump storage power operations.

The principal Federa1. features wou1.d be two storage dams and
reservoirs, two powerp1.ants, one power afterbay, one power forebay,
one diversion dam, condUits, transmission lines, and substations.

.

Water regu1.ated in the upstream Idy1.wilde Reservoir (180,000
acre-:t'eet) wou1.d be discharged through the Idy1.wi1.de Powerp1.ant
(24,000 ki1.owatts) and be reregulated in the Kinnikinick Afterbay
(1.,000 acre-feet). About 8 mi1.es downstream the Rustic Diversion
J:8m wou1.d divert water via the 11. 5-mile Elkhorn Conduit to the
Cache 1.a Poudre Forebay (5,400 acre-:t'eet). Re1.eases from the
forebay wou1.d enter a 5,000-foot pressure tunne1. to the Cache la
Poudre Powerp1.ant (250,000 kilowatts) which would discharge into
the terminal Grey Mountain Reservoir (220,000 acre-feet). This
reservoir would a1.so have capacity for storage and reregu1.ation
of municipal and industrial water and for transferred p1.ains
reservoirs.

The estimated tota1. project cost is $l1.l,1.08,OOO, and the
annua1. operation, maintenance and rep1.acement expenses 4'655,600.
These costs have been al1.ocated as fo1.1ows:

Power
Municipal and Industria1. water
Irrigation
F1.ood contro1.
Fish and wild1.ife
Recreation

Project Costs

$ 88,342,000
6,244,000
5,1.97,000
192,000
5,466,000
5,667,000

$1.11., 108,000

Annual
OM&R Costs

Tota1.

4'646 , 400
2,600
2,100
100
2,100
2,300

4'655,600

Approximately 91. percent of the project costs are reimburs-
able and their amortization is attainab1.e within a 50-year period
after comp1.etion.

The benefit cost ratio is 1..45 to 1. :t'or the project. Idylwi1.de
J:8m and Reservoir, if constructed first, cou1.d be used initia1.1y for
some functions such as irrigation, recreation, municipal and industria1.

.

2

Revised 6/26/63