C150002 Application

• Contract/PO #: C150002
• Contractor Name: Grand Valley Water Users' Association
• Contract Type: Grant
• Water District: 0
• Bill Number: SB 97-8
• Loan Projects - Doc Type: Application

3

CWCB Construction Fund Grant Application
Grand Valley Water Management Project

The power plant consists of two units with one or both units operated depending on the available
supply of water. After going through the power plant, the water is normally returned to the 15-
Mile Reach.

At maximum irrigation-season diversion and usage levels, OMID can demand up to 460 ft?ls for
irrigation/pumping (includes 10ft? Is delivered to the Vinelands). The sum of all the water rights
which could be diverted at the Grand Valley Diversion Dam is approximately 1,710 ft?ls, but due
to a canal capacity constraint between the diversion dam and Tunnel No.3, only about 1,620 ft3/s
can be diverted. This restriction limits the Grand Valley Power Plant to 310 ft3/s during periods
of peak irrigation demand. At less than full irrigation demand, up to 400 ft3/s can be used to
generate hydroelectric power. The 90 ft3 I s shortage (400 - 310) is due to the capacity constraint.
Without this constraint, the Grand Valley Power Plant would receive 400 ft3/s throughout the
irrigation season assuming water supplies were available. Consequently, if irrigation demand in
the Garfield Gravity Division is reduced, up to 90 ft3/s of conserved water could be used for
power generation.

The Orchard Mesa Division facilities also include a check structure and by-pass channel located in
the tailrace of the pumping and power plants and a supplemental pumping plant downstream on
the Colorado River. The check structure and by-pass channel provide the means to operate an
exchange of water to maximize the use of available water supplies during drought periods. Under
this exchange, water destined to the senior Grand Valley Irrigation Company water right is used
for pumping and power generation purposes and returned to the Colorado River upstream of the
Grand Valley Irrigation Company diversion dam.

Other Irrigation Systems: Two irrigation districts, Palisade and Mesa County Irrigation Districts,
also receive water from the Government HigWine Canal through a carriage contract. The
operation of these systems is not included in the on-going Grand V alley Water Management
Study.

The Garfield Gravity Division: Through the Garfield Gravity Division, GVWUA delivers water
to approximately 1,400 water users. The GVWUA system serves approximately 23,340 of the
70,000 irrigated acres in the Grand Valley. The Gravity Division's Government Highline Canal
delivers water to 74 laterals totaling about 160 mi. After completion of the Salinity Control
Program, 30 mi. of the 50 mi. of canal will be lined and nearly all of the laterals are scheduled to
be placed in pipe.

The Government HigWine Canal is divided into four sections. Beginning at the outlet of Tunnel
No.3 and moving west, the sections are; the East End Government HigWine Canal, Middle
Government HigWine Canal, Stage One, and West End Government HigWine Canal. All of these
canal reaches, except the Middle Government HigWine Canal and the first 2 miles of the East End,