WSPP00139

• File Number: 8200.300.40.A
• Description: Colorado River Basin-Colorado River Basin Legislation/Law-Compacts-Colorado River Compact
• State: CO
• Basin: Colorado Mainstem
• Water Division: 5
• Date: 2/1/1981
• Title: Colorado River Compact-Synopsis of Major Documents-Colorado Water-Key to Tomorrows Quality of Life
• Water Supply Pro - Doc Type: Publication

.... '; i- <,

CO~FINTOP

Location
South St, Vraln, approximately 1.5 miles west of Lyons,
Colorado.

Sponsors:

St. Vraln & Left Hand Water Conservancy Dlstrlctand City
of Longmont.

Primary Purpose of the Project

Agricultural, municipal and Industrial water supply,
hydropower.

Secondary Benefits:

Flood control, recreation, minimum stream ilows, water
management to meet goals of PL 92-500.

History and Background:

The Coffintop and Geer Canyon Reservoir sites were
identified by the Bureau of Reclamation in a 1967 Recon-
naissance Study as two of several potential dam sites
along the Front Range.

In 1969, the City of Longmont finished construction of
Butlonrock Dam (Price ReserVoir) and determined that
any future reservoirs to be built in the St. Vraln or Left
Hand Basins should be a joint project among all the
citizens of the Basins rather than a single municipality.
The reasoning for this approach is that reservoirs con-
structed for municipal storage only are restricted with
respect to recreation, flood control potential and other
uses. Therefore, the City actively worked with the ditch
companies In forming the St. Vraln & Left Hand Water
Conservancy District. The Conservancy District
represents the Interests of all water users within the
basins, Including production of agricultural crops,
municipal water service. industrial water na'ads. stream
fishing, electrical power requirements and other such
general needs as flood control, Improving water quality
and. recreation.

With the formation of the District, the Board of Directors

adopted the following goals and objectives: 1) Protection
of existing decrees in the Basins; 2) Provide additional
water storage; 3) Modification of Irrigation systems to
proVide better management and higher efficiency; 4} Meet
water quality standards without negatively affecting water
users.

After working nine years to develop the overall water
management plan, it was determined that the needs of all
basin water users as outlined above can be met by the
construction of Coffintop Reservoir and Geer Canyon
Reservoir.

Physical Facts and Figures:
Height, length and type of dam: Height - 325 ft. Length
- 2000 ft.; Type - rock-earth.liII, narrow core.
Storage capacity (A.F.) of reservoir: 84,000 acre-feet.
Shoreline and surface area: Shoreline approximately 7
miles: surface area approximately 450 acres.
Average annual power generation: 150 megawatt daily;
51,000 megawatt annuaily .
PopUlation to be served: up to 132,000 people
I rrlgated acres to be served: 80,000 acres
Estimated cost: $70,000,000
. Construction scheduie: Begin construction 1985' Com-
plete construction 1990 '

Proposed Sources of Funding:
To be determined.

For Further Information Contact:

James A. Cinea; Executive Director
St. Vraln & Left Hand Water Conservancy District
Burger Building, 500 Coffman Street, Suite 107,
Longmont, CO 80501
772-4060

GEER CANYON

Location:

At mouth of Left Hand Creek about 5 miles north of
Boulder, Col~~ado, and .5 miles west of \-1.5. Highway 36.
,Y
Sponsors;
",.,\~~.
St. Vraln".8.left Hand Water Conservancy District and City
of Longmont.

Primary Purpose of the Project

Agricultural, municipal and industrial water supply.

Secondary Benefits:

Flood control, recreation, water management to meet
goals of P. 92-500.

History and Background:

The COfflntop and Geer Canyon Reservoir sites were

identified by the Bureau of Reclamation in a 1967 Recon-
naissance Study as two of several potential dam sites
along the Front Range.

In 1969, the City of Longmont finished construction of
Butlonrock Dam (Price Reservoir) and determined that
any future reservoirs to be built In the St. Vraln or Left
Hand Basins should be a joint project among ali the
citizens of the Basins rather .than a single municipality. !
The reasoning for this approach Is that reservoirs con-'
structed for municipal storage only are restricted with
respect to recreation, flood control potential and other
uses. Therefore, the City actively worked with the ditch
companies In forming the 51. Vraln & Left Hand Water
Conservancy District. The Conservancy District
represents the interests of all water users within the
basins, inciuding production of agricultural croPs,

(Continued on next page)

16