THE COLLEGIATE RANGE PROJECT

JULY 1986 I. Introduction The Basin has long been considered one of the finest water resources in the State of . To date, development of this resource has been undertaken by the United States government. The primary purposes of this development have been to regulate streamflow for:

1) hydropower generation for Storage Project participants and

2) diversion to the Uncompahgre River Basin for agricultural uses.

The City of Aurora has applied for conditional water rights on tributaries to the Gunnison River for a water supply development entitled the "Collegiate Range Project."

The plans for this project were initially prepared by Marvin J. Greer, the general partner for Sierra Madre Lode, Ltd. Mr. Greer is a retired engineer formerly with the U.S. Bureau of Reclamation. The City of Aurora has reviewed these plans as well as other Gunnison River water supply reports.

1) "Water and Related Land Resources, Gunnison River Basin" - Colorado; Colorado Water Conservation Board, U. S. Department of Agriculture; 1962, 2) "The Collegiate Ran~~ Project - A Water Supply Development''; Sierra Madre Lode, Ltd.; Undated,

3) "Water Rights Evaluation in the Gunnison River Basin, Collegiate Range Project", The David E. Fleming Company; 1985.

The latter report was commissioned by the City of Aurora.

The Collegiate Range Project is proposed as a transmountain water diversion project. Essentially, water is to be diverted from the Taylor River and one of its tributaries, Texas Creek, and stored in Pieplant Reservoir. Water would be conveyed via the Taylor Platte aqueduct from Pieplant Reservoir to the South Platte River Basin. Replacement for any out-of-priority div~rsions would be made from releases from Almont Reservoir. (See Figure 1)

The projected average annual yield of the project is 73,100 acre-feet with a maximum yield of 108,500 acre-feet. Project costs are estimated to be in the range of $250,000,000 to $320,000,000 or $3,500 to $4,500 per acre-foot.

The Collegiate Range project will be a part of the City of Aurora's long-range water planning process. The need for this Project is projected to occur shortly after the turn of the century. As such, this project is not planned as a replacement or alternative to the proposed Two Forks Project or Homestake II.

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COLLEGIATE RANGE PROJECT LOCATION MAP Fig. 1

-j- II. River Basin Descriptions

A. The Gunnison River

The Gunnison River Basin encompasses an area of 8,020 square miles, or about eight percent of the area of the State of Colorado. Elevations vary from 4,500 feet to 14,300 feet above sea level. Average annual precipitation ranges from less than 10 to more than 40 inches. Average annual frost-free period in the agricultural areas varies from 70 to 190 days. Settlement of the Basin began in 1873, with mining being the principal industry. Livestock raising and growing of crops followed the decline of the mining industry. Seventy-one percent of the land in the Gunnison Basin is in federal ownership, 28 percent is privately owned, and approximately one percent is owned by the State of Colorado. Approximately five percent of the lands of the Basin are used for crop production with the remaining 95 percent being used for grazing and timber production watershed and recreation purposes. 1

The Gunnison River is formed by the confluence of the Taylor and the East Rivers at the town of Almont, eleven miles northeast of the City of Gunnison. The river flows southwesterly through this town, which is the county seat of Gunnison County. Flowing another eight miles, the river turns more westerly and enters Blue Mesa Reservoir which when full, inundates fifteen miles of

1. From 11 Water and Related Land Resources, Gunnison River Basin-Colorado. 11

-4- t~e streambed. It then flows through Morrow Point Reservoir and turninq northwesterly flows through Crystal Reservoir and enters the Black Canyon of the Gunnison, where it is entrenched a mile below the adjacent mesas. Below the canyon, near the town of Delta, the North Fork of the Gunnison enters the river. Turning westerly for a few miles and then again northwesterly the Gunnison River flows another forty miles to enter the Colorado River, near the City of Grand Junction, Colorado. The seventy-four year average flow at this confluence (1982 records) is 1 ,826,000 acre-feet per year for the Gunnison River. The Collegiate Range Project proposes to divert 7,000 acre-feet of this amount annually (less than 4 percent of the flow).

B. The East and Taylor Rivers

The project is principally concerned with the East and Taylor Rivers above their confluence at Almont. The seventy-two year average flow of the Taylor River at this village is 241 ,300 acre-feet annually (1982 records). The flow of the at this location is 272,700 acre-feet annually, a sixty ye1r average (1982 records). Aside from diversions for local in-valley irrigation of 7,400 acres from the East River and 360 acres from the Taylor River, there is just one large water development on the two streams. This is Taylor Park Reservoir which can store 111 ,260 acre-feet of water and has a water right for this amount. The water is used by the Uncompahgre

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Valley Wa~er Users Association. The annual flow at the reservoir,which was completed about 1938, is 136,120 acre­ feet after reservoir evaporation. The Taylor Park Reservoir when full covers an area of about 2,240 acres.

III. Project Features

The project will consist of the following major structures:

l) Almont Reservoir 2) Pieplant Reservoir

3) Taylor Platte Aqueduct

4) Texas Creek Pipeline 5) Texas Creek Diversion Channel

6) Taylor Lakeshore Pump and Relift Pump

Almont Reservoir is designed to store 92,000 acre-feet of water which amount is claimed to exchange for Taylor River water at Pieplant Reservoir and for a permanent recreation pool covering about 375 acres. Water in the Taylor River at the Pieplant Reservoir site is presently needed to supply the Uncompahgre Valley Water Users Association (UVWUA), at Taylor Park Reservoir. Water releases from Almont Reservoir will meet 70,000 acre-feet of the UVWUA needs, thus allowing by exchange the diversion of this amount of water from the Taylor River at the Pieplant Reservoir to the eastern slope. The Almont Dam would be 198 feet high from river bed to crest, 184 feet to the high water surface at elevation 8,244,

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thus allowing 14 feet of freeboard. The dam would be of earth and would be 1 ,775 feet in length at the crest. A spillway on the left of the dam would have a 125 foot long crest and would pass the maximum possible flood using a surcharge depth of 12.15 feet. The outlet would be on the right side of the river via a tunnel. When the reservoir is full it would have a water surface area of 1 ,300 acres. The land inundated is private, school, state and federally owned. The Roaring Judy Fish Hatchery is on the state land. The lowest part of the cemetery near Jacks Cabin would be about 4 feet above the high waterline of the reservoir.

The Pieplant Dam would be 196 feet high from streambed to crest, 182 feet from the base to the hi~h water surface at elevation 9,540. There would be 14 feet of freeboard above this elevation. While the crest of the dam is 2,800 feet long, one-half of this length is less than 75 feet high. A side crest spillway would be on the left of the dam. It would be designed for the maximum probable flood and have a 125 foot long crest and a water depth of 12.3 feet afforded by the 14 feet of freeboard. The total capacity of the reservoir is 64,500 acre-feet, the active capacity 57,700 acre-feet and the recreation pool 6,800 acre-feet. The surface area of the reservoir when full is 1 ,000 acres and is 200 acres at the top of the recreation pool.

The Taylor-Platte Aqueduct consists of two major features: Ice Mountain Tunnel and the Pine Creek - Antero Reservoir Aqueduct.

-7- The Ice Mountain Tunnel would be 17.17 miles long and have two portals. It is designed to be a concrete lined circular tunnel seven and one-half feet in diameter. The capacity is 150 cfs with minimum water surface in Pieplant Reservoir. When the Pieplant Reservoir is full, the tunnel, under pressure, would carry 285 cfs. The grade of the tunnel is 0.447 feet per 1 ,000 feet or 2.36 feet per mile. Both portals are well outside the Collegiate Peaks wilderness area.

The Pine Creek-Antero Reservoir aqueduct is 26 miles long. Beginning at the east portal of Ice Mountain Tunnel 8,900 feet of 5 ft. diameter precast concrete pipe conducts the water to the Arkansas River siphon. The center section of this siphon consists of 3,500 feet of concrete embedded, 4 ft. diameter, steel pipe. It would cross the river fifteen feet below the streambed, where it would be under 740 feet of head (320 lbs. per square inch pressure). Low pressure (up to 70 feet of head) cast in place concrete pipe 5 ft. in diameter forms the ends of the siphon, l ,700 feet on the upstream end and 300 feet on the downstream end. The next section of the aqueduct consisting of 9.7 miles of 5 ft. diameter precast concrete pipe, 1.4 miles of 5 ft. diameter cast in place concrete siphon and 1.7 miles of 7.5 ft. diameter tunnel leads to the Trout Creek Pass Tunn=l. This tunnel is also 7.5 ft. in diameter and is 5.8 miles long ~ It ends in South Park at the foot of the pass. The conduit continues with 5 ft. diameter precast concrete pipe for 10,000 feet, 1.9 miles, after which it changes to 4.5 ft. diameter precast concrete pipe for 2.8 miles and ends in Antero Reservoir.

-8- The total distance from Pieplant Reservoir to Antero Reservoir is 43.1 miles made up of 24.6 miles of 7.5 ft. diameter tunnel, 13.3 miles of 5 ft. diameter precast concrete pipe, 2.8 miles of 4.5 ft. diameter precast concrete pipe, 1.7 miles of 5 ft. diameter cast in place concrete siphon and 0.7 miles of 4 ft. diameter steel pipe siphon embedded in concrete. At water surface elevation 9,246.6 and 5.8 miles from the east portal of Ice Mountain Tunnel, the conduit crosses the Aurora aqueduct above the Arkansas River Pumping Plant, east of the river.

The Texas Creek Pipeline would divert a maximum of 250 cfs from this stream and transport it to Pieplant Reservoir for further diversion via the Taylor-Platte Aqueduct.

The Texas Creek diversion channel, a minor feature, is planned to reduce the amount of water that needs to be released from Pieplant Reservoir to keep the Taylor River alive from Pieplant Dam to Taylor Park Reservoir. If it does not accomplish this purpose it is not needed. It is anticipated that material from this channel can be used in the construction of the Pieplant Dam. The channel would divert the total flow of Texas Creek at a point just above the road crossing at elevation 9,389, and conduct the water lt miles to the downstream toe of Pieplant Dam. From this point the water would flow in the Taylor River down to Taylor Park Reservoir. The channel would be constructed to simulate a streambed with varying widths and grades. The present channel of the creek downstream from the diversion would be obliterated.

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The Taylor Lakeshore Pump would be constructed on the northeast shore of Taylor Park Reservoir. This pumping plant would divert water from the reservoir and discharge it to the Texas Creek Diversion Channel. A portion of the water would be discharged to the Taylor River to satisfy minimum streamflow requirements. A relift pump located near the downstream toe of Pieplant Dam would pump water into Pieplant Reservoir.

The paved highway, 135, would have to be relocated around Almont Reservoir. The graveled road leading up the Taylor River Valley would have to be relocated around Pieplant Reservoir. This relocation would automatically serve as access to the west portal of Ice Mountain Tunnel.

The dam sites , all diversion points, and the west portal of Ice Mountain Tunnel have been surveyed and tied into section corners. Stakes have been set at these features.

IV. Project Benefits

The Collegaite Range Project would offer benefits to the City of Aurora which include: a water source of superior quality, direct flow water rights, and water storage. Should the project be managed cooperatively with the people of Gunnison County, local benefits that would accrue are:

-10- 1) An increase in jobs both immediately (for environmental studies) and in the future (for project construction),

2) Stream flow regulation benefits would include:

i) Fishery benefits ii) River recreation iii) Flood alleviation iv) Downstream power generation

3) Water storage benefits would include:

i) Drought protection ii) Lake recreation iii) Improvement of water quality by settling of suspended solids - providing more stable flow - controlled temperature releases.

The City of Aurora fully recognizes that many important local and environmental issues need to be thoroughly addressed during project planning stages. The City is corrrnitted to a continuing and meaningful dialogue with all affected interest groups. Although the water rights filing necessarily has specific project features, alternative development scenarios are expected to be studied which would maximize local benefits. The planning process for the project will continue for several years.

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