ColoradoBasinWaterSupplyandNeedsReport

• Basin Roundtable: Colorado
• Title: Water Supply & Needs Report for the Colorado Basin
• Date: 5/1/2006
• Basin Roundtables - Doc Type: Needs Assessment Documents

Section 3
Physical Environment of the Colorado Basin

a loss of population in the Gunnison River or in the
Colorado River below the Gunnison River confluence
(U.S. Fish and Wildlife Service [USFWS] 1999).

Several regulations and operating plans have been
developed to maintain adequate water supply for the
15-Mile Reach, as discussed in Section 8.

In addition to impaired areas, threatened and endangered
species and areas of high environmental or recreational
value require special attention when evaluating water
supply projects and use patterns in the basin.

Areas in the Colorado Basin with high-quality aquatic
habitat have been awarded the Gold Medal designation.
The reaches in the Colorado Basin include:

. Blue River from Dillon Reservoir Dam downstream to
the Colorado River (34 miles)

. Gore Creek from Red Sandstone Creek downstream
to the Eagle River (4 miles)

. Colorado River from Windy Gap to Troublesome
Creek, 3 miles east of Kremmling (20 miles)

. Fryingpan River from Ruedi Reservoir Dam
downstream to the Roaring Fork River (14 miles)

. Roaring Fork River from the Crystal River
downstream to the Colorado River ( 12 miles)

Figure 3-8 shows the locations of some of the basin's key
aquatic species habitat.

Other areas of high recreational value in the basin,
including Green Mountain Reservoir, Lake Granby,
Rocky Mountain National Park, and Indian Peaks
Wilderness area, are discussed in Section 6.

3.2.10 Energy and Mineral Resources

Metal mining is an important economic activity in the
headwater areas of the Colorado Basin. Past and
present mining activities have included the extraction of
metals such as copper, gold, lead, molybdenum, nickel,
silver, vanadium, and zinc (USGS 1994). In addition,
there is the potential for production of synthetic fuels in
the Upper Colorado River and its tributaries by the
extraction and processing of oil shale and/or coal, which
would require significant quantities of water. A synfuels
production level of 3 million barrels per day (oil
equivalent) could consume about 450,000 AF of water
annually (U.S. Water Resources Council 1981 ).

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Xcel Energy owns and operates the Shoshone
hydroelectric power plant in Glenwood Canyon 10 miles
upstream of Glenwood Springs. The power plant has a
1,250 cubic foot per second (cfs) water right that was
adjudicated on December 9, 1907, and an additional
water right of 158 cfs decreed on February 7, 1956
(ENARTECH 1995). The capacity of the power plant is
14,400 kilowatts (KW).

Under present water rights administration, junior upstream
water rights can be placed on call by the Shoshone
Demand whenever the flow of the Colorado River at the
power plant is less than 1 ,408 cfs. During most years, the
Shoshone rights place a call on the river from mid-August
through mid-April of the following year. In dry years, the
call is initiated earlier and may begin in early June. A water
right call originating from the Shoshone Demand can affect
a significant number of water users located upstream of
this demand. Areas subject to a Shoshone call include the
Eagle River Basin and all other areas upstream of Dotsero
(ENARTECH 1995).

In addition to the Shoshone plant, the City of Aspen is
licensed by the Federal Energy Regulatory Commission
(FERC) to operate a hydropower facility at Ruedi Dam
and Reservoir. The FERC license recognizes that
Aspen's hydropower production objectives are
subordinate to other uses but allows Aspen to generate
electricity with any flows resulting from operation of the
reservoir (Finding of No Significant Impact [FONSI] No.
EC-1300-02-03).

Hydropower facilities are also located on Green Mountain
Reservoir and Williams Fork Reservoir. Green Mountain
Reservoir has a capacity of 154,645 AF. There are two
generating units at the Green Mountain Power Plant,
capable of producing 21,600 KW (http://www.ncwcd.org).
The Williams Fork Dam & Power Plant sends water and
electricity to the Western Slope when Denver diverts water
to the city elsewhere. Standing 217 feet above the
Williams Fork River streambed, the dam backs up a
reservoir of nearly 97,000 AF of water, and the power
plant's capacity is 3,158 KW (http://www.denverwater.org).

The Piceance Basin holds vast quantities of natural gas
in the seams of its coal formations, representing one of
the largest natural gas reserves in the United States.
Extraction of coalbed methane (CBM) involves removal
of groundwater to release the gas; this water is typically
either discharged to the surface or reinjected.

CDIVI

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