WSP08927

• File Number: 8141.600.20
• Description: Fryingpan-Arkansas Project - Studies - Environmental Studies
• State: CO
• Basin: Arkansas
• Water Division: 5
• Date: 10/12/1983
• Author: US DoI BoR
• Title: Draft Supplement to the Final Environmental Statement Fryingpan-Arkansas Project Colorado
• Water Supply Pro - Doc Type: EIS

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2.2

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The minimum reservoir content in an average year, such as 1974, during

the summer recreation period (June-August) would be about 94,100 acre-feet and

would be about 48,600 acre-feet in the dry year of record, 1977. The reser-

voir con'tent exceeds the content of 52,000 acre-feet necessary for use of the

Forest Service boat ramp in all but the driest years. Releases to the
Fryingpan River in ~e winter months would range from 104 ft3/s 124 3
to ft /s
in an from 27 ft3/s 3
average year and to 100 ft /s in a typical dry year.

These flows meet or exceed the minimum release requirements of the operating

principles for the protection of recreational values, including fishing on the

Fryingpan River below Ruedi Reservoir.

The water demand pattern for this alternative and the actual demand fre-

quency are shown in Table 2.1, The actual demand for water from Ruedi

Reservoir is stimulated by shortages on the Colorado River. As can be seen

from Table 2.1, the frequency of water demand from Ruedi increases in the

months when the Colorado River is at its lowest, and overall demand for water

from the Colorado River is high (April through October) by agriculture, muni-

cipalities and industry. Water not supplied by Ruedi Reservoir to meet the

base water demand is assumed to be met using water rights for direct flow from

the Colorado River or a tributary.

The pattern of reservoir levels and Fryingpan River instream flows below

Rocky Fork Creek are illustrated in Figure 2.1 for the dry and wet years of

record (1977 and 1957, respectively, for the period 1948 to 1980) and for an

average year inflow to the reservoir, 1974. These graphs serve to illustrate

the effects of the preferred alternatives operation on the reservoir and

affected downstream river reach.

No Action. Alternative Describes the Present Operating
Conditions

This alternative reflects the present level of water sales from the

reservoir and the present reservoir operational practices. The present reser-

voir operation allows for filling of the reservoir during the late spring and

early summer. Reservoir releases are made to meet senior water rights demands

downstream of Ruedi Reservoir or to compensate downstream water users for out-

of-priority diversion by the collection system of the Fryingpan-Arkansas

Project. Fall, winter and early spring releases are made from the reservoir

to provide adequate storage for spring runoff.