WSP09722

• File Number: 8220.106
• Description: Animas-La Plata
• State: CO
• Basin: San Juan/Dolores
• Water Division: 7
• Date: 2/26/1996
• Title: Final Biological Opinion - 1996
• Water Supply Pro - Doc Type: Biological Opinion

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Phase I, Stage B would involve the development of a total project water supply
of up to 169,710 acre-feet. Additional project facilities associated with
Stage B would be: a full sized Ridges Basin Pumping Plant, Long Hollow
Tunnel, and the Dryside Canal to the Dryside Lateral Turnout. Completion of
Phase I would provide project water at Ridges Basin Reservoir for the Southern
Ute Indian and Ute Mountain Ute Tribes, irrigation facilities and water to
serve most of the non-Indian and Southern Ute Tribal Project lands, in
additional to the entire M&I water supply provided under Phase I, Stage A.
Additional pumps needed for the completion of Phase I would be added to
Durango and Ridges Basin Pumping Plants, which would satisfy the requirements
for Phase I and II. The Southern Ute Diversion Dam and an interim extension
of the Southern Ute Inlet canal would be constructed to service irrigated land
in New Mexico. If Stage B were constructed, water supply for the La Plata
rural water users would be delivered via the Dry Side Canal to a point along
the canal near the Red Mesa Pumping Plant, and the La Plata Rural Pipeline
would not be constructed.

Phase II would develop a total water supply of up to 191,230 acre-feet
(average annual depletion of 149,220 acre-feet). Additional facilities would
include: Southern Ute Dam and Reservoir; La Plata Diversion Dam; the
remaining portion of the Southern Ute Inlet Canal; the Dry Side Canal would be
extended to near the Ute Mountain Ute Reservation boundary; New Mexico
Irrigation canal; Alkali Gulch, Ute Mountain, Southern Ute, and the Third
Terrace Pumping Plants; and the laterals to serve Phase II lands. With the
completion of Phase II, all Project lands, with the exception of those above
the Dry Side Canal, would be served by sprinkler irrigation.

Ridges Basin Reservoir, the primary storage facility, would be located on
Basin Creek, an intermittent tributary to the Animas River, southwest of
Durango, Colorado. The reservoir would have a maximum capacity of 273,100
acre-feet--127,900 acre-feet of active, usable capacity and 145,200 acre-feet
of inactive and dead storage. Average evaporation from Ridges Basin Reservoir
is estimated at 3,300 acre-feet annually. Secondary storage would be provided
at Southern Ute Reservoir, an offstream facility located about 2 miles east of
the La Plata River on the Colorado-New Mexico State line. Southern Ute
Reservoir would have a maximum capacity of 70,000--40,000 acre-feet of active,
usable capacity and 30,000 acre-feet of inactive and dead storage. Average
evaporation from Southern Ute Reservoir is estimated at 3,300 acre-feet
annually. None of the above depletions will occur until completion of the
Ridges Basin Dam and Durango Pumping Plant. Upon completion of the Project,
full development and operations would result in a average annual depletion of
149,220 acre-feet of water.

The Project would pump water from the Animas River via the Durango Pumping
Plant, through Ridges Basin inlet conduit to Ridges Basin Reservoir for
storage. Stored water would be used for irrigation and industrial needs of
the Southern Ute Indian and Ute Mountain Ute Tribes and the Navajo Nation;
other Colorado and New Mexico irrigators; and municipal and industrial uses
for Durango, surrounding communities, and northwestern New Mexico. During
low-flow periods, stored water would be released down Basin Creek, back to the
Animas River to meet Aztec, Farmington, and other municipal and industrial
needs in New Mexico. Additionally, stored water would be pumped through