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<br />Juan River, The continued depletion of water from the Dolores River would concentrate salts in
<br />the Dolores/Colorado River system; amounting to approximately an 0,8 milligrams/liter (mg/l)
<br />increase as measured on the Colorado River at Imperial Dam. For comparison purposes,
<br />observed concentration at that point was 669 mg/I in 1999 (the numeric salinity standard at that
<br />point is 879 mg/l), There would be essentially no salt loading to the San Juan River due to the
<br />new irrigation of low-saline lands with efficient irrigation systems. This new irrigation'is
<br />compatible with existing contracts that call for water saved as a result of salinity control efforts
<br />be used only in a manner which will not result in any material increase in salinity inflow.
<br />
<br />Several commentors were concerned that water made available as a result of irrigation
<br />improvements completed under the Colorado River Basin Salinity Control Program, as much of
<br />the 8,000 acre-feet is, should not be used for additional irrigation, The objective of the Salinity
<br />Control Program is maintenance of salinity levels found in the mainstem of the Colorado River
<br />as of 1972, while allowing Colorado and other Upper Basin states to develop full use of their
<br />Colorado River Compact apportioned water. The salinity level in the Colorado River is presently
<br />around 669 mg/I, well below the 1972 levels of 879 mg/1. Therefore, there is no conflict between
<br />the Carriage Contract and the Salinity Control Program,
<br />
<br />Although new soils to be irrigated are low in selenium, selenium loading to the San Juan River
<br />may occur during the initial leaching of soils. Overall, selenium Ioadingfrom newly irrigated
<br />lands is expected to be low because of soil quality, irrigation efficiencies, and the relatively small
<br />acreage of new lands, Selenium loading in return flows from newly irrigated lands will, be
<br />monitored by DWCD in cooperation with the U.s, Fish and Wildlife Service (Service),
<br />
<br />Fish and~ Wildlife Resources-- The proposed. action should have little effect on fish and wildlife
<br />resources, Many commentors on the draft EA were concerned with effects on the Dolores River
<br />fishery downstream from McPhee Reservoir. They believed all or a portion of the 8,000 acre-
<br />feet of water should be made available to the Dolores River.
<br />
<br />The downstream trout fishery is presently managed under a fishery "pool" designated in McJ;>hee
<br />Reservoir to provide downstream releases. The pool consists of29,300 acre-feet of water
<br />supplementedbr up to 3,900 acre-feet of water decreed to.downstream senior water rights, Tbe
<br />senior water right supply is dependent upon Colorado water rights administration system and
<br />may not be a firm supply if those rights are abandoned or otherwise not beneficially used under
<br />Colorado water law. A pool of at least 36,500 acre-feet has been suggested to enhance the
<br />downstream fishery. The 8,000 acre-feet of water involved in the Carriage Contract is private
<br />water, not part of, nor available for, the fishery pool. Thus, the Carriage Contract does not
<br />significantly impact the fishery resource.
<br />
<br />
<br />Because the newly irrigated lands are already being dryland farmed, no significant wildlife
<br />habitat losses are projected and minor gains may occur,
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