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SUMMARY (Continued) • Drains and Washes Under the no-action alternative, the aquatic resources of the drains and washes would remain in their present poor quality condition, with little or no recreational use. The discharge and water quality in the drains and washes of the Grand Valley would be altered by developing either alternative A or B. In general, major drains and washes with year-round flow would have in- creased flow and decreased salinity during the irrigation season and decreased flows during the nonirrigation season. Some of the smaller intermittent drains, dependent entirely on seepage, would be dried up. Vegetation Under the no-action alternative, a gradual but continuous loss of native vegetation in the valley would likely occur as a result of urban expansion, farm improvements, sand and gravel production, and other fac- tors. Marsh and cottonwood vegetation types would be particularly af- fected because of their scarcity. Stage One wildlife measures would be implemented to offset wildlife losses associated with Stage One improve- ments. • Alternatives A and B would have similar impacts on the vegetation of the valley. Short-term effects for both alternatives include clearing vegetation (about 3,300 acres or an average of 165 acres each construc- tion year) within construction rights-of-way, while long-term effects would be related to reduced ground water which supports wetland vegeta- tion. A net acreage loss of 200 to 300 acres of wetland vegetation types would occur with either alternative. Wildlife The Fish and Wildlife Service prepared a Coordination Act Report (1984) assessing unit impacts and recommending measures to offset losses. Under the no-action alternative, the wildlife in the valley would gradu- ally be reduced with conversion of habitat to urban, industrial, and agricultural uses. Riparian habitat losses along the Colorado River would be especially significant because of the present scarcity of this type of habitat and because of its importance to wildlife. Wildlife measures for Stage One would be implemented to offset habitat losses now occurring due to Stage One construction. Under alternatives A and B, additional wildlife losses would occur primarily as a result of clearing habitat during construction and long- term losses of habitat caused by seepage reduction from canals and lat- erals. The detention dike and ditch system would increase moisture available for plant growth north of the Government Highline Canal which, in turn, would benefit local wildlife populations. Observations in Stage One have indicated that habitat losses have occurred in zones along canals and laterals, while changes are not readily apparent outside of S-7