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I 'J '.' ~ ~ .. '" ~ 002215 e e in the Colorado River associated with any of the alternatives would not adversely impact this species. The proposed action would be beneficial compared to the no action alternative since the chronic 20 cfs flow during dry years would be avoided. Lower flows associated with the proposed action would occur during the winter, but based on studies conducted over the last three years, flow is not expected to be dropped below 30 cfs during this period. The highest flow would be provided downstream of the dam duri~g summer months. If a sufficient volume of w~ter was available, flow no less than 70 c=s would be provided during the hottest summer periods.. A 20 cfs flow was considered by Valdez, et al., (1992) as being extremely detrimental to aquatic life. They concluded, however, if sufficient flows were present, the Dolores River would have suitable habitat for reintroduction of experimental populations of Colorado squawfish. It is not known what magnitude of flow would be needed at this time. The Service has no immediate plans for relntroducin~ an experimental population of Colorado sguawfish in to the Dolores River in the near future (pers. corom. John Hamil, USFWS, 1994). Recl~~ation does not believe that implementation of the proposed action would affect either the Colorado squawfish or its' critical habitat in the Coloraco River. RAZO~CK SUCKER, BONYTAIL CHUB, HUMPBACK CHUB 7he razorback sc:ke=, bony~a~l chub and ~he humpback ch~b have all bee~ ~e?cr~ec from ~he Colorado River cown5~re~~ 0: i~sr co~fluence ~~~~ the Dolc=es R~ve=. None c= ~hese species have eve~ been =epo~~ec ==c~ ~he Dolores Rive~. As concluded above for the Colorado squawfish, Rec:amatic~ does ~ot believe implementation of the proposed action would directly affect either the s?ecies or ~ne~= ?roposec c=~~ical habi~a~ in the Colc~ado River. SAN JUAN RIVER BASIN DOLORES PROJECT R-~ FLOWS The Dolores Projec~ diverts wa~er from the Dolores River basin for ~rrigation, municipal and industrial (M&!) use in ~he San Juan River basin. Projec~ water return flows enter the Sa~ Juan River via the Mancos River, Cowboy Wash, Marble Wash, McElmo Creek, and Montezuma Creek. Average annual Project return :lowswere estima~ed as 50% re~urn from ~he municipal and industrial. wa~er diverted, 18% of the full service irrigation water delivered on farm, and 35~ of the supplemen~al irriga~ion wa~er delivered on farm. Following is the estima~ed average annual return flows associated with each use under full Project development. ~ Municipal & Industrial. ;'.~~e-Feet 4,350 Irrigation Full Service Supple~en~al Se~vice :S,ESC ~ Pf"'If"\ .....~.... -:::J~c.2. =~!coc