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<br />001585 <br /> <br />Reach 2: La Plata River from Long Hollow confluence to Cherry Creek confluence (-6 <br />river miles): speckled dace, flannelmouth sucker, bluehead sucker, mottled sculpin, and <br />occasional roundtail chub (Miller, 1995). Flows in this reach periodically dry up, but <br />native fish are able to re-colonize by moving upstream from below Long Hollow Creek, <br />which presently flows year-round due to irrigation return flows. <br />Reach 3: Long Hollow Creek and its tributaries: speckled dace, bluehead sucker, <br />flannelmouth sucker. A CDOW stream survey in 1975 showed speckled dace and <br />bluehead sucker were present in Long Hollow Creek. A CDOW stream survey in 2002 <br />showed flannelmouth sucker were present in Government Draw. Recent fish survey <br />information is lacking for Long Hollow Creek at the proposed reservoir site. During the <br />recent drought, flows in Long Hollow Creek have been the only perennial source of water <br />for the lower La Plata River. Long Hollow Creek could be a refugium for native fishes. <br />Additional fish surveys are needed for Long Hollow Creek and Government Draw at the <br />site ofthe proposed reservoir. <br /> <br />It is assumed the native fishes inhabiting the -1/2 mile reach from Long Hollow Dam <br />site to the confluence with the La Plata River would be permanently lost. Further, it is <br />assumed that all native fishes currently inhabiting the proposed reservoir basin (lower <br />Long Hollow Creek and Government Draw) would be permanently lost when stream <br />habitat is inundated. <br /> <br />II. La Plata River flow recommendations. <br /> <br />Lack of long term hydrological data for Long Hollow Creek rnakes it difficult to assess the total <br />impact ofthis project. In the BA, major assumptions for modeling the impacts of Long Hollow <br />Reservoir are based on only ten years of stream gage data (1988 to 1998). It is generally <br />recognized that irrigation return flows contribute significantly to base flows in the La Plata River <br />below the Cherry Creek and Long Hollow confluences. For example, in January, 2004, Long <br />Hollow Creek contributed about 50% of the base flow in the La Plata River from Long Hollow <br />to the state line. <br /> <br />A description ofthe anticipated impacts of the proposed reservoir to native fishes is found in the <br />BA: "Typically, stream flow will decrease during the non-Compact period from December 1 st <br />through February 15th and will be equal to or greater than the pre-reservoir stream flow during <br />the remainder ofthe year.. ..Potentially significant adverse impacts may result to the state <br />sensitive roundtail chub and flannelmouth sucker.... Reduced base flows during the winter <br />months (the non-compact period from December I-February 15) may result in habitat loss for <br />roundtail chub and increased vulnerability of fish to freezing temperatures and predation from <br />birds.. ..Native fish may not withstand... the spiking flows to the La Plata River from the <br />reservoir to meet compact demands...." <br /> <br />Flows to protect native fishes in the lower La Plata River have been recommended by various <br />resource agencIes. <br /> <br />· Appendix I of the Final Supplement to the Final Environmental Statement for the <br />Animas-La Plata Project (March, 1996) identified the need for an 8 cfs fish maintenance <br /> <br />2 <br />