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0017.J8 could involve dam releases of 5000 cfs for peak spring flows followed by lower releases ranging from 250 to 500+ cfs during the remainder of the year. Purpose The Test provides data needed for the preparation of the EIS and for comparison with results of a 1996-97 winter low flow test (Reclamation 1998). Public and agency concerns arose when it became widely known that low flows of 250 cfs could occur in the summer as well as during the winter-in fact, at any time other than the spring peak flow period (usually 2 to 3 weeks in May and early June). Generally, as outlined in the Flow Recommendations, releases from Navajo Dam to the San Juan River can be broken into a spring peak release of 5000 cfs and lower releases required to maintain year-round flows of 500- 1,000 cfs in the endangered fish critical habitat (downstream of Farmington, New Mexico, to lake Powell). Releases from the dam could be decreased to as low as 250 cfs under the following scenarios: (1) Tributary inflows cause the critical habitat reach of the river to approach the upper end of the 500 to 1000 cfs flow; and (2) reduced releases are necessary to store water in Navajo Reservoir to enable spring peak releases to be made the following year and to store water for development. Public concerns with a 250 cfs release included water quality issues, possible trout stranding, loss of trout habitat, curtailed rafting, flows too low to permit agricultural, municipal and industrial water diversions, loss of revenue by area businesses, and power generation problems. The Test, held to evaluate these concerns, was preceded by public meetings and the preparation of an Environmental Assessment! Finding of No Significant Impact to analyze impacts of the Test itself. -2- Summer Low Flow Report - November 2001