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172 Towns and communities in the study area include Farmington at the confluence with the Animas; 173 and Bloomfield, Blanco, and Archuleta upstream and Froitland and Shiprock downstream from 174 Farmington. Energy development, agriculture, and tourism and recreation are important 175 industries in the area. In particular, agriculture and recreation are closely related to Navajo 176 Reservoir and its operation and to flow patterns in the San Juan River. 177 The frontispiece map shows the general project area and the figure in Attaclunent A provides a 178 detailed view of the river corridor; the river is demarcated with river mile designations, starting 179 with River Mile 0 above the high water line of Lake Powell and ending at River Mile 225 at 180 Navajo Dam (these River Mile locations will be referred to throughout the text). 181 PROJECT DESCRIPTION 182 The twofold purpose of the proposed alternative (also referred to as the 250/5000 alternative or 183 the preferred alternative) is to (I) develop operating criteria for Navajo Dam and Reservoir in 184 order to assist in creating and maintaining habitat in the San Juan River to help conserve 185 populations and designated critical habitat of the Colorado pikeminnow and razorback sucker, 186 and (2) maintain the authorized purposes of the Navajo Unit, including enabling future water 187 development. 188 Reclamation will meet the flow recommendations for the San Juan River (Holden. 1999) by 189 modifying the operations decision criteria of Navajo Dam to provide sufficient releases of water 190 at times, quantities and durations necessary to help protect endangered fish and their designated 191 critical habitat while maintaining the authorized purposes of the Navajo Unit. This proposed 192 plan is designed to mimic a natural hydrograph downstream from the confluence of the Animas 193 River. The SJRBRlP uses an adaptive management process that involves annual monitoring and 194 continued research, so the flow recommendations may be refined in response to new information. 195 Reclamation expects the Service will periodically review operations to determine if the flow 196 recommendations are being met. This will be done by reviewing operations in light of forecasted 197 inflow and by reviewing river gage data. 198 The spring peak release will be planned to meet the statistical requirements of the spring flow 199 recommendations and will involve 5,000 cubic feet per second (cfs) releases from Navajo Dam. 200 The decision chart on the following page will be used to determine spring releases. The summer, 201 fall and winter base releases are also intended to meet the flow recommendation targets in the 202 river downstream of Farmington of 500 to 1,000 cfs for habitat protection and water storage. 203 204 The proposed operation would meet existing water development commitments as well as meet or 205 exceed endangered fish spring peak recommendations. The endangered fi.sh minimum base 206 flows downstream from Farmington (500 cfs) would be met consistently under this operation. 207 Maximum recommended base flows (1,000 cfs) downstream from Farmington would 208 occasionally be exceeded because of high inflows from the Animas River--this could occur even 209 with 250 cfs releases from Navajo Dam. The average flow at two of the four gages downstream 7 . .