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Table 6, Representative Monthly Flows With and Without the Project-Dolores River at McPhee Wet Year Normal Year Dry Year (second-feet) (second-feet) (second-feet) Pre- Post- Pre- Post- Pre- Post- Project Project Project Project Project Project March 140 90 100 60 70 20 April 2,190 920 980 60 170 20 May 1,280 1,940 1 ,420 240 470 20 June 1,150 460 1,030 290 130 20 July 60 78 70 50 0 20 August 30 78 70 50 20 20 September 20 78 100 50 10 20 October 20 78 90 50 20 20 November 30 78 50 50 40 20 December 40 78 60 50 40 20 January 40 78 50 50 50 20 February 50 78 60 50 50 20 Source: USBR, 1977 3. The maximum allowable diversions, based upon the total capacity of the Dolores Tunnel and the Great Cut Dike (1,340 ft3/s), were subtracted from the computed spills. 4. The resulting outflows are only to be used as an indication of potential 7-day outflows to the Dolores River after total completion of the Dolores Project. Of the 14 years of record modeled, the following 7 -day high flows were determined for the upper river: 8 years or 57 percent had flows greater then 700 ft3 Is 7 years or 50 percent had flows . greater than 900 ft3 Is 6 years or 42 percent had flows greater than 1100 ft3/s 20 5 years or 36 percent had flows greater than 1300 ft3 Is 4 years or 28 percent had flows greater than 2500 ft3 Is 1 year or 7 percent had a flow greater than 3700 ft3/s From this analysis it was assumed that the 1.5- year recurrence interval 7 -day high flow will be approximately 1,000 ft3/s for the upper river. Thus the channel forming flows expected to be released after full development of the Dolores Project are approximately 1000 ft3/s. The outlet works at McPhee Dam, as stated in the DPR and verified in conversations with the Cortez Project Office (personal communication, Mr. Mutz, Oct. 1989), will be operated to allow for release through the outlet works of inflow design floods between 1,000 and 2,500 ft3 Is. Releases of