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I I I I I I I I I I I I I I I I I I I 3.3 Outlet Works Foll owi ng a revi ew of the hydraul i cs of the exi sti ng outl et works, three criteria were evaluated. These included: 1) The capacity of the outlet works to release the maximum five feet of reservoir storage at a rate of one foot per day, 2) The out1 et capacity requi red to insure the current reservoi r operating restriction will be maintained, and 3) The outlet capacity with regard to the normal flow. The mai n outl et works di scharge rati ng curve, as developed by Nel son, Haley, Patterson and Quirk for the 1973 dam modifications, was reviewed and found to be acceptable. The SEO requires that the outlet works have the emergency capacity to release the maximum five feet of reservoir storage at a rate of one foot per day. The net storage in the five feet below the normal water surface elevation of 9087 (G.H. 40.0) is approximately 523 acre-feet. From the revised outlet stage-discharge curve, at an average elevation of 9084.5 (G.H. 37.5), the computed discharge is 155 cfs. This is equivalent to a volume of 1,537 acre-feet for a five-day peri od. Therefore, the out1 et works is capab1 e of discharging the maximum five feet of storage in less than five days, assuming there is no additional inflow into the l'eservoir. Barnes Meadow Reservoi r is currently restri cted to a maximum water surface elevation of 9083 (G.H. 36). This elevation corresponds to an outlet works di scharge capaci ty of 152 cfs. Although no di scharge measurements have been made at Barnes Meadow Reservoi r, measurements are avail abl e at a gaged si te representing a similar basin. USGS discharge measurements at Fall Creek, near Rustic, are available for the period 1961-1973. The measurements were adjusted to reflect the slightly different drainage areas. Review of these 1231 H -64-