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Projected Plan of Operation - Water Year 1985 Porker Dam. Regulatory Wastes Deliveries to Mexico consist of river water delivered to Imperial Dam and waste and drainage return flows from water users I' below Imperial Dam. In addition to . assuring normal water deliveries, the small amount of regulatory storage space in Imperial, Laguna, and Senator Wash Reservoirs was used at times to limit potential downstream flood damages during water year 1984. Regulatory waste for water year 1985 will depend on the actual hydrologic conditions occurring during that time. A proposed operation plan for water year 1985 for major reservoirs of the Colorado River system WQS formulated and distributed to representatives of the Colorado River Basi" States in November 1984. This plan was prepared in accordance with the Operating Criteria published June 4, 1970, in compliance with Section 602, Public law 90.537. The plan reflects operation for flood control, irrigation and other domestic use of water, hydroelectric power generation, water quality control, fish and wildlife propagation, recreation, and Colorado River Compoct requirements, The -plan .was very "similar to" the-plan" -- developed for water year 1983 which was based on the need to develop sufficient reservoir space by January 1, 1985, to reduce the risk of reservoir spills. The record high runoff of water year 1984 had again left all of the system reservoirs essentially full, requiring large releases to draw the reservoir system dawn. Releases at maximum powerplant capacity will most probably continue at Glen Canyon until at least January 1985 in order to develop sufficient vacant reservoir space to reduce the risk of spilling. This also reduces the risk of damaging flood control releases from Hoover, Davis, and Parker Dams, should large runoff forecasts occur during the 1985 runoff period. Releases from January through July will be based upon the runoff forecasts received during that time but will result in greater available space on August 1, 1985, than the minimum flood control requirement of 1.5 mof. The plan calls for 0 total Glen Canyon release in water year 1985 of 10.7 maf under reasonable minimum inflow conditions. This would essentially equalize the active contents of Lake Powell and lake Mead by the end of the water year. An annual release of 13.8 mof would be required under most probable inflow conditions, which would fill lake Powell and also equalize the active contents of lake Powell and lake Mead by September " 30, 1985. With a reasonable maximum inflow during water year 1985, the projected Glen Canyon release would be 18.1 mat. This volume of inflow would require maximum powerplant releases for all of water year 1985 to ovoid the use of Glen Canyon's river outlet works or spillways. The projected operation for most probable runoff conditions for each reservoir in the Colorado River Basin for water year 1985 is described in the following pages. Charts 1 through 8 show the projected monthly outflows from each reservoir for three assumed hydrologic conditions. Each of t!1e_se_ a_s~u_rT'!p}ig':l.! ~s~s_ !h,!t !'lost current hydrologic information available by including actual forecasted October through December 1984 inflows. The monthly inflows for the remainder ot the year were based upon the following assumptions: (1) most probable based upon the 1906 through 1983 natural flows developed for the Colorado River Simulation System (CRSS) depleted up to the 1985 level; (2) reasonable minimum based upon the annual volume of inflow which would be exceeded about 90 percent of the time; and (3) reasonable maximum based upon the annual volume of inflow which would be exceeded about 10 percent of the time. 5