Stage 10 was a true pumped hydro-storage peak power stage, producing up to 11.0 GW electric power for up to 5 hours a day. In stage 11 the flow will be a maximum flow of up to 25,000 cfs, but with periods of less flow during low electricity demand, all to accommodate both water needs and power demands.
The power generating drop is on average (4320 – 2510 – 80×2.2) = 1,634 feet. This stage is capable of generating maximum 2.4 GW of power during all times.
San_Carlos_Lake is located within the 3,000-square-mile (7,800 km2) San Carlos Apache Indian Reservation, and is thus subject to tribal regulations. It has been full only three times, in 1993 it overflowed the spillway and about 35,000 cfs of water caused erosion damage to natural gas pipelines. The lake contains now (April 6,2021) less than 100 acre-ft of water. All fish is dead.
When the Transcontinental aqueduct is built the lake will always be nearly filled, level will be at 2510 feet with flood control nearly automatic, it will never overflow, and it will look like this:
The Coolidge dam will have to be retrofitted for a 25,000 cfs water flow