The Transcontinental Aqueduct. Leg 11: The highest pumping station in Arizona to San Carlos Lake, a distance of 93 miles.

The aqueduct stage of this leg is 32 miles and is generating power.The drop is average (4,200 – 3,000 – 32×2.2) = 1,130 feet. The maximum flow is 16,800 cfs. This stage is capable of generating maximum 1.4 GW of power 24 hours a day. Then it drains into Gila River for 47 miles, following 14 miles of San Carlos lake, for a total of 93 miles.

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 contained (April 6,2021) less than 100 acre-ft of water. All fish was dead.

When former President Coolidge dedicated the dam in 1930, the dam had not begun to fill. Humorist Will Rogers looked at the grass in the lake bed, and said, “If this were my dam, I’d mow it.”[

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, or better:

The San Carlos lake, when filled will hold 1,000,000 acre-ft of water.

The Coolidge dam will have to be retrofitted for a 25,000 cfs water flow

The Coolidge dam will have to be retrofitted for a 17,000 cfs water flow. When water starts flowing at half capacity, 8,400 cfs in phase 1 of the building project it will take 2 months to fill the lake.

What’s in it for Arizona? The San Carlos Lake has been a great disappointment. It is more often empty than even half full, and when it is empty, all fish die. With The Gila river will be rejuvenated and will be able to carry fish again, making it the great recreation spot it was meant to be. In addition it will generate up to 1,4 GW of Power and carry up to 12 Million Acre-ft per year of water to the thirsty American South-west. In the first phase, while the aqueduct is built to full capacity, the flow will be 6 MAf per year.

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Retired engineer, graduated from Chalmers Technical University a long time ago with a degree in Technical Physics. Career in Aerospace, Analytical Chemistry, computer chip manufacturing and finally adjunct faculty at Pennsylvania State University, taught just one course in Computer Engineering, the Capstone Course.

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