The Transcontinental Aqueduct. Leg 11: From San Carlos Lake to East Diversion dam, a distance of about 60 miles.

Stage 11 is a true delivery of water on demand aqueduct. The San Carlos lake has a storage capacity of a million acre-ft, the ideal buffer from the peak power demand driven uphill stages to the major delivery stage. San Carlos lake is now mostly empty, but will be normally filled to 85% of capacity, slightly less in advance of the winter snow melt. The Lake would look like this:

San Carlos lake, about half full

The Coolidge dam is now decommissioned, the lake is too often empty and the dam suffered damage in the power plant and it was no longer economical to produce power. The retrofitted dam will have a power generation capacity of up to 17,000 cfs the top of the dam is at 2535 ft, the typical water level is at 2500 ft and the drop is 215 feet, giving a maximum power output of 275 MW. In the first pass, the maximum output is 8,500 cfs , and the maximum power output is 135 MW.

The Coolidge dam before rebuilding.

From there the stream follows the Gila River to the East diversion dam and connects to the Tucson leg of the CAP canal, and delivers 600 cfs of water. It it then disconnected to the bottom of the canal.

The East Diversion dam will be reinforced, and the anal capacity will be increased to 600 cfs.
The free flowing Gila River with reinforcements around Hayden and the copper mine.

Whats in it for Arizona? Besides having a reliable flow, Gila river will again be good for fishing if stocked and it will deliver 600 cfs of reliable sweet Mississippi and Arkansas river water to the Tucson area. When fully built out it will deliver up to 275 MW of power.

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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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