which dam is built over it?
Coolidge Dam
Gila River
The only major dam on the Gila River is Coolidge Dam, southeast of Globe, Arizona, 
who negotiated the purchase of the area south of gila river UNANSWERABLE what do you mean by this purchase? It is a region of present-day southern Arizona and southwestern New Mexico. is there any person after whom this area is named? James Gadsden who was this person? An American diplomat, soldier and businessman. why is the above place related to him? The first draft was signed on December 30, 1853, by him. for what was this draft signed? For the purchase included lands south of the Gila River and west of the Rio Grande. where is this mentioned river located? United States
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Gila River [SEP] Dams and diversions
The only major dam on the Gila River is Coolidge Dam, southeast of Globe, Arizona, which forms San Carlos Lake. The Painted Rock Dam crosses the Gila near Gila Bend, although the river is a transient one at that point. A number of minor diversion dams have been built on the river between the Painted Rock Dam and the Coolidge Dam, including the Gillespie Dam, which was breached during a flood in 1993. Many dams have also been built on tributaries, including Theodore Roosevelt Dam on the Salt River, New Waddell Dam on the Agua Fria River, and Bartlett Dam on the Verde River.