The Theodore Roosevelt Dam is located about 76 miles northeast of Phoenix and 30 miles northwest of Globe, Arizona. The project was so important to local agriculture that the Salt River Valley Water Users' Association (created by Phoenix area farmers) offered their land as collateral to finance the $10 million project. The project started in 1905 and was suppose to be completed in two years. It took three times that due to flooding and washouts. I can only imagine how frustrating this project would have been to all the people involved in the process.
A challenging aspect of the Theodore Roosevelt Dam modification project was designing a concrete overlay for the dam that would be compatible with the underlying masonry structure. The Bureau of Reclamation chose a single-curvature approach using conventional mass concrete placed in 10-feet high, 70-feet wide blocks, ranging in thickness from 10 to 50 feet. The first concrete block was placed in September 1992 and the final block was placed June 28, 1995 raising the dam to 357 feet tall. The additional 77 feet of dam height increased the water conservation storage capacity by 20 percent and provides for more than 1.8 million acre-feet of flood storage. The new mass concrete blocks with vertical joints were placed as alternating odd-even cantilevers. Reclamation's quality control testing program requires close inspection of the concrete batching and placing operations, and regular testing of cast concrete and concrete components. Mass concrete compressive strengths average 800 pounds per square inch in seven days based on 12 by 24 inch cylinders, and 4,500 pounds per square inch in one year based on 12 inch cores. (source)
Wikipedia: Theodore Roosevelt Dam
Bureau of Reclamation: A Brief History of the Roosevelt Dam
Bureau of Reclamation: Theodore Roosevelt DamThe Arizona Experience: Theodore Roosevelt Dam: A Century of Power
Arizona Daily Star: Photo Gallery: Theodore Roosevelt Dam Today
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