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History of The Roosevelt Dam

First electricity delivered to Valley on permanent basis started Oct. 1, 1909

What started 100 years ago as a simple way to furnish electricity for use during construction of Theodore Roosevelt Dam has helped transform the once sleepy Salt River Valley into the nation's fifth-largest metropolitan area.

That kind of growth would have been hard to imagine on Oct. 1, 1909, the day power was delivered for the first time on a permanent basis from the hydroelectric facility at Roosevelt Dam to the Pacific Gas & Electric Co. of Phoenix's brand new substation in Phoenix. So too would the fact that a century later the greater Phoenix metropolitan area uses more electricity on a typical summer day than New York City.

It wasn't as simple as it seems today, however. Early on, the landowners who founded what now is SRP saw the power business as a way to match need with opportunity. While Roosevelt Dam -- the cornerstone of the new SRP water-delivery system -- wasn't dedicated until 1911, several years after construction began, it didn't take long to realize that a byproduct of the dam and the Valley's canal systems was hydroelectric power.

The National Reclamation Act, signed by President Theodore Roosevelt in 1902, provided federal loans for construction of reclamation projects in the West. Salt River Valley settlers formed the Salt River Valley Water Users' Association in 1903 and pledged their land as collateral for a federal government loan to build a massive water storage and delivery system.

"That first power delivery, three years before Arizona would achieve statehood, helped set up power as the 'paying partner' for the water reclamation project and establish Salt River Project as the first multipurpose reclamation project," said Shelly Dudley, a senior historical analyst at SRP.

Today, as SRP's electric customer base has grown to about 930,000, hydropower from Roosevelt Dam and the three other hydro facilities on the Salt River is one part of a resource portfolio of clean renewables -- including solar, wind, geothermal and biomass -- that makes up about 6 percent of SRP's annual generation mix.

While Oct. 1, 1909, was when power was delivered for the first time on a permanent basis to Phoenix, there were hurdles that had to be overcome to get there, Dudley said. Power production actually began at Roosevelt Dam in March 1906, if only on a trial basis. Three months later, Roosevelt Dam's power plant began operating 24 hours a day.

The transmission line between Roosevelt Dam and the Valley was completed in July 1909. And, on Aug. 1, 1909, power generated at the dam was first delivered -- by way of Mesa -- to Phoenix. The current that day only flowed for a few minutes, Dudley said, before the U.S. Reclamation Service inspected the transmission lines and generation equipment for abnormalities, and nothing out of the ordinary was reported.

Electric power lines were such a novelty then that when the line was about to be energized, Reclamation issued a public warning to parents that children should be kept away from the poles because some children were making a habit of climbing the poles and grabbing the wires. The warning stated, "The Reclamation Service gives warning to everybody between here and Roosevelt, that the power is likely to be turned on. … The warning is now given that there is danger and plenty of it, and if the warning is not heeded somebody may be killed. Parents will do well to impress these facts on their children."

Once the hydroelectric generator at the Roosevelt Dam site -- located 76 miles east of Phoenix -- began producing on a regular basis, excess electricity was delivered to wells and industrial customers in the Valley. An Arizona Republican editorial entitled, "A New Era for the Valley," proclaimed, "… the installation of this electric service is an epoch marking event. Over sixty miles in length, a line having no superior in the world, electric power is conveyed from the great Roosevelt Dam to the Salt River Valley." Initially, only half-a-dozen customers were served by the Roosevelt hydroelectric plant.

By 1912, the year Arizona became the 48th state, SRP had entered into a contract with Inspiration Consolidated Copper Co. of Miami to supply hydroelectric power to its nearby mines. That contract essentially assured the viability of SRP's electric system, Dudley said. Soon the copper industry expanded, the Valley grew and SRP extended its power service. In the 1920s, three more hydroelectric dams were built below Roosevelt at Horse Mesa, Mormon Flat and Stewart Mountain. By 1928, SRP was stringing a local electric delivery system that resulted in the electrification of the Valley's rural areas nearly 10 years before the National Rural Electrification Act brought power to the rest of rural America.

The investment made by SRP shareholders in the early 1900s was rewarded in October 1955, when the final payment of construction costs for Roosevelt Dam, Granite Reef Diversion Dam and other appurtenant works was made to the United States Treasury. That investment continues today, with SRP now the largest provider of water and power to the greater Phoenix metropolitan area.

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