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It is along the Colorado River that “the most celebrated showpieces of American water engineering have appeared.”1 In the process of furnishing water to nearly 30 million people and 3.7 million acres of farmland in seven western states and northern Mexico, the Colorado has become one of the most dammed, diverted, and (over)regulated rivers in the land; in fact, it is “a river no more,” according to Philip Fradkin, who documented the Colorado’s decline from its headwaters to the Gulf of California.2 We have seen that the river’s transformation began more than a century ago near Yuma with the construction of Laguna Dam. This early irrigation project would lead to subsequent developments on the Colorado that would result in unforeseen troubles decades later. Excluding Laguna, eight dams now straddle the Colorado; some serve to regulate the river’s flow, while others function to divert its flow. Today, Laguna Dam has been reduced to a regulating structure for the small reservoir found behind it, which is now used for recreation. Laguna’s utility as a diversion structure for the Yuma Project has been supplanted by Imperial Dam, completed in 1939 a few miles upriver, which diverts Colorado River water into the All-American Canal , serving the Imperial and Coachella valleys, as well as the Yuma Project. The more noteworthy issues and concerns involving the subsequent storage and diversion projects on the Colorado are the subject of this final chapter. The All-American Canal The great dam-building era and ensuing activities associated with industrial irrigation on the Colorado grew out of the need to regulate the cycles of flood and drought that characterized the annual flows of the river. Uncontrolled , the Colorado was of limited value, particularly in the rapidly growing Imperial Valley, where sediment deposits and irregular flows compromised water deliveries.3 Laguna Dam, then serving as a diversion structure for the i฀10 j Epilogue 206 t h e y u m a r e c l a m at i o n p r o j e c t Yuma Project, was not designed to regulate the lower Colorado River’s flow. Imperial Valley interests, who were not anxious to experience another disaster similar to the one they had endured from 1905 to 1907 during the Colorado River breach, began to campaign for the construction of a storage dam to control the river, and a canal that would carry water from the Colorado River to the valley without crossing the border into Mexico. In 1919, the Imperial Irrigation District (successor to the California Development Company that purchased the defunct corporation’s irrigation works) forged a partnership with the long-resisted Reclamation Service to determine the feasibility of constructing an “All-American Canal” to carry water from the Colorado River to the Imperial Valley. Consequently, a comprehensive survey of the lower Colorado River basin was undertaken, which culminated in the so-called Fall-Davis Report, submitted to Congress in 1922. Arthur P. Davis, who, as noted earlier, was fixated on the conquest of the Colorado River, now served as director of the Reclamation Service. His agency was responsible for conducting the survey of the lower Colorado River , the findings of which were turned over to Interior Secretary Albert Fall. The resulting “Fall-Davis Report” recommended a comprehensive development scheme to regulate the river, generate power, and irrigate the lower Colorado Valley.4 In order to accomplish this, Davis advocated approval of the Boulder Canyon Project involving the construction of a large storage dam, later to become known as Hoover Dam, in the vicinity of Boulder Canyon , and the completion of an “All-American Canal” leading from the Colorado River to the Imperial Valley, bypassing Mexican territory. Twenty years earlier, Davis had recognized the need for such a dam as part of a comprehensive plan to develop the river. The dam would be paid for by leasing the right to generate power, while the reservoir behind it would lessen siltation and prevent major flooding downstream, and ensure the availability of water to growers. The All-American Canal was estimated to cost thirty million dollars, but its repayment by Imperial Valley irrigators would be spread over many years interest free, in accordance with the 1902 Reclamation Act and its subsequent amendments.5 And most of the money would come from power revenues collected by the Imperial Irrigation District from generating facilities located along drops in the canal. Consideration was given to using the existing Laguna...

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