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The Mokelumne Aqueduct is a water conveyance system in central California, United States. The aqueduct is supplied by the Mokelumne River and provides water to 35 municipalities in the East Bay in the San Francisco Bay Area. The aqueduct and the associated dams, pipelines, treatment plants and hydroelectric system are owned and operated by the East Bay Municipal Utility District (EBMUD) and provide over 90 percent of the water used by the agency. The aqueduct is the sole water supply for about 1.4 million people in the East Bay.〔 Under present water rights agreements, EBMUD can withdraw up to 325 million gallons (1,230,000 m3) per day, or per year, from the Mokelumne River. In addition, up to 98 million gallons (371,000 m3) per day or per year can be supplied via a branch from the American River. However, this supply is expected only to be used in the driest 35% of years. ==History== In the early 20th century, due to a lack of reliable local water, Bay Area cities began to look to rivers in the Sierra Nevada, about east, as a potential new source. Although the city of San Francisco was already extending an aqueduct to the Tuolumne River, East Bay communities wanted to build an independent water system, fearing future "hegemony" of the water system by San Francisco. In 1923, the EBMUD was organized and in 1924 acquired water rights to the Mokelumne River, a major tributary in the San Joaquin River system.〔(【引用サイトリンク】title=History )〕 On November 4, 1924 residents approved $39 million in bonds to finance the project. Construction began in 1926 and by 1929, the high, concrete arch Pardee Dam and the First Mokelumne Aqueduct, consisting of a single pipeline, were completed. The first deliveries to the Bay Area were made on June 23, 1929. At the time of completion, Pardee Dam was the tallest in the world (this record was surpassed one year later by Diablo Dam in Washington State). In 1949, a second pipeline was built and in 1963 the third pipeline was constructed, bringing the aqueduct to its present capacity.〔 In 1964, the second major dam of the project, Camanche Dam, was completed below Pardee. In 1970, EBMUD signed a contract with the U.S. Bureau of Reclamation (USBR) for supplemental water from the Folsom South Canal, which draws water from the American River near Sacramento. The USBR supply was delayed for nearly 40 years in part due to minimum flow requirements in the American River to protect salmon and steelhead populations. The Folsom South Canal Connection (FSCC), which links the two waterways, was finally completed in 2009. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mokelumne Aqueduct」の詳細全文を読む スポンサード リンク
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