San Joaquin River
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The San Joaquin River, 330 miles (530 km) long, is the second-longest river in California, United States.
It originates high on the western slopes of the Sierra Nevada and drains most of the area from the southern border of Yosemite, south to Kings Canyon National Park, making it the second largest river drainage in the state. The San Joaquin River's tributaries include the Stanislaus River, Tuolumne River, Merced River, Calaveras River and Mokelumne River. They are perhaps the most heavily dammed and diverted rivers in the world.
The river originates at three locations. The South Fork begins at Martha Lake (Template:Coor dms) at an elevation of 11,004 feet (3354 m). The Middle Fork begins at Thousand Island Lake and joins the South Fork north of Balloon Dome in the Ansel Adams Wilderness. The North Fork, (a stream), begins at Twin Island Lakes and joins the Middle Fork east of Junction Butte Template:Coor dms. The river emerges from the foothills at what was once the town of Millerton, the location of Friant Dam since 1944, which forms Millerton Lake. The river passes through a narrow valley of which John Muir once said: "Certainly this Joaquin Canyon is the most remarkable in many ways of all I have entered."
The river flows west to the trough of the Central Valley, where it is joined by the Sierra's other great rivers and then flows north to the San Joaquin-Sacramento River Delta and then San Francisco Bay. Water from the river is used to irrigate 1,500 square miles of productive farmland on the east side of the Central Valley where 200 kinds of produce are raised from oranges to cotton. However due to water consumption which lets only 5% of historic levels into the riverbed, in most recent years the river doesn't reach its mouth but runs dry about 37 miles below Friant Dam. The Stockton Deep Water Channel makes the lower reach of the river navigable for ocean freighters as far inland as Stockton. However, sedimentation, particularly that caused by hydraulic mining has greatly reduced the San Joaquin River system's navigability.
Since the mid-19th century, the waters of the San Joaquin have been extensively manipulated and diverted for human use. Its primary uses are hydroelectricity production and water consumption, especially irrigation. It is a preferred source of drinking water, and it is used for groundwater recharge. As of 2005, the Metropolitan Water District which serves Los Angeles was negotiating a swap of San Joaquin water for less pure water from their reservoirs.
The river once supported the southernmost salmon run in North America. As a result of the water diversion and consumption, by 1928, the California Department of Fish and Game had issued a bulletin reporting that there were "very few" salmon remaining in the San Joaquin River above the Merced River and the "historical" salmon fishery that once existed had been "severely depleted." Although some sources claim that the river may have once supported large runs of both fall-run and spring-run Chinook salmon — up to 300,000 returning adults annually — these claims appear to be greatly exaggerated, given the river's hydrology, San Joaquin Valley temperatures, and the impacts of these factors on available fish habitat. An official with the California Department of Fish and Game stated in 1930s that the spawning gravels in the river were only sufficient to support, at most, about 15,000 returning fish. During that same time (late 1930s - early 1940s), the salmon counts taken by the California Department of Fish and Game at the Mendota Dam fish ladder showed about 3,000-7,000 salmon returning each year to spawn. Steelhead trout may have also been present in the river in the 19th century, although there is no known evidence to confirm this hypothesis. In 2004, a federal court ruled the U.S. Bureau of Reclamation in violation of state law for not letting enough water flow to maintain the historic salmon population.