San Joaquin River - Economics

River in C California, USA, in the S part of the Central Valley; rises in the Sierra Nevada; joins the Sacramento R just above Suisin Bay; 510 km/317 mi long; major tributaries the Fresno, Merced, Mariposa; connected with the Sacramento R in the Central Valley Project to increase irrigation, flood-control, and hydroelectricity.

San Joaquin River
Origin	Martha Lake (California)
Mouth	Sacramento-San Joaquin Delta
Basin countries	United States (100%)
Length	530 km (330 mi)
Source elevation	3,354 m (11,004 ft)
Avg. km² (32,000 mi²)

The San Joaquin River (pronounced /'sæn wɑ'kin/), 330 miles (530 km) long, is the second-longest river in California, United States. The San Joaquin and its eight major tributaries drain about 32,000 square miles (83,000 km²) of California's San Joaquin Valley. The San Joaquin River's tributaries include the Stanislaus River, Tuolumne River, Merced River, Calaveras River and Mokelumne River.

Tributaries / canals / lakes

The river flows west to the trough of the Central Valley, where it is joined by the Sierra's other great rivers and then at Mendota Pool flows north to the Sacramento-San Joaquin Delta and then San Francisco Bay. With the exception of overflow and drain water along the North Fork of the Kings River, which meets the San Joaquin River at Mendota Pool, the San Joaquin River itself is the southern most river of the greater San Joaquin River watershed.

During some years, portions of the San Joaquin River (and some of its tributaries) will run dry as water is diverted from the river for urban or agricultural use. In other places, such as at the confluence of the San Joaquin and Chowchilla Rivers near Dos Palos, California, the entire river has been diverted to man-made bypass channels, such as the Eastside Bypass.

The following rivers are tributaries to the San Joaquin River:

Mokelumne River Cosumnes River Calaveras River Stanislaus River Tuolumne River Merced River Bear Creek Chowchilla River Ash Slough Berenda Slough Fresno River Kings River, North Fork

The following lakes and reservoirs are on the San Joaquin River watershed:

Pardee Reservoir Camanche Reservoir New Hogan Reservoir New Don Pedro Reservoir Lake McClure Eastman Lake Hensley Lake Mendota Pool Millerton Lake Pine Flat Reservoir Lake Kaweah Lake Success

The following artificial canals are part of the San Joaquin River system:

Stockton Deep Water Ship Channel Grant Line Canal Eastside Bypass Chowchilla Bypass San Luis Drain Madera Canal Friant Kern Canal

Confluence / destination

The San Joaquin River meets the Sacramento River near the city of Antioch. Before meeting the Sacramento River, the San Joaquin River has two distributary rivers, the Old River and the Middle River, both of which once were the main channels of the river. Due to the bend in the San Joaquin River channel at the head of the Old River, a significant portion of the San Joaquin River flow continues down the Old River instead of heading northward along the San Joaquin. This flow split causes problems for outmigrating salmon, as the flows along the Old River are eventually divided between the Old River, Middle River, and Grant Line Canal. In response to this problem, the California Department of Water Resources and California Department of Fish and Game construct and manage temporary rock barriers at the head of the Old River in order to keep fish in the main channel of the San Joaquin River.

Historically, the native habitat of the endangered San Joaquin Kit Fox included the riparian zone near the San Joaquin River.

Prior to the completion of Friant Dam in 1942, the San Joaquin River had the distinction of being the southern most habitat for salmon in the United States. However, the diversion of water from the upper reaches of the San Joaquin River and its tributaries significantly reduced the number of Chinook Salmon native to the river.

Economics

Navigation

Sedimentation has greatly reduced the San Joaquin River system's navigability. The abrupt geometry change from the shallow river channel upstream of Stockton to the deep Ship Channel itself is believed to contribute to the low dissolved oxygen concentrations in the river near the DWSC. As contemplated by the Central Valley Project Act, most of the waters of the San Joaquin River are diverted into canals so that the river remains dry for a 17 mile (27 km) stretch between Gravelly Ford and the Mendota Pool except when flood control requires additional releases from the dam.

The San Joaquin river once supported the southernmost salmon run in North America. As a result of seasonal water diversions and the operation of upstream hydropower reservoirs, 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 salmon habitat.

Timeline

Year	Event(s)
1858	Miller and Lux begin acquiring riparian lands along the San Joaquin and Kings Rivers
1912	Southern Edison begins building reservoirs, dams, & powerhouses on upper San Joaquin River
1951	Delta-Mendota Canal imports water to the west side of the San Joaquin Valley, including the San Joaquin River Water Authority Exchange Contractors
1997	A 3-day storm that began Jan. 1, 1997 resulted in significant flooding in California, including along the San Joaquin