River · United States
San Joaquin River
The San Joaquin River is the second-longest river in California. It rushes down from the high Sierra Nevada, flows through the farmland of the San Joaquin Valley and ends in a large delta together with the Sacramento River.
Picture credit: MCalamari (Public domain) · Richard E. Ellis (CC BY 3.0) · Wikimedia Commons
Where is San Joaquin River?
The river starts here: Thousand Island Lake, Ansel Adams Wilderness, Sierra Nevada.
It ends in the Sacramento–San Joaquin River Delta and Suisun Bay, California.
Countries on the river: the United States.
The story behind it
The San Joaquin begins in mountain lakes more than 3 700 metres high. By the time it reaches the foothills, it is only about 180 metres above the sea. Long ago it flowed through grasslands and wide marshes, where tule elk and pronghorn grazed. The Yokuts people called it Tihshachu, which means ‘salmon-spearing place’, and the river once had the third-largest salmon run in California. Then Friant Dam was finished in 1942, and most of the water was sent into canals. The valley now grows more than 200 different crops, but a stretch of the river about 240 kilometres long often runs dry. Since 2009, extra water has been let out of the dam again to help the river and bring the salmon back. In the north, big ships reach the port of Stockton through a deep channel.
Questions children ask
How long is the San Joaquin River?
The San Joaquin River is about 589 km long. Depending on how it is measured, some sources give a little less, about 560 km.
Why does the San Joaquin River sometimes run dry?
Most of its water is taken out and sent into canals and aqueducts. That is why a stretch of about 240 km often has no water at all.
Are there salmon in the San Joaquin River?
Long ago the river had the third-largest salmon run in California. Since 2009, extra water has been let out of Friant Dam so that salmon can come back.
Where these numbers come from
Every figure on this page was checked against public reference sources before publication. Where sources genuinely disagree, the text says so.
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