America’s Most Endangered Rivers for 2014: San Joaquin River


Threat: Outdated water management and excessive diversions
At risk: River health and resilient communities

San Joaquin, CA | © Alison Jones

San Joaquin, CA | © Alison Jones,

The San Joaquin is Central California’s largest river, supporting endangered fish and wildlife, communities, and one of the most productive agricultural regions in the world. However, the river is so overtapped that it runs completely dry in stretches, threatening water quality, endangering fish and wildlife, creating uncertainty for farmers, and leaving communities vulnerable in the face of more frequent and severe droughts. The California Water Resources Control Board must act this year to increase flows in the San Joaquin so that the watershed is healthy enough to support fish and wildlife, sustainable agriculture, and resilient communities for generations to come.

The River

The San Joaquin River and its principal tributaries— the Merced, the Tuolumne, and the Stanislaus— originate on the high slopes of the southern Sierra Nevada, and flow through the fertile San Joaquin Valley south of Sacramento. For millennia, the cool waters of these rivers sustained the southernmost runs of king salmon and vast wetlands that supported millions of waterfowl, herds of tule elk, and even grizzly bear.

Today, approximately four million people live in the San Joaquin watershed. These rivers support some of the most productive and profitable agriculture in the world, irrigating more than two million acres of arid land. The rivers also generate over 3,000 megawatts of hydropower, provide drinking water to over 4.5 million people (including the City of San Francisco), and support numerous endangered or declining species. From the headwaters, including Yosemite National Park, to the mouth at the San Francisco Bay-Delta estuary, these rivers support a thriving recreational industry that generates hundreds of millions in economic activity and includes world class whitewater rafting, bass tournaments, waterfowl hunting, and a native rainbow trout fishery.

The Threat

San Joaquin, CA river diversions outside Stockton | © Sarah Craig

Outdated water management and excessive diversions are threatening the health of the San Joaquin River | © Sarah Craig

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Years of managing the San Joaquin for agriculture, hydropower, and flood control have taken their toll on the river. Dams, levees, and excessive water diversions have hurt river habitat and opportunities for recreation and community access. Over one hundred miles of the mainstem river have been dry for over fifty years, and water diversions along the tributaries take more than 70 percent of the natural flow. The river’s salmon and steelhead populations are on the brink of extinction. Excessive diversions, groundwater overdraft, and unsustainable water management have also made communities vulnerable to increasingly frequent and severe droughts.

The present drought places additional stress on the river and its communities, but we must not allow the drought to force rash decisions— like cutting environmental protections— that will harm the river, fish and wildlife, and communities for years to come.

What Must Be Done

The current drought underscores the need to take long-overdue action to restore the San Joaquin River. We must plan for a more sustainable future that includes both a healthy river and sustainable agriculture.

The California State Water Resources Control Board, the agency charged with allocating water rights and protecting water quality, is developing a plan for management of the river. The Board must act to increase flows in the river to protect water quality, fish, recreation, and community access, and support sustainable agriculture.

Additionally, Congress must oppose all efforts to overturn state and federal water laws designed to protect the environment, which would further dry up the San Joaquin River.