San Joaquin River: Exploring California’s Gem

For decades, a 60-mile stretch of the San Joaquin River ran completely dry — not low, not seasonal, but dry riverbed — after Friant Dam diverted nearly all of its water to farms and cities starting in the 1940s. That’s changed in the last 15 years through one of the largest river restoration efforts in the country, and understanding that history is central to understanding what the river actually is today, not just its scenery.

The Basics

The San Joaquin River runs 366 miles from its headwaters in the Sierra Nevada to the Sacramento-San Joaquin Delta, making it California’s second-longest river after the Sacramento. It flows west out of the mountains, turns north through the Central Valley, and eventually joins the Sacramento River in the Delta before reaching San Francisco Bay. Its major tributaries — the Merced, Tuolumne, Stanislaus, and Mokelumne rivers — all feed into it from the Sierra Nevada foothills.

The river’s watershed, at roughly 31,800 square miles, is the largest single river basin entirely within California.

What Happened to the River (and Why It Matters Now)

Friant Dam, completed in 1942 northeast of Fresno, was built to supply irrigation water to Central Valley farms via the Friant-Kern and Madera canals. It worked as intended for agriculture, but it also dried up roughly 60 miles of the river below the dam for most of the year and wiped out what had been the largest spring-run Chinook salmon population in the continental U.S. — a run that once numbered in the hundreds of thousands of fish annually.

In 1988, environmental groups sued the federal government over the dried-up river, arguing it violated California law requiring dam operators to maintain enough flow to keep downstream fish in good condition. The case ended in a landmark 2006 settlement that created the San Joaquin River Restoration Program, a nearly $1 billion, multi-agency effort covering 150–152 miles of river from Friant Dam down to the river’s confluence with the Merced River. The program has two explicit goals: restore self-sustaining salmon populations, and do it without significantly cutting into the water supply that Central Valley farms depend on — a genuinely difficult balancing act that has drawn criticism from both environmental groups (who argue the restored flows are still too limited) and agricultural interests (concerned about water supply impacts).

Interim water releases from Friant Dam began in 2009, and the program has released juvenile spring-run Chinook salmon into the river since 2014, after the run had been locally extinct there for more than 60 years. In low-water years, migrating adult salmon still can’t make it past certain diversion structures on their own, so field crews net them and truck them upstream in water tanks. The program has shown real results: in 2025, a record 448 adult spring-run Chinook returned from the ocean to spawn in the river, the strongest return since the reintroduction effort began.

Where to Actually Experience the River

The San Joaquin River Parkway, run by the San Joaquin River Parkway and Conservation Trust since 1988, is the most accessible way to spend time on the river without a boat. The Trust has permanently protected over 4,100 of a planned 6,500 acres along the river near Fresno, with a growing multi-use trail system for hiking and biking. It’s a genuinely useful, ongoing project rather than a finished attraction, so check the Trust’s current trail map before visiting, since sections continue to open as land acquisition and restoration work progress.

Fishing is legal on much of the river, but California Department of Fish and Wildlife regulations around the restoration area specifically protect spring-run Chinook salmon — if you’re fishing anywhere near Friant Dam or the restoration reach, check current CDFW regulations for that specific stretch before you go, since rules here are stricter than on unrestricted sections of the river given the salmon reintroduction effort underway.

The river also supports several National Wildlife Refuges in its lower reaches, including the San Joaquin River National Wildlife Refuge, which protect wetland habitat for waterfowl and other wildlife along the valley floor.

Bottom Line

The San Joaquin River today is best understood as a river actively being rebuilt, not a finished natural landmark — the restoration program below Friant Dam is ongoing, dependent on snowpack and runoff each year, and still adjusting as agencies learn what works. If you want to see the restoration in action, the stretch below Friant Dam (Reach 1A) is the area to focus on; if you want recreation and trails, the San Joaquin River Parkway near Fresno is the most developed public access point. Either way, check current conditions and any fishing restrictions directly before visiting, since both the water flows and the regulations shift from year to year based on the restoration program’s status.