Discover the 10 Longest Rivers in California

Written by Kellianne Matthews
Updated: May 29, 2022
Image Credit RMF/Shutterstock.com
Share this post on:

California is a state on the western coast of the United States of America. It is the largest state in the U.S. by population and the third-largest state by physical size. California stretches along the coast of the Pacific Ocean. The state has many drastically different landscapes and climates. Ranging from hot and dry deserts, alpine tundra, wet and rainy coastal forests, a volcanic plateau, high snowy mountains, and fertile farmland.

What kinds of rivers flow through such a dynamic landscape? What do they look like? How big are they? Let’s look at the 10 longest rivers in California!

Rivers in California

A river is basically a flowing source of water that drains into a bigger body

Jaros/Shutterstock.com

California has 189,454 miles of river. A river is defined as a moving body of water that flows into a larger body of water, like a lake, sea, or ocean. That definition is a bit vague, but that’s because rivers come in so many shapes and sizes. Some rivers are extremely large, some wide, some skinny. Some rivers flow above ground, and some rivers even flow below ground! What all rivers seem to have in common is that they are constantly moving, providing water to all kinds of ecosystems and wildlife as they pass through. California is home to many of these pretty spectacular rivers.

As we look at the largest rivers in California, we will be measuring their size based on length, rather than depth or discharge amounts. So, what are the 10 largest and longest rivers in the state of California?

10. Kern River – 165 miles

Longest Rivers in California - Kern River
The Kern River is the native range for California’s State Fish, the California golden trout.

zippy/Shutterstock.com

The Kern River is 165 miles long and passes through many beautiful canyons and rock formations.  It is a popular place for whitewater rafting, kayaking, fishing, and wilderness hiking. 151 miles of the Kern River is designated as a “Wild and Scenic River.”

The Kern River’s watershed is the native range of the California golden trout, which is California’s State Freshwater Fish. In fact, all three members of the “Golden Trout Complex” live in the Kern River: the California golden trout, the Little Kern golden trout, and the Kern River rainbow trout. The California golden beaver also lives in and around the Kern River.

9.      Salinas River – 175 miles

woodchuck vs beaver
The Salinas River is home to the California golden beaver.

Chase Dekker/Shutterstock.com

The Salinas River originates in the Los Machos Hills of the Los Padres National Forest. It flows for 175 miles until it eventually connects with Monterey Bay and the Pacific Ocean. Sometimes the Salinas River can be dry and shallow above ground since much of the water flows underground. The Salinas River is the primary water source for vineyards and farms in the valley. In fact, irrigation in the Salinas valley makes it one of the most productive agricultural areas in California. This area is especially known for growing lettuce and artichokes.

In the 19th-century fur trappers reduced the beaver population in the area surrounding the Salinas River. However, the California golden beaver bounced back and now has even expanded its home range. The Salinas River is also a wildlife corridor. This means that it acts as a passage where wildlife can move around human activities and structures and connect to one another. 

8.      Owens River – 183 miles

Longest Lakes in California - Owens River
The headwaters of the Owens River is a popular location for anglers and fishermen.

RMF/Shutterstock.com

The Owens River is 183 miles long in eastern California. It starts in the Sierra Nevada Mountains in southwestern Mono County and empties into Owens Lake. Owens River is one of the four desert rivers in California. Owens River was rerouted to provide water to Los Angeles during the California Water Wars in the early 1900s. Because of this, much of the Owens Valley and Owens Lake dried up.

7.      Amargosa River – 185 miles

Longest Rivers in California - Amargosa River
The Amargosa River drains into Death Valley.

rawaccess/Shutterstock.com

The Amargosa River is unique because it flows above ground only after cloudbursts and flash floods. Most of the time the river flows underground, except for a few select sections. One section where the Amargosa River flows above ground is in the Amargosa Canyon. Here the river passes through the Amargosa River Natural Area and provides water for a lush area of vegetation and abundant wildlife.

The entire Amargosa River—above ground and below ground—is 185 miles long. The name of the Amargosa River comes from the Spanish word amargo which means “bitter”, likely from agua amargosa, meaning “bitter water.”

6.      Eel River – 196 miles

Longest Rivers in California - Eel River
The Eel River’s ecology is continually affected by human activities like road-building, logging, and the cannabis industry.

Anna Westman/Shutterstock.com

The Eel River begins on the southern flank of Bald Mountain in Mendocino National Forest. It then flows for 196 miles until it empties into the Pacific Ocean. There are no eels in the Eel River, despite its name. In fact, the Eel River gets its name from an eel-shaped parasitic fish, the Pacific lamprey. Unlike true eels, Pacific lampreys live in the Eel River.

There are 15 different fish species in the Eel River, including the Sacramento sucker, Pacific staghorn sculpin, prickly sculpin, Coastrange sculpin, and threespine stickleback. The Eel River is also home to many aquatic mammals like beavers, minks, raccoons, muskrats, and river otters. Human development and the construction of dams hurt much of the natural habitat here. In 1981 the Eel River was declared a Wild and Scenic River, limiting the construction of new dams.

5.      Pit River -207 miles

Longest Rivers in California - Pit River
The Pit River gets its name from the Pit River American Indian Tribe. The Pit River Tribe hunted for game along the river using pit traps.

Gibson Outdoor Photo/Shutterstock.com

The Pit River is the longest tributary of the Sacramento River, measuring 207 miles long. It begins in the northeastern corner of California and eventually joins the Sacramento River in the Central Valley. Its journey passes through both the Modoc National Forest and the Shasta National Forest. The Pit River is used for irrigation, hydroelectricity, and conservation purposes. It is also a popular destination for fishing, fly fishing, and rafting.

4.      Klamath River – 257 miles

Largest salmon - chinook salmon
The Klamath River is an important river for anadromous fish like Chinook salmon.

Kevin Cass/Shutterstock.com

The Klamath River is 257 miles long, flowing through Oregon and northern California on its way to the Pacific Ocean. It is the most important river south of the Columbia River for anadromous fish migration. Anadromous fish live in salt water, but travel to freshwater to breed. There are fish like Chinook salmon, rainbow trout, and steelhead trout, and coho salmon. In fact, the Klamath River is a prime habitat for coho salmon, which are a threatened species.

The Klamath River is also a popular location for sport fishing, kayaking, and whitewater rafting. Unfortunately, mines from the California Gold Rush as well as dams and diversions have caused a lot of water quality issues. However, many environmental groups and native tribes have been working together to enact change and help restore the water and surrounding natural habitat.

3.      San Joaquin River – 366 miles

Longest River in California - Joaquin River Delta
The San Joaquin River delta. The river is a wildlife corridor, providing passage around human activity for many species of wildlife.

Jeffrey T. Kreulen/Shutterstock.com

The San Joaquin River is 366 miles long. It begins in the high Sierra Nevada Mountain Range and eventually flowing into Suisun Bay, San Francisco Bay, and the Pacific Ocean. The San Joaquin River is one of the most important sources of irrigation water in California. It is also one of the most heavily dammed and diverted rivers in California.

The San Joaquin River was once home to hundreds of thousands of migratory fish and birds. Historical accounts explain how there were times when there were so many birds that they would block out the sun in the sky and sounded as loud as a freight train.

Engineering development and human activity has now replaced and altered over 95% of the historical wetlands in the San Joaquin River. However, part of the San Joaquin River is now a National Wildlife Refuge. It is also an important wildlife corridor, helping animals pass through and around human activity.

2.      Sacramento River – 400 miles

Longest Rivers in California - Sacramento River
The Sacramento River provides a habitat for many endangered species.

Teri L Wertman/Shutterstock.com

The Sacramento River is the longest river that is contained entirely within the state of California (it does not cross over into any other state). It is 400 miles long and was once called “the Nile of the West.” Today, it is a popular location for kayaking, motorboating, fishing, hunting, tubing, swimming, birding, wildlife observation, and hiking. The river begins in the Klamath Mountains and eventually flows to the Sacramento-San Joaquin River Delta and San Francisco Bay.

The Sacramento River provides a habitat for 40-60 species of fish and 218 species of birds. Many endemic amphibian and fish species are only found in and around the Sacramento River. Occasionally even marine animals make their way upriver, like whales and sea lions. The marine mammals usually are lost, or are looking for food or refuge.

Unfortunately, the wildlife here suffers from a lot of habitat loss due to the agricultural and urban development of the Sacramento River. Many of these animals are now considered endangered. Endangered species found in and around the Sacrament River include the western spadefoot, foothill yellow-legged frog, warbling vireo, least Bell’s vireo, southwestern willow flycatcher, and the western yellow-billed cuckoo.

1.      Colorado River – 1,450 miles

The Colorado River helped carve the Grand Canyon

Markue/Shutterstock.com

The Colorado River is the longest river that passes through California. Beginning in the central Rocky Mountains in Colorado, the Colorado River flows through seven states: Wyoming, Colorado, Utah, New Mexico, Nevada, Arizona, and California. The Colorado River also runs through the Grand Canyon, as well as eleven different U.S. National Parks.

The Colorado River is home to 40 species of fish, many of which are unique to this river, like the razorback sucker, bonytail chub, Colorado pikeminnow, and the humpback chub. These fish are currently at risk due to habitat loss and water diversion through dams, thermoelectric power stations, and evaporation.

Share this post on:
About the Author

Kellianne Matthews is a writer and editor with passion and expertise in animal behavior and ecology. She has an MA in Comparative Studies and researches human-animal studies, ecocriticism, film, and Interdisciplinary Humanities. Kellianne is unashamed to be a total research nerd and enjoys making new connections across disciplines. She loves reading, movies, her cats, and exploring the beautiful diversity of the world.

More from A-Z Animals