Big River (California)

Big River
river
Big River, from the Big River Unit of Mendocino Headlands State Park.
Country	United States
State	California
Region	Mendocino County
Source	Impassable Rocks
- location	7 mi (11 km) south of Willits, California
- coordinates	39°19′3″N 123°22′23″W / 39.31750°N 123.37306°W / 39.31750; -123.37306
Mouth	Pacific Ocean
- location	Mendocino, California
- elevation	0 ft (0 m)
- coordinates	39°18′8″N 123°47′41″W / 39.30222°N 123.79472°W / 39.30222; -123.79472Coordinates: 39°18′8″N 123°47′41″W / 39.30222°N 123.79472°W / 39.30222; -123.79472
Basin	181 sq mi (469 km2)

The Big River is a 41.7-mile-long (67.1 km)river in Mendocino County, California, draining an area of about 181 square miles (470 km²). The Big River watershed borders the watersheds of the Noyo River to the north, the Eel River and Russian River to the east, and the Little River, Albion River, and Navarro River to the south.

The river's headwaters are thirty miles inland from the Pacific Ocean in the Mendocino Range, part of the California Coast Range. The headwater area of the river is fed by Montgomery Creek as it flows through the upland riparian habitat and virgin redwoods of Montgomery Woods State Reserve. From there, the river flows roughly west through Jackson Demonstration State Forest. The lower portions of the river pass through Mendocino Woodlands State Park and the Big River Unit of Mendocino Headlands State Park before reaching the mouth of the river at the Pacific Ocean just south of the town of Mendocino.

The Big River is fed by precipitation, 90 percent of which falls between October and April, and which averages 40 inches (1,000 mm) per year at Fort Bragg near the coast and 51 inches (1,300 mm) at Willits inland. Winter weather is characterized by low intensity rain. The summers are dry and cool, with coastal fog. The river provides recreation and groundwater recharge for agricultural and industrial water supply for the community of Mendocino, California.