Pit River, CA

The Pit River or Pitt River is a major river draining northeastern California into the state's Central Valley. The Pit, the Klamath and the Columbia are the only three rivers in the U.S. that cross the Cascade Range.

The longest tributary of the Sacramento River, it contributes as much as eighty percent of their combined water volume into Lake Shasta; the junction of their Lake Shasta arms is 4 miles (6.4 km) miles northeast of Shasta Dam. The Pit River is approximately 315 miles (507 km) long measuring from its longest source.
The Pit River drains a sparsely-populated volcanic highlands area, passing through the south end of the Cascade Range in a deep canyon northeast of Redding.

The Pit River rises in several forks in Modoc and Lassen counties in the northeastern corner of California in the Warner Mountains. The 58-mile (93 km) South Fork Pit River - West Valley Creek - Cedar Creek source originates just southeast of Buck Mountain in the Warner Mountains in the extreme southeastern corner of the Modoc National Forest 9 miles (14 km) west of the Nevada border. The South Fork is formed from the confluence of several creeks in Jess Valley 13 miles (21 km) northeast of Madeline and flows west through a narrow canyon, past Likely, then generally through a broad ranching valley where its waters are diverted for irrigation and waterfowl conservation in an extensive system of canals. The 30-mile (48 km) long North Fork - Linnville Creek tributary begins 5 miles (8.0 km) southeast of the town of Davis Creek. It flows generally south-southwest, joining the South Fork from the north near Alturas.

The combined river flows west-southwest in a winding course across Modoc County, past Canby and through the Modoc National Forest in the narrow Stonecoal Valley gorge. It turns south to flow past Lookout and into northern Lassen County, past Bieber to emerge into the ranching region of Big Valley. North of Little Valley it runs east into northeastern Shasta County, passing through the Cascades in a serpentine canyon in the Shasta National Forest. It flows past Pittville, McArthur, and Fall River Mills to join the Sacramento River as the eastern arm of Shasta Lake reservoir, approximately 15 mi (24 km) north of Redding. The lower 30 mi (50 km) of the river forms the longest of the five arms of Lake Shasta, which is formed by Shasta Dam on the Sacramento downstream from the original confluence.

Goose Lake was once the source of the North Fork Pit River, but it now usually an enclosed basin by terms of surface water. During rare high water levels, the lake spills out into the Pit River system.