Oroville Dam is an earthfill embankment dam on the Feather River east of the city of Oroville, California, in the Sierra Nevada foothills east of the Sacramento Valley. At 770 feet (235 m) high, it is the tallest dam in the U.S. and serves mainly for water supply, hydroelectricity generation, and flood control. The dam impounds Lake Oroville, the second-largest reservoir in California, capable of storing more than 3.5 million acre-feet (1.1×10^12 US gal; 4.3×109 m3).
Oroville Dam
Oroville Dam spillway damage, February 27, 2017
Water overflowed the parking lot past the emergency spillway (in the background), while water continued to flow through the main spillway (in the foreground), on February 11.
Water from the Oroville Dam flows over the emergency spillway on Sunday, February 12
The Feather River is the principal tributary of the Sacramento River, in the Sacramento Valley of Northern California. The river's main stem is about 73 miles (117 km) long. Its length to its most distant headwater tributary is just over 210 miles (340 km). The main stem Feather River begins in Lake Oroville, where its four long tributary forks join—the South Fork, Middle Fork, North Fork, and West Branch Feather Rivers. These and other tributaries drain part of the northern Sierra Nevada, and the extreme southern Cascades, as well as a small portion of the Sacramento Valley. The total drainage basin is about 6,200 square miles (16,000 km2), with approximately 3,604 square miles (9,330 km2) above Lake Oroville.
The Feather River near its confluence with the Bear River
Buzzard Springs, partial source of the North Fork Feather River, near Rice Creek and with Lassen Peak in the background
Frazier Creek Falls in Plumas National Forest is part of the Middle Fork watershed
Aerial view of the region of the confluence of the Feather and Yuba rivers at Marysville and Yuba City