Sierra Nevada (U.S.) - Geography

Geography

The Sierra Nevada stretches from the Susan River and Fredonyer Pass in the north to Tehachapi Pass in the south. It is bounded on the west by California's Central Valley and on the east by the Basin and Range Province. Physiographically, the Sierra is a section of the Cascade-Sierra Mountains province, which in turn is part of the larger Pacific Mountain System physiographic division.

West-to-east, the Sierra Nevada's elevation increases gradually from the California Central Valley to the crest, while the east slope forms the steep Sierra Escarpment. The range is drained on its north-west slopes by the Sacramento River and to the west-southwest by the San Joaquin River, two major Central Valley watercourses that ultimately discharge to the Pacific Ocean. Smaller rivers of the west slope include the Feather, Yuba, American, Mokelumne, Stanislaus and Tuolumne. The southern part of the mountains are drained by four rivers called the Kings, Kaweah, Tule, and Kern. These rivers flow into an endorheic basin called Tulare Lake, but historically joined the San Joaquin during wet years.

To the east, the melting snow of the mountains forms many small rivers that flow out into the Great Basin of Nevada and eastern California. From north to south, the Susan River flows into intermittent Honey Lake; the Truckee River flows from massive Lake Tahoe into Pyramid Lake; the Carson River runs into Carson Sink; the Walker River into Walker Lake; Rush, Lee Vining and Mill Creeks into Mono Lake; and the Owens River into the dry Owens Lake. None of the east-side rivers reach the sea; however, many of the streams from Mono Lake southwards are diverted into the Los Angeles Aqueduct and their water shipped to Southern California.

The height of the mountains in the Sierra Nevada increases gradually from north to south. Between Fredonyer Pass and Lake Tahoe, the peaks range from 5,000 feet (1,500 m) to more than 9,000 feet (2,700 m). The crest near Lake Tahoe is roughly 9,000 feet (2,700 m) high, with several peaks approaching the height of Freel Peak . Further south, the highest peak in Yosemite National Park is Mount Lyell . The Sierra rise to almost 14,000 feet (4,300 m) with Mount Humphreys near Bishop, California. Finally, near Independence, Mount Whitney is at 14,505 feet (4,421 m), the highest point in the contiguous United States.

South of Mount Whitney, the range quickly dwindles. The crest elevation is almost 10,000 feet (3,000 m) near Lake Isabella, but south of the lake, the peaks reach only to a modest 8,000 feet (2,400 m).