[4] It drains into and through the Owens Valley, an arid basin between the eastern slope of the Sierra Nevada and the western faces of the Inyo and White Mountains.

It flows south-southeast through the Owens Valley between the Sierra Nevada on the west and the White and Inyo Mountains on the east, past Big Pine.

[15][16] Further to the north, the Owens River basin encompasses predominantly igneous rocks and vast remnants of past volcanic activity.

[18] Mammoth Mountain, to the southwest (more popularly known as a major ski area) also formed from eruptions related to the Long Valley Caldera.

[11] To the north of the Caldera, extending to the Mono Lake area, lie the chain of Mono-Inyo Craters, which range in age from 400,000 to 500 years old.

[19] During the Pleistocene at the end of the last glacial period, melting glaciers in the Sierra Nevada and Inyo/White Mountains fed prodigious amounts of runoff into the Owens River, causing it to expand to many times its current size.

The increased river volume caused Owens Lake to rise as well, eventually spilling out the south side of the valley into the Mojave Desert.

[20] During this relatively short time, the Owens River became part of a vast interior drainage system that stretched east to west, covering over 8,000 square miles (21,000 km2).

[22] In the upper Owens Valley lie traces of some of California's first irrigation systems, created by Paiute groups to water small patches of crops.

It is believed that native people in the upper portion of the valley once built dams across the Owens River (and possibly one of its major tributaries, Bishop Creek) to divert water into local canals.

[23] Typically, the Native Americans built dams across the river or other tributary streams in the spring out of materials including boulders, dirt, reeds, grass, or other elements.

[33] Supporting this line of evidence, Tappe records in 1941 an eyewitness who said beaver were plentiful on the upper part of the Carson River and its tributaries in Alpine County until 1892 when they fell victim to heavy trapping.

[35] This decision runs counter to an independent assessment commissioned by LADWP and the Inyo County Water Department in 1997, where it was recommended that beaver be maintained in reasonable populations and their dams left in place because "Although beaver activity has resulted in the removal of much willow and other shrub and woody vegetation and the dams create favorable tule conditions and reduce fish spawning habitat, they also provide important fish rearing habitat, mesic meadows, and promote the growth of other riparian species.

"[36] The acquisition of water rights for the Los Angeles Aqueduct under the direction of William Mulholland was highly controversial and led to violence and sabotage by local residents in the 1920s.