Lochsa River

The Lochsa River is in the northwestern United States, in the mountains of north central Idaho. It is one of two primary tributaries (with the Selway to the south) of the Middle Fork of the Clearwater River in the Clearwater National Forest. Lochsa is a Nez Perce word meaning rough water. The Salish name is Ep Smɫí, "It Has Salmon."

The Lochsa (pronounced "lock-saw") was included by the U.S. Congress in 1968 as part of the National Wild and Scenic Rivers Act. The Lochsa and Selway rivers and their tributaries have no dams, and their flow is unregulated. In late spring, mid-May to mid-June, the Lochsa River is rated as one of the world's best for continuous whitewater.

The main stem of the Lochsa is 70 miles (113 km) long from its headwaters near Powell Ranger Station in the Bitterroots to Lowell, Idaho, where the Lochsa joins the Selway River to form the Middle Fork of the Clearwater. Over this distance, the river drops nearly 2,000 feet (610 m) from 3,441 feet (1,049 m) above sea level at Powell to 1,453 feet (443 m) at Lowell.