The Pend Oreille River is a tributary of the Columbia River, approximately 130 miles long, in Northern Idaho and Northeastern Washington in the United States, as well as Southeastern British Columbia in Canada. In its passage through British Columbia its name is spelled Pend-d’Oreille. It drains a scenic area of the Rocky Mountains along the US-Canada border on the East side of the Columbia. The river is sometimes defined as the lower part of the Clark Fork, which rises in Western Montana. The river drains an area of 25,792 square miles mostly through the Clark Fork and its tributaries in Western Montana and including a portion of the Flathead River in Southeastern British Columbia. The full drainage basin of the river and its tributaries accounts for 43% of the entire Columbia River Basin above the confluence with the Columbia. The total area of the Pend Oreille basin is just under 10% of the entire 258,000 square mile Columbia River Basin.


There are two major watersheds in Pend Oreille County which include the Pend Oreille River and the Little Spokane River. Most of the land within Pend Oreille County drains into the Pend Oreille River and then into the Columbia River, one of the largest watersheds in the United States. The Little Spokane River’s headwaters are located at the Southern edge of the town of Newport. The Little Spokane River drains large portions of the southern areas of Pend Oreille and Stevens Counties and a large area of Northern Spokane County. The Little Spokane River flows into the Spokane River which then drains to the Columbia River which terminates along the Washington Oregon state borders at the Pacific Ocean. Awareness of conservation and natural resource concerns and issues along with the stewardship of all creeks, rivers, lakes and streams will have an impact on the health of downstream water bodies.


A sub-watershed is a watershed containing a system of smaller tributaries that drain into a larger watershed system. For example the following sub-watersheds drain into the Pend Oreille River: Calispel, Skookum, Tacoma, Sullivan, LeClerc, Upper and Lower West Branch Priest River and Granite Creeks. Each one of these larger creeks that make up their own sub-watershed will have several smaller tributaries that drain into them. These larger creeks with their small tributaries make up what is referred to as a sub-watershed.