Metolius River, OR

The Metolius River is a tributary of Lake Billy Chinook in Central Oregon, United States, near the city of Sisters. The river flows north from springs near Black Butte, then turns sharply east, descending through a series of gorges before ending in the western end of the lake. The unincorporated community of Camp Sherman lies astride the southern end of the river. The river's drainage basin is 315 square miles (820 km2) in area and, according to at least one estimate, contains 110 miles (180 km) of perennial streams, 324 miles (521 km) of intermittent streams, 42 lakes, and 121 ponds.

The headwaters of the river are at Metolius Springs, where the river emerges from two clusters of springs, about 300 feet (91 m) apart. The springs are at the base of Black Butte. Water flows to these springs from the drainage basin around Black Butte Ranch, several miles to the south. The elevation of the drainage basin is 300 feet (91 m) above that of the springs, forming a natural standpipe that tends stabilize the river's rate of flow.

As a consequence, the water level in the Metolius River is relatively constant. The rate of flow at the headwaters is approximately 190 m³/min (6,700 ft³/min or 50,000 gallons per minute), although it grows by an additional 2,300 m³/min (80,000 ft³/min or 600,000 gallons per minute) by the time the river reaches Lake Billy Chinook. Similarly, the water temperature is also stable; at the river source, the water temperature is a consistent 48 °F (8.9 °C).  Water temperatures tend to fluctuate between 39 and 54ºF.

The river flows 28.6 miles (46.0 km) from Metolius Springs through the Deschutes National Forest, emptying into Lake Billy Chinook and ultimately the Deschutes River. The upper 11.5 miles (18.5 km) of the river is a popular destination for catch-and-release fishing, whitewater rafting, picnicking, and camping. The lower 17 miles (27 km) is on the boundary of the Warm Springs Indian Reservation, and is "a primitive area where motorized vehicles are not allowed."

Sport fishing on the Metolius River is catch-and-release, fly-fishing only (barbless hook), on the accessible, upper portion of the river, and includes rainbow trout, whitefish, bull trout and kokanee salmon.