The Smith River is a 90-mile (140 km) tributary of the Umpqua River in the U.S. state of Oregon. It drains 352 square miles (910 km2) of the Central Oregon Coast Range between the watershed of the Umpqua to the south and the Siuslaw River to the north.
Rising in northern Douglas County about 10 miles (16 km) north of Drain, the river flows generally west in a winding course through the mountains, passing through the Siuslaw National Forest for about 10 miles (16 km) in its lower course. It joins the Umpqua from the north across from Reedsport, about 6 miles (10 km) from the mouth of the Umpqua on the Pacific Ocean.
