On average , the 40 - mile ( 64 km ) long creek contributes about a third of the lower Siuslaw 's water volume .
Lake Creek is a major tributary of the Siuslaw River in Lane County in the U.S. state of Oregon .
On average , the 40 - mile ( 64 km ) long creek contributes about a third of the lower Siuslaw River 's water volume .
Lake Creek is a major tributary of the Siuslaw River in Lane County in the U.S. state of Oregon .