The Lower Columbia River Chinook ESU includes all populations of chinook salmon in the Columbia River and its tributaries in Washington and Oregon, from the mouth of the Columbia up to and including the Big White Salmon and Hood Rivers. It also includes the Willamette River to Willamette Falls.
The State of Oregon only monitors populations occurring in Oregon. There are nine recognized populations of fall chinook in the Lower Columbia ESU, all of which are considered to be functionally independent. However, at this time data are only available for the Hood River population.