Habitat

Bridge across the Lower Columbia River

Habitat project accomplishments in lower Columbia

In the lower Columbia, salmon and steelhead inhabit nearly 2,300 river miles throughout 17 subbasins and the estuary. It is estimated that the habitat has declined anywhere from 30-90 percent. While restoration of all lost habitat is neither practical nor necessary, success in recovering our salmon runs will require both restoring degraded habitat as well as protecting functioning habitat.

Estimated loss of habitat in the Lower Columbia tributaries and estuary

The most common impacts to habitat conditions are:

  • Dams that require regulated stream flow
  • Blocked passage due to failing culverts, tide gates, and other barriers
  • Seasonal variations in high and low flows affecting water quality and temperature
  • Loss of channel stability and migration corridors
  • Limited off channel spawning and rearing areas
  • Loss of habitat complexity that provides protection from predators
  • Loss of nutrients that support juvenile survival

This information forms the basis for identifying priority protection and restoration needs. Referred to as Tier 1 and 2 reaches, these 575 highest priority reaches encompass 675 river miles and are the primary focus of restoration work. To date, lower Columbia sponsors have implemented more than 2,700 projects using a variety of funding sources.

Indicator data

Habitat Projects

For more information about habitat project actions, visit the Lower Columbia Fish Recovery Board’s SalmonPORT.

For more information about habitat project actions, visit the Recreation and Conservation Office’s Habitat Work Schedule and Project Search public databases.

Visit How we measure for background about this data, and our Salmon Data Portal for original source data behind the indicator charts and graphs used throughout this site.