HOME > PLANNING > ECOREGIONAL ASSESSMENTS> COLUMBIA PLATEAU

Covering 74 million acres, the Columbia Plateau stretches across the sagebrush steppe of southern Idaho, connecting the Columbia Basin of eastern Washington and Oregon to the northern Great Basin of Nevada, Utah and California. Essentially the Plateau is a broad expanse of sagebrush covered volcanic valleys, punctuated by isolated mountain ranges and the dramatic river systems of the Snake, Owyhee, Boise, and Columbia Rivers.
Despite the relative dearth of precipitation throughout the region, however, the Columbia Plateau is home to an abundance of plants, animals and unique habitats. Approximately 72 endemic plant species are found in the ecoregion.

Nearly half of the Columbia Plateau ecoregion is owned by the U.S. federal government, much of which is managed by the Bureau of Land Management. Valley bottomlands, stream drainages and arable lands are all largely in private ownership. Land conversion, mostly to foster intensive agriculture, has occurred to a considerable extent on private lands. Additional information on this ecoregion is available from the Washington Biodiversity Council.

Assessment Summary:

• Published in 1999
• Portfolio of 139 priority conservation areas
• Conservation portfolio covers 20% of the ecoregion
• 451 conservation targets identified

All the data, decision support tools, and site priorities from the assessment are available to inform and support partner conservation and management efforts. Please use these links to download specific components of the ecoregional assessment.

The spatial data available here represents the most basic level of information produced in the assessment. To access more in-depth data and
information, please .