Columbia River Basin

The Biodiversity Atlas project focuses on the Canadian portion of the Columbia River Basin within the geographic scope of its primary funder - the Fish and Wildlife Compensation Program (FWCP).

A Pilot Project in the grasslands, wetlands and forests of the East Kootenay region of Canada's portion of the Columbia River Basin was developed in order to test the concept of a Biodiversity Atlas.

This page provides background information about the Columbia River Basin in order to introduce you to the biodiversity in this area.

Communities and stakeholders on both sides of the border rely on the health and biodiversity of the Columbia River Basin.

Learn more about the Columbia River

• The Columbia River Basin
• Map of Columbia River Basin in Canada
• Map of entire Columbia River Basin in Canada and the United States

Columbia River Basin Facts

The Columbia River Basin is the fourth largest watershed in North America.

The Columbia River drains a 67 million-ha Basin that includes territory in seven states (Oregon, Washington, Idaho, Montana, Nevada, Wyoming, and Utah) and British Columbia.

British Columbia accounts for only 10 million ha of the watershed, the headwaters and 800 km of the 1,920-km Columbia River are located in British Columbia.

The Canadian portion of the Columbia River is about 10 million ha and includes the Similkameen and Okanagan Valleys, most of the Kootenay River, part of the Flathead River, and the headwaters of the Columbia River itself. It is dominated by a series of mountain ranges: the Rocky Mountains to the east, the Purcell and Selkirk Mountains, and the Monashee Mountains to the west.

Although humans have lived along the Columbia River for more than 10,000 years, modern engineering in the 19th and 20th centuries has dramatically altered the Columbia River.

The Columbia River Basin in Canada is a very biologically diverse ecosystem.

• 67% of vertebrate species in British Columbia and 48% of total vertebrate species in Canada live in the region.
  
• Most of the animal species and many of the broad ecosystems found throughout the Canada-U.S. Columbia Basin are found in the British Columbia portion of the Basin - several are only found only in British Columbia.
  
• Species diversity is high for all known groups of organisms.
  

The Columbia Basin does not correspond to a coherent geologic region, but is crossed by a fundamental geologic boundary that separates Laurentia, ancient North America, from exotic terrain that collided with Laurentia during the Mesozoic period.

This geologic collision ultimately formed a unique and widely diverse land mass characterized by:

• cool, moist, mountainous, forested ecoregions;
  
• extensive plateaus, plains and basins as well as Mediterranean-type, semi-arid, subarctic and alpine climates;
  
• forests dominate the vegetation; and areas of grasslands, wetlands, scrub and tundra are extensive.
  

The middle and lower reaches of the Columbia River in British Columbia and the United States portion have been extensively modified by human activity including the construction of an estimated 400 dams.

The valley bottoms have also been heavily modified by industrial development, rural settlement, farms, transportation routes, communication systems and communities.

Drainage systems are complex and many community watersheds are connected to the Columbia system.

The Columbia River is the dominant river system in southeastern British Columbia and the Pacific Northwest United States encompassing Idaho, Montana, Oregon and Washington.