Umatilla River Subbasin Plan

The Umatilla/Willow subbasin is located near the center of the Columbia basin and accounts for approximately 1.7% of the total area of the Columbia basin in the United States. The Umatilla River flows into the Columbia River at RM 289 and Willow Creek enters at RM 253. Three major Columbia River dams (the John Day, The Dalles, and Bonneville dams) are downstream of these confluences.

The Umatilla/Willow subbasin is one of ten subbasins grouped in the Columbian Plateau ecological province, which is the largest of the 11 ecological provinces. Because subbasins in the Columbia Plateau province are grouped together based on similarities in climate and geology, the Umatilla/Willow subbasin and most other subbasins in the province were historically dominated by interior grasslands and/or shrub-steppe habitats, are currently dominated by agricultural lands, have low human population densities, and have large portions of land in private ownership. The importance of agriculture and the arid nature of the area also results in a problem common in most other subbasins in the province: water is over-appropriated and is required for multiple, sometimes competing purposes. Like most other subbasins in the province wildland recreation, including fishing, hunting, boating, and hiking, is also an important component of the economy and culture of the Umatilla/Willow subbasin.

The fish and wildlife of the Umatilla/Willow subbasin are also related to other subbasins in the province. For example, bull trout of the Walla Walla, John Day, and Umatilla/Willow subbasins belong to the same gene conservation group. In addition, the Umatilla/Willow, John Day, Yakima, and Walla Walla subbasins share the same Middle Columbia River Steelhead evolutionarily significant unit (ESU). Many of the terrestrial wildlife species found in the Umatilla/Willow subbasin are also found in other subbasins in the province, with mobile species often moving between subbasins in the province. Fish and wildlife in the Umatilla/Willow subbasin face many of the same problems that threaten species in other subbasins of the province, both from within and outside of the subbasin.

Although the Umatilla/Willow subbasin is similar in many ways with the other subbasins in the province, it is unique in other ways. Perhaps most notable is the way in which stakeholders in the Umatilla/Willow subbasin with different interests have worked together to improve fish habitat in the Umatilla River through the Umatilla Basin Project, as describe above. The subbasin is also unique in other ways related to water resources and the presence of salmonid species. Extirpated Chinook and coho salmon have been reintroduced to the subbasin, and their production, as well as steelhead production, has been increased through hatchery supplementation. Natural production of steelhead is increasing as well; returns of Middle Columbia River ESU natural summer steelhead adults are increasing more rapidly in the Umatilla River than in the Walla Walla or John Day subbasins. The Umatilla/Willow subbasin also provides important habitat for many salmonids. Although the subbasin contains only about 1.5% of all the river miles in the U.S. portion of the Columbia basin and 6% of all the river miles in the Columbia Plateau province, it provides a disproportionate amount of salmonid habitat.

The terrestrial environment in the Umatilla/Willow subbasin is also unique in that it contains some of the largest remaining tracts of shrub-steppe habitat in the Columbia Plateau in Oregon.

Environmental conditions external to the Umatilla/Willow subbasin impact both fish and wildlife species in the subbasin. Anadromous fish leaving the subbasin as juveniles and returning as adults are affected by multiple aspects of the aquatic environments they encounter in that journey, including three major dams on the Columbia River, and variable estuary and ocean conditions. Passage barriers, poor water quality, flow issues, and predation are some of the obstacles facing these fish outside the subbasin. In addition, salmon and steelhead abundances are influenced strongly by ocean conditions including the PDO. Likewise, highly mobile terrestrial wildlife species are also affected by out-of-subbasin conditions. These may range from problems such as loss of habitat connectivity in adjacent subbasins to deforestation of wintering habitat in South America.

Summary of the Management Plan

The management plan for the Umatilla/Willow subbasin begins with a vision statement, which describes the desired future condition of the subbasin and reflects the current conditions, values, and priorities of the subbasin in a manner that is consistent with the Council’s vision described for the Columbia basin. The following vision statement for the Umatilla/Willow subbasin was adopted by the Core Partnership on November 6, 2003 and was presented and approved at a public meeting on November 12, 2003.

The vision for the Umatilla/Willow subbasin is a healthy ecosystem with abundant, productive, viable, and diverse populations of aquatic and terrestrial species, which will support sustainable resource-based activities that contribute to the social, cultural, and economic well-being of the communities within the subbasin and the Pacific Northwest.

This vision entails several broad goals for the subbasin that can be categorized as human use; habitat; population; and research, monitoring, and evaluation goals.

Human Use

  • Provide for non-consumptive recreational, educational, aesthetic, scientific, economic, cultural, and religious uses of the subbasin’s diverse fish and wildlife resources
  • Provide for sustainable consumptive, ceremonial, subsistence, and recreational uses of the subbasin’s diverse fish and wildlife resources.
  • Provide for sustainable resource-based activities to support the economies and cultures of the communities within the subbasin.


  • Protect existing high quality fish and wildlife habitat and strongholds.
  • Restore and enhance degraded and diminished fish and wildlife habitats to support population restoration goals and to mitigate impacts from the construction and operation of the Columbia basin hydropower system and other anthropogenic impacts.
  • Restore the health and function of ecosystems in the Umatilla/Willow subbasin to ensure continued viability of their natural resources.


  • Maintain and enhance the diversity, abundance and productivity of existing fish and wildlife populations within the subbasin.
  • Strive for de-listing and avoidance of future listings of native fish and wildlife species in the subbasin under state and federal Endangered Species Acts.
  • Restore and maintain self-sustaining populations of extirpated species consistent with habitat availability, public acceptance, and other uses of the lands and waters of the state.

Research, Monitoring, and Evaluation

  • Develop a research, monitoring, and evaluation plan for the ecosystems of the subbasin that is consistent with and complements the larger regional efforts to track the status of fish and wildlife populations and their habitats as needed for appraising management actions, the results of these actions, and for evaluating other environmental changes.

The development of objectives and strategies for the subbasin’s aquatic and terrestrial wildlife management plan was driven by the vision, the current biological and ecological conditions in the subbasin, and the economic and social realities described in the assessment. The biological objectives describe the physical and biological changes within the subbasin needed to achieve the vision. When forming aquatic and wildlife biological objectives and strategies, subbasin planners worked to satisfy the criteria set forth by the Council (2001) in its Technical Guide to Subbasin Planners and to ensure consistency of the plan with the requirements of the Endangered Species Act and the Clean Water Act.

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