When settlers constructed damns in the upper Yakima Basin without fish passage in the early part of the 20th century, lake and river ecosystems were profoundly impacted. One species that was particularly affected was bull trout. These dams isolated headwater populations of bull trout from one another on a local and regional scale. Furthermore, the dams stopped salmon, an important food source for bull trout, from returning to these systems. Many of these bull trout populations, including the upper Kachess River population, are in decline. To this end, this project aims to identify key actions we can take to protect this population before they disappear.
The upper Kachess River Restoration is located at the top of Little Kachess Lake. The project’s primary focus area is the eastern floodplain and associated tributaries. Looking at historical maps, we can see human activities like roads, mining, and forest management altered the landscape and disrupted the floodplain. Therefore this assessment encompasses the entire watershed so we have a complete picture of the impacts of human disturbances.
The assessment study area begins at the confluence of the Kachess River with Little Kachess Lake and extends upstream approximately 2.5 miles to a barrier falls. The upper Kachess River drains a 28.5 square km high mountain watershed in the Cascade Mountains of northern Kittitas County. This watershed contributes cold, clean, high-quality water to the upper Yakima River system.
Currently, Kittitas Conservation Trust is conducting a comprehensive hydro-geomorphic and watershed evaluation. The evaluation will identify the causes of bull trout mortality in the upper Kachess River, including seasonal dewatering, spatial constraints and habitat degradation. The information gained will allow us to identify and prioritize restoration actions to improve spawning, rearing, and migratory conditions.
For more information on the project, you can visit the Washington State Recreation and Conservation Office’s Project Snapshot: https://secure.rco.wa.gov/prism/search/ProjectSnapshot.aspx?ProjectNumber=16-1742