by Emily Howe, aquatic ecologist
Communities of the Yakima Basin are intimately bound to the river. Flowing like life-giving arteries through the arid landscape, the Yakima River and tributaries provide the majority of water for this vital valley known for its rich agricultural legacy, world-class orchards, and once prolific salmon runs.
Save for its forested headwaters, the landscape is largely scrubland – devoid of rain most of the year. Yet the river provides snaking coils of green floodplains and irrigated crop circles all the way through sagebrush country to the Columbia River confluence. The rivers that sustain the Yakima Valley don’t get their water from the sky in spring. They swell due to melting snowpack from the Cascade Mountains above. And for the most part, water storage in the Yakima Basin isn’t found in the reservoir system, it’s in the snowpack itself.
But that snowpack is dwindling. As a result, water security in Yakima and across the American West is increasingly melting away. Data from the SNOTEL network, 700 stations in 13 Western states, reveal a 41% decrease in annual snow mass since 1982, with a snow season shortened by 34 days.
River valleys are thirsting for water—and the climate is warming. This climate-induced water stress compounds with a legacy of fire suppression in upper watershed forests, exacerbating drought symptoms not only in the rivers below, but also for the forests themselves as overstocked trees compete for water. And likewise, water insecurity stresses communities. Water users not protected by reservoir systems or priority water rights increasingly face a hard, dry reality; water curtailments are expected in 75% of years by the end of the century.
We’re working to identify how tree canopy conditions interact with snowpack in the eastern Cascades so that we can build restoration strategies that both protect snowpack and reduce wildfire risk. This confluence of fire and ice is critical to ecosystem integrity in a changing climate, not only for river ecosystems, but for the people, fish, and wildlife that rely on them.