NW drinking water concerns could get worse as the climate changes

Thunderstorms high in the Cascades recently stirred up a lot of dirt in a central Washington river, causing problems for people on its banks.

All the dirt in the Naches River was too much for the City of Yakima’s water treatment plant to handle. Desert cities and towns could see situations like this happen more often as the climate continues to change.

Climate change will cause more storm runoff, change when snowpack melts and lead to more severe wildfires and harmful algal blooms, said Amanda Hohner. She studies how post-wildfire runoff affects drinking water treatment plants.

“At least in the Western U.S., the effects of wildfire and also climate change are really starting to challenge drinking water treatment plants, resulting in different water quality than maybe those water treatment plants were designed for,” Hohner said.

In the Northwest, climate change is expected to alter how precipitation falls. Changes in snowpack and streamflow could mean places like the Yakima Basin in Washington and the Willamette River Basin in Oregon have bigger chances for more frequent water shortages in the summer, according to the University of Washington Climate Impacts Group and the Oregon Climate Assessments.