Patches of cold river water, called refuges or CWRs, are vital to spawning salmon populations in river systems such as the Columbia in the Pacific Northwest. For this reason the Oregon Department of Environmental Quality (DEQ) includes these natural resources in the agency’s legal framework for water quality standards. Oregon DEQ strives to ensure that CWRs are “sufficiently distributed so as to allow salmon and steelhead migration without significant adverse effects.”
Oregon DEQ is participating in a U.S. EPA and National Oceanic & Atmospheric Administration effort to research whether the CWRs in the Columbia River are sufficient to protect migrating salmon species. Researchers are using the EPA tool HexSim to create a detailed model of the river and track simulated fish populations calibrated based on telemetry data of real fish locations. Researchers are planning to apply the model to different potential land use and hydropower management options and climate change-related river warming scenarios.
Learn more here.