Columbia River Cold Water Refuges Plan

Project description

The Columbia River Cold Water Refuges Plan focuses on the lower 325 miles of the Columbia River from the Snake River to the ocean (see map). Cold water refuges serve an increasingly important role to some salmon and steelhead species as the Lower Columbia River has warmed over the past 50 years and will likely continue to warm in the future due to climate change. The Columbia River Cold Water Refuges Plan is a scientific document with recommendations to protect and restore cold water refuges. By issuing this plan, EPA is meeting its responsibilities under the Endangered Species Act associated with its approval of Oregon’s temperature standards for the Columbia River. This plan also serves as a reference for EPA’s Columbia and Snake Rivers Temperature Total Maximum Daily Load (TMDL). The plan: Describes available cold water refuges (CWR) in the Lower Columbia River. Characterizes how salmon and steelhead use CWR. Assesses the amount of CWR needed to attain Oregon’s Clean Water Act CWR narrative water quality standard. Identifies actions to protect and restore CWR. Recommends future CWR studies. EPA worked with Oregon, Washington, NOAA Fisheries, tribes, and other partners to develop the plan, including receiving valuable input from about twenty contributing parties on an October 2019 draft.

Project results

The plan identifies specific actions to protect and restore CWR (see Chapter 7 for details) that include: Continued implementation of USFS and State forest management plans, and State forestry practice regulations to protect riparian and water quality values Minimizing additional water withdrawals, establish minimum instream flows, and implementing irrigation conservation measures Restoration of riparian and stream habitat to reduce water temperatures in tributaries, improving floodplain connectivity to enhance groundwater connectivity, and restoring flows to help resist warming and increase CWR volumes at tributary confluences. Fisheries closures at CWR locations during critical periods. These have been implemented by the States of Oregon and Washington

Next steps

In addition to pursuit of action priorities identified above, recommendation for future research include: Research to better understand timing and extent of CWR refuge use, particularly as it may relate to areas that are not well studied (below Bonneville Dam), and to changes that have occurred since the foundational studies conducted in the late 1990s and early 2000s. Research to understand physiological benefits (and tradeoffs) associated with CWR use, and effects from elevated thermal exposures particularly as accumulated by migrating adults over the entire course of their pre-spawning migration. Research to better model and predict CWR volumes as a function of tributary and mainstem flow, temperatures, and confluence morphology including sedimentation. More comprehensive monitoring of flow and temperature is necessary to support this. Research to evaluate density effects and carrying capacity of CWR.

More info

Project website: Publications: Ebersole, J.L., Quinones, R., Clements, S. and Letcher, B., 2020. Climate refugia for cold-water fishes under an expanding human footprint. Frontiers in Ecology and the Environment, 18(5): 271-280. Fuller, M.R., Ebersole, J.L., Detenbeck, N.E., Labiosa, R., Leinenbach, P. and Torgersen, C.E., 2021. Integrating thermal infrared stream temperature imagery and spatial stream network models to understand natural spatial thermal variability in streams. Journal of Thermal Biology: 103028. Snyder, M., Schumaker, N.H., Ebersole, J.L., Dunham, J., Comeleo, R., Keefer, M.L., Leinenbach, P., Brooks, J.R., Cope, B., Wu, J., Palmer, J. and Keenan, D.M., 2019. Individual Based Modelling of Fish Migration in a 2-D River System: Model Description and Case Study. Landscape Ecology, 34: 737. Snyder, M.N., Schumaker, N.H., Dunham, J.B., Keefer, M.L., Leinenbach, P., Brookes, A., Palmer, J., Wu, J., Keenan, D. and Ebersole, J.L., 2020. Assessing contributions of cold-water refuges to reproductive migration corridor conditions for adult salmon and steelhead trout in the Columbia River, USA. Journal of Ecohydraulics: 1-13. U.S. Environmental Protection Agency, 2021. Columbia River Cold Water Refuges Plan, EPA-910-R-21-001, Seattle, WA.