This is an excerpt from the June 15, 2020, episode of What's Up With Water. This episode reports on how efforts to protect salmon in the Pacific Northwest could affect the region’s dams. Last month, the U.S. Environmental Protection Agency issued a long-awaited proposal under the Clean Water Act, which would limit water temperatures in one of the country’s largest river systems. The limits apply to some 900 miles of the Columbia and Lower Snake rivers in Oregon and Washington. The intent is to protect endangered salmon and other aquatic species from overheating in waters affected by thermal stress.