(Portland, OR) -- The Columbia Riverkeeper is suing the U.S. Army Corps of Engineers over the effects of four dams on the Columbia River between the Tri-Cities and Portland, Oregon. The lawsuit alleges the dams cause the water temperature to rise, which kills sockeye salmon. The dams also release illegal pollution. The lawsuit seeks to force the Corps to run more water through the dams to reduce the river temperature and to eliminate releases of pollution.