July 3, 2013
/PRNewswire/ -- Consumers Energy is helping
fish stay cooler this summer even as the days get hotter.
Last August, the utility installed an upwelling system in the reservoir behind Tippy Dam to benefit downstream fish species that thrive in cold water, such as brown trout and Chinook salmon. This allows dam operators to essentially lift water from the deeper, colder, portion of Tippy pond into the plant's intake area to provide cooler flows downstream.
Operators will activate the system during especially warm spells in the summer. In order to maintain a cold water supply, the "bubbler" will run only at night for six hours when needed. During initial testing in 2012, the system lowered downstream water temperatures two degrees. Design tests indicate it may be able to reduce the water temperature up to three degrees.
"Study after study has shown that trout and young salmon become stressed when river temperatures get much higher than 70 degrees," said
, fisheries biologist with the Michigan Department of Natural Resources. "It may not sound like much, but a couple-degree reduction in water temperature can make a huge difference in keeping the temperature below that threshold and in making a river habitat hospitable to cold-water fish species."
Tonello points out that the upwelling system is the next step in river habitat improvements. Fish populations and anglers have been benefiting from Tippy Dam being operated by federal license agreement as run-of-river since 1994.
"The more steady flows that have resulted from run-of-river operations have provided a tremendous benefit and has allowed us to create an excellent year-round brown trout fishery below Tippy, and it has certainly improved Chinook salmon natural reproduction," said Tonello. "Efforts to keep the downstream flows cooler should improve the health of the fish even more, and in turn, make anglers happy."