Where does the water go? That’s the question that has puzzled scientists and random hikers along the Brule River for decades.

Upstream from the Devil’s Kettle waterfall at Judge C.R. Magney State Park, the river splits in two at a rock outcropping. “The east side of the river plummets 50 feet into a pool, in typical waterfall fashion,” according to Minnesota Department of Natural Resources “Field Notes” in the March/April 2017 issue of Minnesota Conservation Volunteer magazine. “But on the west side, the water plunges into a cavernous hole in the rock and vanishes.”

Where does it go?

In late fall 2016, hydrologists Heather Emerson and Jon Libbey measured water flow above Devil’s Kettle at 123 cubic feet per second. Several hundred feet below the waterfall, the water was flowing at 121 cubic feet per second. “In the world of stream gauging, those two numbers are essentially the same and are within the tolerances of the equipment,” Green explains. “The readings show no loss of water below the kettle, so it confirms the water is resurging in the stream below it.”