Lake Superior’s high water level threatens shoreline

Published 8:24 am Thursday, October 12, 2017

DULUTH — Lake Superior’s water level is near a record high after an unusually wet summer and early fall in Minnesota, leading to concerns about damage to its shoreline.

The Star Tribune reports that the lake was about 603 feet (184 meters) above sea level in September, the highest point it’s reached since 1997. It is 2 inches short of the record set in October 1985.

The high water level has damaged docks and caused water to seep into nearby homes.

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The raised water under Duluth’s sandy soil has led to lake water seeping into aging sanitary sewer pipes, said Eric Shaffer, chief engineer of utilities for the city.

“Rainwater doesn’t have anywhere to go,” he said. “Everything’s saturated.”

Residents in Duluth’s Park Point Community Club are concerned that stormy months ahead will raise water levels even more, said Dawn Buck, the club’s president.

The lake basin has been getting above average rainfall for the past 10 years, said Missy Kropfreiter, a hydraulic engineer with the U.S. Army Corps of Engineers’ Detroit District. The basin received 30 percent more rainfall than average last month, she said.

Some property owners are asking officials to let out some of the lake’s water, but international regulations dictate outflow procedures.

“This is not just a U.S. facility or a U.S. lake, there is an international interest at stake here. … There’s an official process that has to occur,” Kropfreiter said. “We can’t just rip open a bunch of gates to draw the lake down.”

Six of the lake’s 16 gates are open and releasing water, compared with the five gates that were open this time last year, Kropfreiter said. Releasing too much water too quickly could create problems downstream, she said.

“It’s always like a balancing act,” Kropfreiter said.