Elk Grove Village will investigate whether lowering the level of Busse Lake before heavy rainstorms, or even dredging it, would alleviate flooding along Salt Creek in Cook and DuPage counties.
Salt Creek flooding, "has been a nightmare for Elk Grove and other communities for 50 years and beyond," Elk Grove Mayor Craig Johnson said.
The village got the Cook County Forest Preserve District's blessing to conduct a feasibility study on the recommendations of the Friends of the Forest Preserves.
The environmental group suggested building an adjustable dam replacing the main dam at Busse Woods Reservoir - built in 1976 to contain floodwater primarily from DuPage County - as an alternative to an earlier proposal to expand the reservoir capacity.
By manually lowering the height of Busse Lake, which feeds into Salt Creek, a few days before a heavy rainstorm, "it can hold a lot more and can be released at a slower pace," Johnson said.
"We want to find a way now to make it (the dam) fully operational," Johnson said. "We get the '100-year rain' twice a year now," pointing out that the 2009 Rotary Fest was all but lost due to flooding.
"Hopefully, this is a solution that can work, that the forest preserve and the environmental group supports to help out the communities downstream."
To achieve that, the dam would have to be modified because it is locked and welded at its lowest elevation, said Alan Boffice, Elk Grove director of engineering and community development.
"Because it's as low as it can go right now, it would take some pretty expensive modifications," Boffice said.
DuPage County's engineering department had recommended installing an inflatable rubber dam spanning the eastern half of the existing spillway. That would mean more of Busse Woods would get flooded, said Benjamin Cox, executive director of Friends of the Forest Preserves.
The Busse Woods Reservoir has insufficient capacity to hold excess stormwater from the region, and making the container larger by raising the water level is not the solution, he added.
"If the woods, the trees and the plants are under water for an extended period of time, they will die ... not to mention the other wildlife," Cox said.
He added Busse Woods is home to nine threatened or endangered animal species.
"You can't increase the flooding in that area to such a dramatic extent that it's not natural," Cox said. "And that's what would have happened with (a larger) dam."
A group of Northwestern University engineering students actually came up with the alternate solution that Elk Grove Village will be studying.
Cox said the use of locks to lower water levels ahead of storms has already been proven effective in the Chicago River system and other water bodies in the region. The city will soon begin accepting bids from contractors to perform the study and should have cost estimates within two months, Johnson said.
"Hopefully, by mid-March we'll have a group together to do the study for us," he said. "We now have a way to solve 50 years of flooding in the suburbs."