If you happen to have time later today Monday, and would like to pop down to Milwaukee’s port, you can participate in a unique tour.
Organizations concerned about contaminants that have long muddied Milwaukee's rivers and harbor will share plans for the sediment's removal. It's part of a massive initiative to clean up what the EPA calls an "area of concern." The sediment won't be traveling far as it will be secure in a new, sealed storage facility off the shore of Lake Michigan.
It’s old news that the region’s industrial past left behind a rich history, some mighty fine beer and other products. It also left heaps of pollution that made its way into Milwaukee waters and sediment and, for the most part, stayed there.
Bridget Henk of the Milwaukee Metropolitan Sewerage District says the contaminated sediment is slated to be removed.
“The EPA is going to be doing the dredging of the Milwaukee estuary area,” Henk says.
I met Henk on a recently windy morning in the shadow of the Hoan Bridge, with salt piles and Jones Island to our backs. The Lake Express ferry terminal is just to our south. The civil engineer gazes east to Lake Michigan, where she says part of the remedy lies.
Henk is managing what’s call the dredged material management facility or DMMF.
It will be a 42-acre watertight storage space that will be built just off the shore, with lakebed as its base.
“The lakebed is a very thick clay layer and that is not porous, so it doesn’t allow for water to go through. So we can keep the existing lakebed as the base of our material. I anticipate your next question. What are the sides? So we are doing something called a dual sheet pile wall with bulk barrier design,” Henk says.
Henk says workers will pound two rows of sheet pile into the lakebed.
“So what that means is there’s two parallel rows of sheet pile with that concrete structure between to prevent water [from passing] through – so it is a watertight system and that will be along all four sides,” Henk says.
As the sediment is dredged from the estuary, the wet materials will be pumped to the lakefront, where water will be removed, treated, and returned to the lake. The sediment is stored in the facility.
”That process is pretty complicated, there’s a lot of steps involved in it, but one of the biggest steps is water treatment, and cleaning out the water as it goes through the process,” Henk says.
That task will be the job of a water treatment facility that will be constructed adjacent to the DMMF. Henk says It will take up to two construction seasons to build the storage structure.
How long before the DMMF is filled up and capped off?
“The EPA portion, it will seem pretty full when they’re complete approximately five to seven years from now,” Henk says.
The area of concern dredge material will bring the DMMF up to about 75% capacity. It will take time for the stuff to firm up because it’s going to be very soft. So, it will take about 10 years or more for that material to settle,” Henk says.
The remaining space will gradually be filled by smaller sporadic estuary projects. “The sewerage district [MMSD] and Port Milwaukee will be placing our materials into the facility. It’s going to take us a long time to fill up the remaining capacity. So, we’re looking about 40 to 50 years from now when this land will be usable,” Henk says.
Gazing out at what is now water, Henk sees into the future – the facility full, and the public will have 42 acres of land overlooking Lake Michigan to enjoy. “[It is] something that could be used by future generations; there aren’t many opportunities for that,” Henk says.
Henk says it’s critical to engage residents in thinking about the use of that land. She hopes lively conversation to begin now throughout the community.
“At our walking meeting Monday, the community advisory committee is going to be gathering feedback on what people think could be here,” Henk says.
But Henk says it’s important not to lose sight of the significance of removing heaps of contaminated sediment out of the estuary. “We’re taking it out of a space that is being used daily, recreationally and moving [it] to a place where it’s safely contained. So you don’t have that daily interaction with it anymore,” Henk says.
The MMSD and other local groups, state and federal agencies call the cleanup a generational opportunity to improve the environment.
A walking tour, offering information about the project will take place Monday, June 13. Groups will leave every 10 minutes from The Port Milwaukee Administration Building between 5:30 pm and 7:00 pm. A virtual tour will also be available.
Editor's note: The audio incorrectly states the tour ending time as 7:30 pm.
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