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WUWM's Susan Bence reports on Wisconsin environmental issues.

Contaminated sediment removal from Milwaukee River impacts summer activity but leads to cleaner estuary

Recreation and commerce will have to share sections of the lower Milwaukee River with dredging this summer.
Susan Bence
/
WUWM
Recreation and commerce will have to share sections of the lower Milwaukee River with floating dredging equipment this summer.

Milwaukee’s rivers that converge downtown and feed into Lake Michigan, were once dumping grounds for industrial pollution.

In recent years, they’ve become assets, with condos popping up along the shore and boats filling the waterways. But this spring and summer, recreation and commerce will have to share sections of the lower Milwaukee River with dredging equipment.

Advocates say it's an important step in lifting the Milwaukee Estuary off the EPA’s Great Lakes Areas of Concern list. A huge crane “planted” in the lower Milwaukee River off Erie Street blocks our view of the inner harbor to our east.

“They’re putting in a redundant steel wall here,” says Cheryl Nenn with Milwaukee Riverkeeper.

An extended conversation with Cheryl Nenn.

It’s among the local partnerscelebrating the removal of loads and loads of contaminated sediment from 6/10 of a mile of river over the next few months.

“It’s about 45,000 cubic yards of contaminated sediment, which will be removed in this section of the river,” Nenn says.

Imagine stockpiling stuff 21 feet high within a football field. According to We Energies that’s what 45,000 cubic yards amounts too.

Although the pipeline carrying contaminated sediment is anchored to the river bottom, signs and floating barriers warn boats large and small to keep out of the dredge area.
Susan Bence
/
WUWM
Although the pipeline carrying contaminated sediment is anchored to the river bottom, signs and floating barriers warn boats large and small to keep out of the dredge area.

Nenn says the utility is leading this phase of the estuary deep clean. "They are basically funding a very healthy amount of the 35% match that we need to put up to get the 65% of the money that's coming from the (federal) government to pay for this project," she says.

That’s because several We Energies corporate predecessor’ that operated pre Clean Water Act left pollution in their wake, including, “The Third Ward Manufactured Gas Facility," says Nenn. "It was operational from 1852 to 1960. That is why there is a lot of contamination in this section of the river.”

The pollution led to the Milwaukee estuary being listed an EPA Great Lakes Area of Concern, which means the legacy contamination remains a threat to aquatic life and humans.

Crews are out six days a week, working 10 to 12 hour shifts to remove the pollution that’s been left behind. We watch a worker on a small movable barge mechanically lower an arm into the water. Nenn says it basically works like a super powerful vacuum cleaner.

The contaminated sediment is currently being piped 1.5 miles to this dredged material facility owned by the U.S. Army Corps of Engineers. An additional facility will be constructed just north (right of the line of boulders) to hold additional sediment removed from the Milwaukee estuary as the project continues.
We Energies
The contaminated sediment is currently being piped 1.5 miles to this dredged material facility owned by the U.S. Army Corps of Engineers. An additional facility will be constructed just north (right of the line of boulders) to hold additional sediment removed from the Milwaukee estuary as the project continues.

“The material that’s being taken out here is basically being pumped in underground pipeline or pipes,” Nenn says. Then it travels to a sediment facility in the Milwaukee harbor about a mile and a half from where we’re standing.

The sediment has been “resting” at the bottom of the river undisturbed for decades, so Nenn says the jostling of the hydraulic dredging will result in some pollutants escaping to the surface.

This small boat equipped with an absorbent boom sweeps the site to absorb materials that might rise to the surface during the dredging process.
Susan Bence
/
WUWM
This small boat equipped with an absorbent boom sweeps the site to absorb materials that might rise to the surface during the dredging process.

“So they’ve been putting some absorbent booms out and pads to soak up as much of that as possible,” Nenn says.

We watch as a small boat pulling some sort of absorbent material motoring back and forth next to the dredging barge.

“It actually looks really good today, but when it first started we were getting calls from the condos about oil, like oil sheen,” Nenn says.

We spot one of several small data stations bobbing in the river. Nenn says they’re collecting water quality impacts up and downstream from the dredging. “We have gotten quite a few calls from folk about that,” Nenn says.

And a Wisconsin DNR-approved plan is tracking air quality, noise levels and vibrations throughout the project.

The project plan evolved before dredging began. Neighbors worried about damage to their condos foundation, so this crane is 'helping' to install a temporary additional sea wall along the building.
Susan Bence
/
WUWM
The project plan evolved before dredging began. Neighbors worried about damage to their condos foundation, so this crane is 'helping' to install a temporary additional sea wall along the building.

But residents of condos furthest downstream in the project zone still had concerns — the dredging might damage their building's foundation.

That brings us back to the crane reaching up high in the sky. It’ here to help install a second layer of protection. “They started putting in the steel wall here. And then they’ll dredge waterward of that wall, and then when they’re done with the dredging, they will come in with divers and cut that wall off,” Nenn says.

Crews will then cap the river bottom closest to the building. “With some clean fill material because they not going to be able to remove some of the contamination that’s very close to the sea wall,” Nenn explains

Nenn says summer will look very different along the Third Ward section of the Milwaukee River. Walkers will occasionally be restricted from strolling the riverwalk. Some public and private docks will be closed. Boats and kayakers will have to share a narrow stretch of water.

“Almost half of the river will be shut down to boat traffic. The south part will be open in this kind of east west portion for the summer,” Nenn says.

Nenn and other advocates have the long view in mind. We spot a duck with his or her wee ducklings scurrying excited in the river below.

A family surveying the dredging project along the Milwaukee River.
Susan Bence
/
WUWM
A family surveying the dredging project along the Milwaukee River.

“We’re excited that it’s finally starting. Many of us have been in meetings for 20 years — studying where the contamination was, the level of contamination in the fish, the level of tumors in the fish, the amount of contamination in birds that eat aquatic insects,” she says.

Nenn looks forward to a day when wildlife and humans can rely on a swimmable, fishable estuary.

Questions about this phase of the estuary cleanup? Call We Energies at 877-380-0522 or email thirdwardproject@we-energies.com.

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Susan is WUWM's environmental reporter.
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