Plans Afoot to Restore Small Wetland Within Milwaukee’s Evolving Harbor District

Dec 4, 2017

Before the City of Milwaukee was the Milwaukee we know, it was a massive marsh and wetland system fed by the Milwaukee, Menomonee and Kinnickinnic Rivers. By the 1850s, the wetlands were filled in and replaced by factories and foundries. By some miracle, one small bit of wetland – now called the Grand Trunk - survived along the harbor’s south central edge.

Despite the channelized Kinnickinnic River just to the wetland's west, endangered garter snakes and other native critters are still found in the 6.5 degraded acres.

The wetland's renaissance is included within Milwaukee’s harbor district plan, called the Water and Land Use Plan.

The plan calls for restoring the Grand Trunk’s forest and grassland habitats. Its ephemeral ponds will again bubble with life and Northern Pike will spawn in its waters.

And for us humans, planner envision a kayak and canoe launch and boardwalks to observe life within the wetland.

It’s safe to say, lots of work and clean up must happen first.

But, according to Benji Timm, teams will soon transition from planning to clean up. As manager of the wetland project, Timm is juggling the rules and regulations of multiple agencies and input from specialists.

Credit Susan Bence / Milwaukee Public Radio

We met as archeologists were determining whether the parcel contains any meaningful artifacts. All they came up with was the remnants of a wooden boat and a few railroad ties.

Timm says that information puts the city a step closer to restoration. “We have to comply with the NEPA, the National Environmental Policy Act.  The wetland delineation is also part of that and we’re trying to beat the weather right now too."

Delineation means figuring out where the wetland starts and ends.

One vision of how people might enjoy the restored Grand Trunk Wetland. This image is included in the draft water and land use plan.
Credit City of Milwaukee

Ecologist Mark O’Leary took on that task earlier this autumn. First he had to fight his way through a thick sea of invasives. But O’Leary says some native plants are holding on.

He looked for plants that grow and soils that form under wetland conditions. “We have to find out if water is within about 12 inches of the surface during two weeks during the growing season. You find that out by what the plants are and then you poke holes in the ground to figure out what the soils look like and then you draw a line around the boundary of it,” O’Leary says.

But the Grand Trunk site made those steps difficult. “It’s a challenging site because it’s mostly fill. The soil is a big part of finding out where the wetland boundary is and it’s kind of hard to find out where it is when there’s so much fill on it,”he says.

The wetland is part of a larger 27 acre parcel. Over the years crews dumped road construction material on the site and in some places, fill was piled more than 10 feet high.

“You poke holes, you document what your find, make a judgment call and have a conversation with the DNR,” O'Leary explains..

Some soils here are contaminated. O’Leary says other experts will deal with that challenge. “That becomes some of the base information for developing the plan. But then, some of the biggest drivers are going to be...how are we going to restore the hydrology...you have precipitation, which all wetlands have to deal with and then you have fluctuating lake levels that happen seasonally and regularly over several years."

O’Leary says a team will formulate methods to build up native wetland plants to target wildlife. "It’s ecologists working with landscape architects, working with engineers and working with the stakeholders,” he says. Lindsay Frost works with Harbor District, Inc., which held outreach events and carried out surveys to learn what’s most important to neighbors.

Credit Lindsay Frost

Frost learned people care deeply about the future of the Grand Trunk wetland.

“Over and over we kept hearing 'controlled public access' so a way to experience the site while still allowing the ecology to take place and helping to preserve that too,” she explains.

Ecologist Mark O’Leary calls it a trophy site.

“There’s nothing left of the historic estuary left. So we have this one place to show what it was, to educate people and try to bring the wildlife back to it.” O’Leary adds, “It’s our last shot.”

People interested can also take a closer look at the plan and share their thoughts. An open house is scheduled today, Monday, from 4 to 6 pm at the new Mitchell Street Library.