Lake County study: Foxconn development to increase Des Plaines River flooding

The large Foxconn development in southeastern Wisconsin will increase flooding along the Des Plaines River and degrade the quality of the waterway, a study commissioned by the Lake County Stormwater Management Commission concluded.

According to the study, some damage already has been done. Phase one of Foxconn construction has filled in 38.81 acres of wetlands. During heavy rains, wetlands absorb water and release it slowly, which helps mitigate flooding.

The construction also has led to soil erosion, which has sent sediment downstream through the Des Plaines River, according to the Lake County study. Experts say that will damage the quality of the river downstream in Illinois.

Foxconn plans to build a flat-screen manufacturing campus in Mount Pleasant, about 70 miles north of Chicago. Local officials and Republican state lawmakers - led by then-Gov. Scott Walker - extended the company an unprecedented $4 billion in incentives and exempted the Taiwanese electronics giant from a host of environmental regulations, allowing the company to fill wetlands without a permit and to proceed without an environmental-impact statement.

The Lake County study, which was presented Thursday night, urges Wisconsin officials to require Foxconn to compensate for the lost wetlands and to prevent soil loss at construction sites. It also calls for Wisconsin to make its stormwater detention standards consistent with Lake County's standards.

"They're following Wisconsin's rules, but their rules aren't as strict as Lake County's," Gurnee Mayor Kristina Kovarik said. "We require more and better runoff management practices, which allows water to be released slowly and not inundate the property next to you."

In a column written for the Daily Herald and published over the summer, Republican Robin J. Vos, speaker of the Wisconsin State Assembly, addressed environmental concerns raised by Illinois officials and said "any worries about flooding downstream should be put at ease."

"The nonpartisan Southeastern Wisconsin Regional Planning Commission has determined the proposed stormwater management system would actually help maintain or decrease runoff in the Des Plaines River watershed," he wrote.

Lake County commissioned its study from Rosemont-based Christopher B. Burke Engineering Ltd. in July. The full report is available on lakecountyil.gov/553/Stormwater-Management-Commission. The public comment period is open until April 8.

Kovarik, who sits on the county stormwater commission, said it is clear that a lot more water is going to come downstream faster as a result of Foxconn.

"It doesn't look good for future flood events or heavy rains," Kovarik said.

Lake County has spent around $30 million and Gurnee has spent $5 million to $6 million buying properties near the river to mitigate the effects of flooding, work that could be undone if Foxconn doesn't take precautions, Kovarik said.

• The Associated Press contributed to this report.