Lake Co. Dam Reopens, Handles Recent Floodwaters

LAKE COUNTY, IL — The Grandwood Park community, the Grandwood Park Park District and the Lake County Stormwater Management Commission celebrated the grand reopening of the Grandwood Park Lake Dam at a ribbon cutting ceremony on Friday, Sept. 20.

"In 2012, we started having a lot of problems with the dam. We had one flooding event after another, more damage, and increasing issues," said Nancy Carlson, GPPD President.

The dam was also in danger of collapse, according to a news release from the Stormwater Management Commission. Through the Mill Creek Watershed Plan, it was declared a significant safety hazard and steps were immediately taken to rehabilitate it.

Construction officially began in November 2018. The dam passed its first test last week after successfully doing its job to handle the recent rains and resulting floodwaters.

“When the project first began, the dam was ready to give way,” said District 7 Lake County Board Member Steve Carlson. “I would like to commend all of our partners who took immediate action to ensure this rehabilitation would take place. We are happy to say that this dam will help prevent flood damage in this community and will maintain the precious wildlife that live this area.”

The dam was designed to increase control over high water events, which will help minimize shoreline erosion caused by fluctuating water lines and as a flood hazard reduction from greater control of outflow.

"The Grandwood Park Dam rehabilitation project aligns with LCSMC's mission to improve water quality, reduce flood damages, and restore and enhance the natural drainage system," said Mike Warner, LCSMC Executive Director, who oversaw the project. "We were proud to be a part of it."

In the Mill Creek watershed plan, Lake County's stormwater management commission identified the need for replacement of the old dam based on analysis of the dam structure and embankment, impact of the dam to surrounding residents and the region.

That recommendation resulted in the project scoping process and provided the basis for the funding and staff request to complete the project. LCSMC, and a Lake County infrastructure fund award, provided 40 percent ($170,000) of the project cost for the dam renovation, according to a news release.

The construction on the project officially began in November 2018. The new dam configuration includes a concrete-enhanced primary spillway and 80-ft stone armored secondary spillway —which directs overflow to a controlled area—and a new, high-quality wetland area.