Forest preserve plans to stabilize river at Mallard Lake
The Forest Preserve District of DuPage County is planning to spend roughly $2.4 million to restore and stabilize a stretch of the West Branch of the DuPage River that flows through Mallard Lake Forest Preserve near Hanover Park.
Mallard North landfill - the oldest of two closed landfills at the preserve - is bound on the east, west and south by the West Branch.
At one time, the river ran through the middle of the 30-acre site where the landfill now stands, officials said. But in the late 1960s, the alignment of the river was pushed farther south to create room for the landfill operations.
Dan Zinnen, director of resource management and development, told commissioners last week that the realigned river was "poorly designed to begin with."
"With all the development adding more water into the river, we're experiencing severe erosion along the banks of the landfill," Zinnen said.
As a result of the bank erosion, the river has encroached on monitoring wells and gas probes around the perimeter of the landfill.
"We had many probes that were on the verge of falling into the river," Zinnen said.
Officials say steps must be taken to prevent further bank erosion of the landfill, which closed around 1974.
On Tuesday morning, forest preserve commissioners are expected to vote to hire V3 Construction Group for the Mallard Lake channel restoration and stabilization project. If the contract is approved, V3 will be paid $2,474,500 to do the work.
In addition, commissioners are expected to approve a $149,224 contract with WBK Engineering LLC to do construction observation and post-construction monitoring.
Five companies submitted price quotes for the stabilization project, and V3 was the lowest responsible bidder.
Officials say the company has successfully performed numerous projects for the district, including river restoration projects at Springbrook Prairie, West Branch and St. James Farm forest preserves.
Money for the project would come from a roughly $70 million reserve fund earmarked for environmental requirements at the district's landfills.
In addition to Mallard North, the 948-acre Mallard Lake Forest Preserve has a larger landfill to the south that closed in 1999. The district has another closed landfill at Greene Valley Forest Preserve near Naperville.
It's anticipated the river restoration work at Mallard Lake will start in July and be substantially completed by December 2019, officials said. The preserve and its trails are expected to remain open during the project.
Officials wrote in a report for the board that the project "will provide water quality and ecological improvements for the West Branch watershed along with protecting critical infrastructure that serves the residents of Hanover Park."