Century-old Sylvan Lake Dam rebuilt for a safer future

MUNDELEIN – After years of planning and collaboration, the Sylvan Lake Dam in Mundelein has been fully reconstructed to address critical infrastructure needs and protect local waterways and natural resources.

On July 25, officials from the Fremont Township Highway Department, Lake County Stormwater Management Commission, federal legislators and Lake County Board Members joined area residents to celebrate the completion of the newly rebuilt dam.

Lake County SMC prioritized the Sylvan Lake Dam Modification Project due to the structure’s deterioration because the 100-year-old earthen dam had reached the end of its useful life after a century of use. Lake County SMC worked closely for several years with Fremont Township Highway Department and the Sylvan Lake community to get this project to the construction stage and finalized with the assistance of federal funding.

The Sylvan Lake Dam has been updated with modern design standards and high-quality construction materials to withstand more intense storm events and the continued effects of climate change. The project included the relocation of the water main and the previously exposed above-ground sanitary sewer lines along North Highland Drive, which serves 289 homes, installing a new sheet piling wall and reconstruction of the Sylvan Lake Dam and North Highland Drive on top of the dam.

In its previous state, the dam was an environmental risk posed by exposed sanitary sewer lines running through the spillway walls. Relocating the sewers underground was a crucial safety update that significantly reduces the risk of failure and contamination of the area. This is a safeguard not only for the environment, but to ensure the safety of the dam and the cleanliness of the water for residents and wildlife for years to come.

This improvement project also strengthens the community’s infrastructure. These updates will enhance long-term system performance, improve resilience to future hazard events and reduce the risk of environmental harm.

The project received $1.2 million in federal funding through the Federal Emergency Management Agency’s Pre-Disaster Mitigation Congressionally Directed Spending program, administered by the Illinois Emergency Management Agency. Additional funding was provided by the Fremont Township Highway Department and the Sylvan Lake Improvement Association.

Learn more about SMC’s work to improve water quality, reduce flood damage and enhance natural drainage systems at lakecountyil.gov/stormwater.