Lake County, Illinois: drinking water report. Lake County occupies the northeastern corner of Illinois, home to about 710,000 residents in suburbs north of…
Lake County occupies the northeastern corner of Illinois, home to about 710,000 residents in suburbs north of Chicago. Most communities draw from Lake Michigan, purchasing water wholesale from the Central Lake County Joint Action Water Agency, the city of Waukegan, or other Lake Michigan permittees. Some western communities rely on groundwater from deep aquifers.
Lake Michigan source water is generally clean, but Lake County hosts Naval Station Great Lakes – the US Navy's only boot camp – which has documented PFAS contamination from AFFF use. The contamination affects groundwater near the installation in North Chicago.
According to the Illinois EPA's 2024 monitoring data, three Lake County water systems reported PFAS above detection thresholds, all in communities near Naval Station Great Lakes or other industrial facilities. UCMR5 data confirms these detections. Communities on Lake Michigan surface water show lower PFAS levels than those using supplemental groundwater.
Most Lake County residents on Lake Michigan water benefit from a clean source. Groundwater communities near Naval Station Great Lakes should track PFAS data closely.
Check your water to confirm your source and see monitoring data. For PFAS concerns, activated carbon or reverse osmosis filters provide household protection. Our water filter guide covers options. Pull your detailed report, and visit our Illinois page for statewide data.