From the Illinois Department of Natural Resources Office of Water Resources:
Chain O’Lakes/Fox River Flood Prone Structure Inventory
Up-to-date structure elevation data is one of the key elements state and local leaders can use to keep communities and their citizens well informed and prepared for flood hazards.
To gather this critical information and examine flood risk in McHenry and Lake Counties, the Illinois Department of Natural Resources Office of Water Resources is working on the Chain O’Lakes/Fox River Flood Prone Structure Inventory Flood Risk Assessment Project.
For the next year starting June 2026, professionally licensed survey crews will collect first floor (front door sill), lowest entry (window well or crawl space vent), and adjacent grade elevations at homes and outbuildings along the Chain O’Lakes/Fox River system.
To collect this information, survey crews will briefly need to walk onto private property and may be seen taking photographs of the survey area. No disruption to private property is anticipated, and no inside access to structures is necessary to complete the work.
As a result of this project, state, county and local community officials will have access to enhanced flood risk information and tools to assist with flood risk communication and decision making regarding land-use in this flood hazard area.
Questions? Contact the Illinois Department of Natural Resources Office of Water Resources, 217-782-4615, Aaron.Rotherham2@Illinois.gov
