From McHenry County metadata...The McHenry County areas are comprised of lakes, ponds, rivers, creeks, wetlands, McHenry County Natural Areas Inventory sites, Illinois Natural Areas Inventory sites, oak woodlands, FEMA 100-year flood hazard areas, and Hydrologic Atlas floods of record. These areas were chosen to be included here because they provide, or have the potential to provide, valuable natural functions such as storm water management, aquifer recharge, water filtration, and flora and fauna habitat. Included in this category is a 200-foot buffer around the outside edge of the resource areas with the exception of flood hazard areas and floods of record - McHenry County GIV.

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