McHenry County, IL Environmental Rules: Erosion Control (2026)

060(A), every regulated development, other than work covered by a General Permit, must control erosion at the source rather than just downstream. Control measures must meet the minimum standards of the Illinois Urban Manual. Perimeter control, silt fencing or an equivalent measure, is required wherever a tributary area exceeds 5,000 square feet and runoff moves in sheet flow; an acceptable vegetated filter strip must be at least 25 feet wide and covered by native plants, turf grass or other vegetation on 70% or more of the ground.

Slopes steeper than 3:1 must be stabilized with staked sod or an erosion control blanket combined with seeding. Stockpiled soil in flood hazard areas has to be cleared out at the end of every work day, and any dewatering discharge must run through a sediment trap after the Enforcement Officer is notified. Temporary erosion and sediment control measures must come out within 30 days of final stabilization, with trapped sediment removed and the ground permanently stabilized. Development that disturbs 1 acre or more, plus all Major Access, Public Road, Mining, Flood Hazard Area and Wetland development, additionally must meet IEPA General NPDES Permit No.

ILR10 and install a stabilized construction entrance so mud is not tracked onto public roads. 100, and can inspect a site at any stage, issue a stop-work order, or require an after-the-fact permit for unauthorized disturbance.