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

Kane County Code section 9-59, part of the Stormwater Management Ordinance's erosion and sedimentation control article adopted by Ordinance 19-151, limits the area disturbed on any construction site to forty acres at one time, with an additional forty acres, eighty total, allowed only if needed to balance cut and fill; the Administrator can approve a larger phased area if adequate temporary and permanent controls will be maintained. Any applicant disturbing more than one acre must forward a copy of its Notice of Intent under the state's general NPDES permit ILR10 to the county.

Sedimentation basins must be designed for storm frequencies tied to how long the site stays disturbed, from a two-year storm for stabilization under six months up to a ten-year storm for disturbances lasting over a year, and every basin must hold runoff for a minimum ten-hour residence time and release it over twenty-four to forty hours. Stabilization of any area that stops being worked, permanently or for more than fourteen days, must start within one working day and finish within fourteen days, with erosion control blankets or heavy mulch required on ground left idle over winter.

Erosion and sediment control plans must be inspected weekly, or after any rainfall of a half inch or more, under the current IEPA NPDES ILR10 permit, and standards are drawn from the Illinois Urban Manual, the county's Stormwater Technical Manual, or IDOT road and bridge specifications, with the Illinois Urban Manual controlling if the sources conflict.