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

Kendall County's Soil Erosion and Sediment Control subdivision, beginning at Kendall County Code § 16-106, lays out thirteen general principles every development activity in the county has to follow. Erosion and sediment control planning must be part of the initial site design, with a stated preference for reducing erosion rather than just catching sediment after the fact. Development has to follow the site's existing topography and soils to minimize erosion, steep slopes needing high cuts or fills should be avoided, and natural vegetation next to streams, lakes, ponds and wetlands has to be retained and left undisturbed to the extent possible.

Sediment basins, traps, filter barriers and diversions must go in before or at the same time as site clearing and grading begins, and those measures have to be maintained afterward to keep sediment out of runoff. The section requires exposing the smallest practical area of land for the shortest practical time, sizing controls to at least a twenty-five-year storm event, and disposing of all construction waste so wind or water cannot carry it off site; every site must also keep sediment from being tracked onto public or private roads.

Subsection (b) makes clear the county rule layers on top of, and does not relieve, NPDES permit requirements for construction activity. Sec. 16-107 then requires a written Soil Erosion and Sediment Control Plan for every project, and Sec. 16-109 obligates the applicant to inspect and maintain those measures weekly and after every half-inch rain event.