Madison County, IL Fence Regulations: Retaining Walls (2026)

Two separate chapters touch retaining walls. 080(D) of the zoning code bars any permanent fence, retaining wall, or obstruction within a public street or alley right-of-way unless the Building and Zoning Committee authorizes it; a wall built on a public easement or across a ditch must be constructed so it does not block drainage, and the wall's owner is responsible for removing or replacing it whenever maintenance or another need requires. 133 of the stormwater drainage chapter caps how much grading or filling a property owner can do near a property line: no change in topography within 25 feet of the line can create a slope steeper than five horizontal to one vertical, and a 5-foot grassy buffer along the property line must stay free of fill.

A retaining wall is the code's built-in exception to that slope cap, but only if the abutting property owner gives written consent and both the Planning Commission and the County Board approve the wall. Grading and fill work more broadly runs through Chapter 114's fill-permit process: a fill permit application must show existing elevations, the fill route, quantity, and erosion-control method, neighboring owners are notified, and the Building and Zoning Department collects a $75 flat permit fee before work begins.