Environmental Rules in Naperville, IL

If you live in Naperville or are thinking about moving there, environmental rules are one of those things you probably won't think about until they affect you directly. Naperville has 3 specific rules on the books covering different aspects of environmental rules, and some of them might surprise you.

Erosion Control

Naperville requires a detailed, engineer-sealed grading plan before issuing a building permit for a new home or addition on any lot without an approved master grading plan.

Key details: Governing section: City Code § 5-2B-7. Plan preparer: Illinois-registered professional engineer. Minimum yard slope: 1.5% side and rear drainage. Trigger: New home or addition permit.

Building without an approved, engineer-sealed grading plan can block issuance of the building or occupancy permit, and non-conforming grading discovered later must be corrected at the owner's expense.

Flood Zones

Naperville doesn't write its own floodplain code - City Code § 5-6-1 adopts the DuPage Countywide Stormwater and Floodplain Ordinance by reference for the city's DuPage County area, with a separate Will County ordinance covering the rest.

Key details: DuPage area rule: DuPage Countywide Stormwater/Floodplain Ordinance. Will County area rule: Will County Stormwater Management Ordinance. DuPage ordinance effective: May 14, 2019. Copy on file: City Engineer's office.

Developing in a mapped flood hazard area without following the adopted county ordinance is a code violation enforced through the City Engineer's office; the specific permit and penalty terms are set out in the adopted DuPage or Will County ordinance itself, on file at City Hall.

Stormwater Management

Naperville requires storm water systems to follow the City's Design Manual for Public Improvements and bars grading, earthmoving, or new storm water structures on covered property except as shown on approved final engineering plans.

Key details: Design standard: City Design Manual for Public Improvements. Plan changes: Unlawful without City Engineer approval. Correction window: 10 days after notice of violation. Appeal body: Building Review Board.

Noncompliance is enforceable by the City Engineer, who can demand correction within 10 days of notice; owners may appeal to the Building Review Board, though the City can act at once if a condition threatens flooding or flash-runoff damage.

The Bottom Line

Naperville's environmental rules rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Naperville is broadly strict or permissive.

Keep in mind that Naperville can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, where we track updates as they happen.