Berwyn, IL Environmental Rules: Flood Zones (2026)

Section 1042.25 of the Berwyn Code of Ordinances, adopted under the city's Illinois Municipal Code police powers, regulates development in floodplain areas to keep new work from raising flood or drainage hazards for others, to protect new buildings from flood damage, and to keep federally subsidized flood insurance available. It defines a floodplain as any land area susceptible to being inundated by water from any source. Development is defined broadly: demolition, construction, repair or structural alteration of a building, substantial improvement, manufactured home installation, utilities, roads, bridges, culverts, levees, dams, walls or fences, grading, excavating and paving, storage of materials including gas and liquid storage tanks, and channel modifications. Routine maintenance, road resurfacing, gardening and plowing that involve no filling, grading or levee construction are excluded.

No person, firm, corporation or governmental body not exempted by state law can start development without a development permit from the Building Director/Public Works Director, who receives applications on the city's form and examines the plans. Where a development is proposed for a channel or adjacent area of a stream draining one square mile or more, the applicant must first secure a permit from the Illinois Division of Water Resources or a letter stating Permit Not Required. The Director also confirms that required federal and state approvals, including Section 404 of the Federal Water Pollution Control Act Amendments 1972, are in hand.

For a site in a flood prone area, § 1042.25(G) adds a fourth standard beyond the three quoted below: electrical, heating, ventilation, plumbing and air conditioning equipment must be designed or located so water cannot enter or accumulate in the components during flooding. Substantial improvement means work costing 50% or more of the structure's market or assessed value, whichever is less, and substantial damage means restoration costing 50% or more of market value. New and replacement sanitary sewage systems must minimize flood water infiltration.

A hardship variance goes to the Zoning, Planning and Development Commission, which recommends to the City Council. The applicant must show all seven conditions, including that the activity cannot be located outside the floodplain and that the relief is the minimum necessary. The applicant is also warned in writing that flood insurance premiums can rise by up to $25 per $100 of coverage and must acknowledge the risk in writing.