Cook County, IL Environmental Rules: Flood Zones (2026)
FEMA flood zone rules in Cook County, IL, also called floodplain regulations or special flood hazard area (SFHA) rules, determine flood insurance requirements and elevation standards for new construction.
Key Facts
- Design Storm
- 100-year event
- MWRD
- Countywide stormwater
- NFIP
- Flood insurance required
- Ordinance
- Floodplain Ordinance
Summary
Cook County has a Floodplain Ordinance governing development in FEMA-designated flood zones. The Metropolitan Water Reclamation District's Watershed Management Ordinance establishes countywide stormwater and floodplain standards including 100-year event design.
On July 29, 2019, the Cook County Board of Commissioners approved an ordinance adopting new regulatory codes. Cook County Codes 2023 — More information: Water and Sewage – Plumbing Code; Amendments to Plumbing Code; Electrical Code [...] Amendments to Electrical Code; International Code Council – Purchase the ICC Codes online; Chapter 102- Building and Building Regulations; Chapter 32-FEES; Energy Benchmarking Report; Illinois Accessibility Code (effective April 24, 1997); 2021 International Energy Conservation Code. Cook County Zoning Ordinance — Ord. No. 01-O-30, as adopted by the County Board on November 6, 2001. [...] The Cook County Zoning Ordinance was most recently amended in 2003. Included sections are: Cook County Zoning Ordinance of 2003; Floodplain Ordinance for Cook County; Cook County Subdivision Manual; Tree Preservation, Landscaping and Screening; Wireless; [...] Billboard and Off-Premise Outdoor Advertising Sign Ordinance of Cook County.
Full Breakdown
Cook County's Floodplain Ordinance regulates construction in FEMA-designated flood zones within unincorporated areas. The Metropolitan Water Reclamation District (MWRD) Watershed Management Ordinance, authorized by 70 ILCS 2605, establishes comprehensive countywide stormwater management regulations covering drainage, detention, floodplain management, wetlands, soil erosion, sediment control, water quality, and riparian area management. The design standard is the 100-year (1% annual chance) storm event. New construction in flood zones must be elevated above the base flood elevation. FEMA Flood Insurance Rate Maps (FIRMs) identify flood hazard areas. Properties in Special Flood Hazard Areas must maintain flood insurance through the National Flood Insurance Program (NFIP). Cook County participates in the NFIP Community Rating System for reduced insurance premiums.
Violations & Fines
Building in flood zone without compliance: stop-work order, $100–$1,000 fine. NFIP non-compliance: loss of flood insurance eligibility.
Frequently Asked Questions
Can I build in a flood zone in Cook County?
Who manages flood regulations in Cook County?
Sources & Official References
Other rules in Cook County
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