Baltimore County, MD Environmental Rules: Flood Zones (2026)

Article 32, Title 8 of the County Code implements the National Flood Insurance Program, which Baltimore County joined by resolution effective March 2, 1981. Section 32-8-304(a) makes it unlawful to begin any development wholly or partially within, or in contact with, a Flood Hazard Area established under Section 32-8-105 without first obtaining a county permit; covered work includes filling, grading, new structures, substantial improvement or repair of substantial damage, manufactured-home placement, temporary structures, and watercourse alteration. 04, but the county permit is required regardless. A permit is valid only if actual work starts within 180 days of issuance; the Floodplain Administrator may grant written extensions of up to 90 days at a time on a showing of justifiable cause, so long as the underlying flood hazard mapping under Section 32-8-105 has not changed.

Applications under Section 32-8-305 must include a scaled site plan, the elevation of existing natural ground referenced to the FIRM datum, delineation of the Flood Hazard Area and any floodway, and, for larger subdivisions, hydrologic and hydraulic engineering analyses. The Floodplain Administrator inspects at stake-out, foundation, enclosure, utility, and final stages before a Certificate of Occupancy is released. These Floodplain Management Provisions were most recently rewritten by Bill No. 6-24, effective March 21, 2024, and adopt the 2021 International Building Code Appendix G and ASCE 24-14 by reference.