Harford County, MD Environmental Rules: Flood Elevation Requirements (2026)

Code Section 131-8 defines FLOOD PROTECTION ELEVATION as the base flood elevation plus 2 feet of freeboard, explaining that freeboard is a factor of safety that compensates for uncertainty in factors that could contribute to flood heights greater than the height calculated for a selected size flood and floodway conditions, such as wave action, obstructed bridge openings, debris and ice jams, climate change and the hydrologic effect of urbanization in a watershed. Section 131-31, governing residential structures and residential portions of mixed-use buildings, applies that definition directly: lowest floors shall be elevated to or above the flood protection elevation.

In Zone AO shallow-flooding areas, the lowest floor instead has to sit at least as high as the FIRM's depth number plus 2 feet, or 4 feet if no depth number is shown. Base flood elevations and the special flood hazard areas that trigger these rules come from the Flood Insurance Study for Harford County dated April 19, 2016 and its accompanying Flood Insurance Rate Maps, kept on file at the Department of Planning and Zoning under Section 131-3. Under Section 131-11, it is unlawful to begin any development in a flood hazard area, including filling, grading, new construction or substantial improvement, without first obtaining a County permit; the Director of Planning and Zoning serves as the Floodplain Administrator who reviews and issues those permits under Section 131-9.

Owners who cannot meet the elevation standard can apply to the Directors for a variance under Sections 131-41 through 131-44, but only on a showing of exceptional hardship tied to the physical characteristics of the lot; increased cost or inconvenience alone does not qualify.