Georgetown, TX Environmental Rules: Flood Elevation Requirements (2026)

City Code Sec. 160 sets the specific construction standards that apply once base flood elevation data exists for a site. Under Subsection A, new construction and substantial improvement of any residential structure must have the lowest floor, including any basement, elevated at least 12 inches above the base flood elevation, and a registered professional engineer, architect, or land surveyor must certify that standard to the Floodplain Administrator. Subsection B gives commercial, industrial, and other nonresidential buildings a choice: elevate the lowest floor the same 12 inches, or floodproof the structure below that level so walls are substantially impermeable and can resist hydrostatic and hydrodynamic loads, with a licensed engineer or architect certifying the design and the specific elevation to which the building is floodproofed.

Enclosures below the lowest floor used only for parking, access, or storage must equalize hydrostatic pressure through at least two openings on separate walls totaling one square inch of net area per square foot of enclosed space, with opening bottoms no higher than one foot above grade (Subsection C). Manufactured homes placed on sites in flood zones A1-30, AH, and AE must likewise be elevated on a permanent foundation so the lowest floor sits at least 12 inches above base flood elevation and is anchored against flotation, collapse, and lateral movement (Subsection D).

The Floodplain Administrator, a role held by the Director/Building Official of Inspection Services under Sec. 110, reviews and maintains the elevation certifications required under this section as part of the development permit process established in Sec. 050.