Nueces County, TX Environmental Rules: Flood Elevation Requirements (2026)

Article 5, Section B of the county's Flood Damage Prevention Ordinance sets the elevation standard once base flood elevation data exists under Article 3, Section B, Article 4, Section B(8), or Article 5, Section C(3). Paragraph (1) requires new construction and substantial improvement of any residential structure, including manufactured homes sited in mapped zones, to have its lowest floor, including any basement, elevated to or above the base flood elevation; a registered professional engineer, architect, or land surveyor must certify that standard to the Floodplain Administrator as referenced in Article 4, Section C(1)(a).

Paragraph (2) gives nonresidential structures, commercial or industrial, an alternative: floodproof the space below the base flood level so it is watertight with walls able to resist hydrostatic and hydrodynamic loads, again certified by a licensed engineer or architect, with the floodproofed elevation recorded by the Administrator. Paragraph (3) covers enclosed areas below the lowest floor used only for parking, building access, or storage: they must carry at least two openings on separate walls totaling one square inch of net opening per square foot of enclosed area, with the bottom of every opening no more than one foot above grade, so floodwaters can enter and exit automatically.

The ordinance text does not layer an extra freeboard foot onto these elevations in Zone A; it requires the floor at or above the mapped base flood elevation itself, with a separate coastal high-hazard standard applying in V zones.