Sandoval County, NM Environmental Rules: Flood Elevation Requirements (2026)

Sec. 18-68, Specific standards, applies wherever base flood elevation (BFE) data has been provided under Sec. 18-5, 18-44(8) or 18-69(c). For residential construction, subsection (1) requires the lowest floor, including any basement, of new construction and substantial improvements to be elevated to one foot or more above the base flood elevation, a one-foot freeboard above the FEMA 1-percent-annual-chance flood line, and a registered professional engineer, architect, or land surveyor must certify to the floodplain administrator that the elevation was met. Nonresidential structures under subsection (2) may instead be floodproofed: the structure and its utilities must be watertight below the BFE, with walls resistant to water passage and components able to resist hydrostatic and hydrodynamic loads, again certified by an engineer or architect and recorded with the floodplain administrator.

Subsection (3) requires any enclosed area below the lowest floor used only for parking, access or storage to have flood vents equalizing hydrostatic pressure, at least two openings on separate walls totaling one square inch of net area per square foot of enclosed floor, with the bottom of each opening no higher than one foot above grade. Manufactured homes placed in Zones A1-30, AH and AE outside an existing park must be elevated on a permanent foundation so the lowest floor sits at or above the BFE and anchored against flotation and lateral movement, while homes in existing manufactured home parks may instead sit on reinforced piers at least 36 inches above grade. Recreational vehicles are exempt only if they stay under 180 consecutive days, are licensed and highway-ready, or meet the same manufactured-home permit standards.