Lakewood, CA Environmental Rules: Flood Elevation Requirements (2026)

C sets three elevation paths for new residential construction, including manufactured homes, in the special flood hazard area. In the AR Zone with a base flood depth listed on the Flood Insurance Rate Map, the lowest floor must be elevated above the highest adjacent grade to at least that depth number, or at least two feet above grade if no depth number is shown. In the AR Zone generally, the required elevation is the lower of the AR base flood elevation or three feet above the highest adjacent grade.

A new manufactured home must be securely fastened to an anchored foundation and either meet those same floor elevations or sit on reinforced piers at least thirty-six inches above grade. Once built, a registered professional engineer or surveyor must certify the lowest floor's elevation, and a City building inspector must verify it before the Floodplain Administrator will accept the project as compliant. 2: instead of elevating, it can be floodproofed below the required elevation so the structure is watertight, with a registered engineer or architect certifying the floodproofing meets the standard.

Enclosed areas below the lowest floor that are used only for parking, access, or storage need at least two openings totaling one square inch of net area per square foot of enclosed space, with the lowest opening no higher than one foot above grade, unless an engineer certifies an equivalent design, so floodwater can enter and exit without damaging the structure.