(A) A minimum building floor elevation shall be eight inches above the design high water elevation in the case of on-site retention or combination storage. In the case of retention basins, the minimum building floor elevation shall be eight inches above the back of the curb fronting the lot.
(B) The provisions of this section shall not apply to any existing building or structure, nor to an expansion of less than 25% in floor area or any alteration to an existing building or structure, but in no case shall the floor elevation of the extension be below the existing floor of habitable space.
(Ord. 21-11, passed 10-26-2021)