Sec. 32-141

Floodplain

• Maximum accessoryAccessory useA secondary activity customarily incidental to the main use of the lot — a garage, a home office. structure area in SFHA600 sqftsq ftSquare feet. An acre is 43,560 sq ft; a typical suburban lot is 7,000–10,000.

  Be limited to no more than 600 square feet in total floor area;

• Maximum heightMaximum heightThe tallest a building may be, given in feet, in storeys, or both — whichever binds first. of flood opening bottom1 ft above grade

  The bottom of all required openings shall be no higher than one foot above the adjacent grade.

• Flood opening ratio1 sq inch per sq ftsq ftSquare feet. An acre is 43,560 sq ft; a typical suburban lot is 7,000–10,000.

  The total net area of all openings must be at least one square inch for each square foot of enclosed area subject to flooding.

• Floodproofing elevation for non-residential structures2 ft above BFE

  Non-residential buildings located in all A1-30, AE, and AH zones may be floodproofed in lieu of being elevated provided that all areas of the building components below the elevation corresponding to the BFE plus two feet are watertight...

• Lowest floor elevation for non-residential structures18 inches above BFE

  New construction or substantial improvement of any commercial, industrial, or non-residential building (or manufactured home) shall have the lowest floor, including basement, elevated to or above the base flood level plus 18 inches.

• Lowest floor elevation for residential structures18 inches above BFE

  New construction or substantial improvement of any residential structure (including manufactured homes) in Zones A1-30, AE, AH, and A with detailed base flood elevations shall have the lowest floor, including basement, elevated to or above the base flood level plus 18 inches.

• Permit required in floodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions.

  All uses, activities, and development occurring within any floodplain district, including placement of manufactured homes, shall be undertaken only upon the issuance of a permit.

• Maximum days for recreational vehicle on site180 days

  Be on the site for fewer than 180 consecutive days, be fully licensed and ready for highway use...

• Subdivision area threshold for BFE data5 acresacre43,560 square feet — about the size of an American football field without the end zones.

  Base flood elevation data shall be obtained from other sources or developed using detailed methodologies, hydraulic and hydrologic analysis, comparable to those contained in a Flood Insurance Study for subdivision proposals and other proposed development proposals (including manufactured home parks and subdivisions) that exceed 50 lots or five acres, whichever is the lesser.

• Subdivision lot threshold for BFE data50 lots

  Base flood elevation data shall be obtained from other sources or developed using detailed methodologies, hydraulic and hydrologic analysis, comparable to those contained in a Flood Insurance Study for subdivision proposals and other proposed development proposals (including manufactured home parks and subdivisions) that exceed 50 lots or five acres, whichever is the lesser.

• Substantial improvement threshold50 pct of structure value

  The change, when added to all the changes made during a rolling five-year period does not constitute 50 percent of the structure's value.