§ 92-15. Standards for all structures.

A. 

Anchoring. New structures and substantial improvement to structures in areas of special flood hazard shall be anchored to prevent flotation, collapse or lateral movement during the base flood. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces.

B. 

Construction materials and methods.

(1) 

New construction and substantial improvements to structures shall be constructed with materials and utility equipment resistant to flood damage.

(2) 

New construction and substantial improvements to structures shall be constructed using methods and practices that minimize flood damage.

(3) 

Enclosed areas.

(a) 

For enclosed areas below the lowest floor of a structure within Zones A1 through A30, AE or AH and also Zone A, if base flood elevation data is available, new and substantially improved structures shall have fully enclosed areas below the lowest floor that are usable solely for parking of vehicles, building access or storage in an area other than a basement and which are subject to flooding designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a licensed professional engineer or architect or meet or exceed the following minimum criteria:

[1] 

A minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided; and

[2] 

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

(b) 

Openings may be equipped with louvers, valves, screens or other coverings or devices, provided that they permit the automatic entry and exit of floodwaters. Enclosed areas subgrade on all sides are considered basements and are not permitted.

C. 

Utilities.

(1) 

Machinery and equipment servicing a building must either be elevated to or above the base flood level or designed to prevent water from entering or accumulating within the components during a flood. This includes heating, ventilating and air-conditioning equipment, hot-water heaters, appliances, elevator lift machinery and electrical junction and circuit breaker boxes. When located below the base flood elevation, a professional engineer's or architect's certification of the design is required.

(2) 

New and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system.

(3) 

New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters. Sanitary sewer and storm drainage systems for buildings that have openings below the base flood elevation shall be provided with automatic backflow valves or other automatic backflow devices that are installed in each discharge line passing through a building's exterior wall.

(4) 

On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.