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Section 8-19 Same--Specific standards.

In all areas of special flood hazard where base flood elevation data have been provided, as set forth in section 8-7, or subsection (9) of section 8-15, the following provisions are required:

(1) Residential construction. New construction or substantial improvement of any residential structure shall have the lowest floor, including basement, elevated no lower than one (1) foot above the base flood elevation. Should solid foundation perimeter walls be used to elevate a structure, openings sufficient to facilitate the unimpeded movements of floodwaters shall be provided in accordance with standards of subsection (3).

(2) Nonresidential construction. New construction or substantial improvement of any commercial, industrial, or nonresidential structure shall have the lowest floor, including basement, elevated no lower than one (1) foot above the level of the base flood elevation. Structures located in all A-zones may be floodproofed in lieu of being elevated provided that all areas of the structure below the required elevation are watertight with walls substantially impermeable to the passage of water, and use structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effect of buoyancy. A registered professional engineer or architect shall certify that the standards of this subsection are satisfied.

(3) Elevated buildings. New construction or substantial improvements of elevated buildings that include fully enclosed areas formed by foundation and other exterior walls below the base flood elevation shall be designed to preclude finished living space and designed to allow for the entry and exit of floodwaters to automatically equalize hydrostatic flood forces on exterior walls.

a. Designs for complying with this requirement must either be certified by a professional engineer or architect or meet the following minimum criteria:

1. Provide a minimum of two (2) openings having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding;

2. The bottom of all openings shall be no higher than one (1) foot above grade; and,

3. Openings may be equipped with screens, louvers, valves or other coverings or devices provided they permit the automatic flow of floodwaters in both directions.

b. Electrical, plumbing, and other utility connections are prohibited below the base flood elevation;

c. Access to the enclosed area shall be the minimum necessary to allow for parking of vehicles (garage door) or limited storage of maintenance equipment used in connection with the premises (standard exterior door) or entry to the living area (stairway or elevator); and

d. The interior portion of such enclosed area shall not be partitioned or finished into separate rooms.

(4) Standards for manufactured homes and recreational vehicles.

a. All manufactured homes placed, or substantially improved, on individual lots or parcels, in expansions to existing manufactured home parks or subdivisions, or in substantially improved manufactured home parks or subdivisions, must meet all the requirements for new construction, including elevation and anchoring.

b. All manufactured homes placed or substantially improved in an existing manufactured home park or subdivision must be elevated so that:

(i) The lowest floor of the manufactured home is elevated no lower than one (1) foot above the level of the base flood elevation, or

(ii) The manufactured home chassis is supported by reinforced piers or other foundation elements of at least an equivalent strength, of no less than thirty-six (36) inches in height above grade.

(iii) The manufactured home must be securely anchored to the adequately anchored foundation system to resist flotation, collapse and lateral movement.

(iv) In an existing manufactured home park or subdivision on which a manufactured home has incurred "substantial damage" as the result of a flood, any manufactured home placed or substantially improved must meet the standards of section 8-19(4)(b)(i) and (iii) above.

c. All recreational vehicles placed on site must either:

(i) Be fully licensed and ready for highway use, or

(ii) The recreational vehicle must meet all the requirements for new construction, including anchoring and elevation requirements of section 8-19(4)(a) or (b)(i) and (iii) above.

A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices and has no permanently attached structures.

(5) Floodways. Located within areas of special flood hazard established in section 8-7 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and has erosion potential, the following provisions shall apply:

a. Prohibit encroachments, including fill, new construction, substantial improvements and other developments unless certification (with supporting technical data) by a registered professional engineer is provided demonstrating that encroachments shall not result in any increase in flood levels during occurrence of the base flood discharge.

b. If subsection (5)a. above is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this section.

c. Prohibit the placement of manufactured homes (mobile homes), except in an existing manufactured homes (mobile homes) park or subdivision. A replacement manufactured home may be placed on a lot in an existing manufactured home park or subdivision provided the anchoring standards of subsection (2) of section 8-18, and the elevation standards of subsection (1) above, are met.

(Ord. of 6-22-87; Ord. of 7-12-93, II)