§ 18-72. Specific standards.

In all areas of special flood hazard designated as A1-30, AE, AH, A (with engineered or estimated base flood elevation), the following provisions are required:

(1)

Residential and non-residential structures. Where base flood elevation data is available, new construction and substantial improvement of any structure or manufactured home shall have the lowest floor, including basement, elevated no lower than one 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 flood waters shall be provided in accordance with standards of subsection 18-72(3).

(2)

Non-residential structures. New construction and substantial improvement of any non-residential structure located in A1-30, AE, or AH zones, may be floodproofed in lieu of elevation. The structure, together with attendant utility and sanitary facilities, must be designed to be water tight to one foot above the base flood elevation, with walls substantially impermeable to the passage of water, and 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 design and methods of construction are in accordance with accepted standards of practice for meeting the provisions above, and shall provide such certification to the official as set forth above and in subsection 18-53(6).

Dry floodproofing is allowed only where flood velocities are less than or equal to five feet per second. A registered professional engineer or architect shall certify that the standards of this subsection are satisfied. A flood emergency operation plan and an inspection and maintenance plan must be provided by the design professional for the building. Such certification shall be provided to the floodplain administrator.

(3)

Enclosures for elevated buildings. All new construction and substantial improvements of existing structures that include any fully enclosed area below the base flood elevation, located below the lowest floor formed by the foundation and other exterior walls shall be designed so as to be an unfinished or flood resistant enclosure. The enclosure shall be designed to equalize hydrostatic flood forces on exterior walls by allowing for the automatic entry and exit of flood waters.

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 openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding (if a structure has more than one enclosed area below the base flood elevation, each shall have openings on exterior walls);

2.

The bottom of all openings shall be no higher than one foot above grade; and

3.

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

b.

So as not to violate the "lowest floor" criteria of this chapter, the unfinished or flood resistant enclosure shall only be used for parking of vehicles, limited storage of maintenance equipment used in connection with the premises, or entry to the elevated area.

c.

The interior portion of such enclosed area shall not be partitioned or finished into separate rooms. All interior walls, ceilings and floors below the base flood elevation shall be unfinished and/or constructed of flood resistant materials.

d.

Mechanical, electrical or plumbing devices shall not be installed below the base flood elevation. The interior portion of such enclosed area(s) shall be void of utilities except for essential lighting and power as required.

e.

Property owners shall be required to execute a flood openings/venting affidavit acknowledging that all openings will be maintained as flood vents, and that the elimination or alteration of the openings in any way will violate the requirements for enclosures below the base flood elevation. Periodic inspections will be conducted by the floodplain administrator to ensure compliance.

f.

Property owners shall agree, certify, and declare to the following conditions and restrictions placed on the affected property as a condition for granting a permit. A binding agreement, referred to as a non-conversion agreement, is required to be executed and recorded with the deed. It shall obligate the owner to the following terms and conditions:

1.

That the enclosed area(s) shall remain fully compliant with all parts of the section enclosures for elevated buildings of this chapter unless otherwise modified to be fully compliant with the applicable sections of the flood damage prevention ordinance in effect at the time of conversion.

2.

A duly appointed representative of the town is authorized to enter the property for the purpose of inspecting the exterior and interior of the enclosed area to verify compliance with the agreement and permit.

3.

The community may take any appropriate legal action to correct any violation pertaining to the agreement and the subject permit.

(4)

Standards for manufactured homes and recreational vehicles. Where base flood elevation data are available:

a.

All manufactured homes placed and substantially improved on:

1.

Individual lots or parcels,

2.

In new or substantially improved manufactured home parks or subdivisions,

3.

In expansions to existing manufactured home parks or subdivisions, or

4.

On a site in an existing manufactured home park or subdivision where a manufactured home has incurred "substantial damage" as the result of a flood, must have the lowest floor including basement elevated no lower than one foot above the base flood elevation.

b.

Manufactured homes placed and substantially improved in an existing manufactured home park or subdivision may be elevated so that either:

1.

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

2.

Where no base flood elevation exists, the manufactured home chassis and supporting equipment is supported by reinforced piers or other foundation elements of at least equivalent strength and is elevated to a maximum of 60 inches (five feet) above grade.

c.

All manufactured homes must be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.

d.

All recreational vehicles placed on sites must either:

1.

Be on the site for fewer than 180 consecutive days, fully licensed and ready for highway use if it is licensed, on its wheels or jacking system, attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached structures or additions; or

2.

The recreational vehicle must meet all the requirements for "New Construction," including the anchoring and elevation requirements of subsection 18-72(3)a. and (3)c.

(5)

Require, until a regulatory floodway is designated, that no new construction, substantial improvements, or other development (including fill) shall be permitted within zones A1-30 and AE on the town FIRM, unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the water surface elevation of the base flood more than one foot at any point within the community.

(6)

Accessory structures (also referred to as appurtenant structures). This provision generally applies to new and substantially improved accessory structures. When an accessory structure complies with all other provisions of this chapter (including floodway encroachment), represents a minimal investment (less than $1,000.00) and meets the requirements outlined below, these structures may be wet-floodproofed and do not have to be elevated or dry floodproofed.

Accessory structures include, but are not limited to, residential structures such as detached garages, storage sheds for garden tools or woodworking, gazebos, picnic pavilions, boathouses, small pole barns, and similar buildings. The following provisions apply to accessory structures built below the base flood elevation:

a.

A permit shall be required prior to construction or installation.

b.

Must be low value (less than $1,000.00) and not be used for human habitation.

c.

Use must be restricted to parking of personal vehicles or limited storage (low-cost items that cannot be conveniently stored in the principal structure).

d.

Must be designed with an unfinished interior and constructed with flood damage-resistant materials below the BFE.

e.

Must be adequately anchored to prevent flotation, collapse, or lateral movement.

f.

Must have adequate flood openings as described in subsection 18-71(5) and be designed to otherwise have low flood damage potential.

g.

Shall be constructed and placed on the building site so as to offer the minimum resistance to the flow of floodwaters.

h.

Any mechanical and other utility equipment in the structure must be elevated to or above the BFE or must be floodproofed.

i.

Under limited circumstances communities may issue variances to permit construction of wet-floodproofed accessory structures. Communities should not grant variances to entire subdivisions for accessory structures, especially detached garages. Variances should only be reviewed and issued on an individual or case-by-case basis and be based on the unique characteristics of the site.

j.

If located in a V zone, the structure must be elevated on posts, piles, piers, or columns; consistent with all V zone building standards.

(Ord. No. 2018-9 , Art. 4(§ B), 8-6-2018)