§ 335-5 Provisions for Flood Hazard Reduction

335-5. Provisions for Flood Hazard Reduction.

(a) Construction Standards in Areas of Special Flood Hazard. In all areas of special flood hazards, the following standards are required:

(A) All new construction and substantial improvement shall be anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.

(B) All manufactured homes shall meet one (1) of the anchoring standards of subsection (e) of this section.

(A) All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

(B) All new construction and substantial improvements shall use methods and practices that minimize flood damage.

(C) All new construction and substantial improvements shall be constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.

Exception: Electrical equipment serving nonstructural facilities need not be elevated above the base flood elevation; provided the height to the top of the meter socket enclosure shall be seventy-two (72) inches above grade.

(D) All elements that function as part of the structure, such as furnace, hot water heater, air conditioner, etc., should be elevated to or above the base flood elevation or depth number specified on the FIRM.

(E) All new construction and substantial improvement within Zone AH or AO shall be constructed so that there are adequate drainage paths around structures on slopes to guide flood waters around and away from proposed structures.

(A) New construction and substantial improvement of any structure in a special flood hazard area (SFHA) shall have the lowest floor, including basement, elevated to one (1) foot above the base flood elevation. Nonresidential structures may meet the standards in subsection (a)(3)(D) of this section. Upon completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor or verified by the local building inspector to meet elevation requirements.

Notification of compliance shall be recorded as set forth in Section 335-4(c)(3)(A).

(B) New construction and substantial improvement of any structure in an area of shallow flooding or a zone designated AO on the FIRM map shall have the lowest floor, including basement, elevated to one (1) foot above the depth number on the FIRM. If there is no depth number on the FIRM, the lowest floor, including basement, shall be elevated at least three (3) feet above the highest adjacent grade. Nonresidential structures may meet standards in subsection (a)(3)(D) of this section. Upon completion of the structure, compliance with the elevation requirement shall be certified by a registered professional engineer or surveyor or verified by the Director. Notification of compliance shall be recorded as provided by Section 335-4(c)(3)(B).

(D) Nonresidential construction shall either be elevated in conformance with subsection (a)(3)(A) or (a)(3)(B) of this section, or, together with attendant utility and sanitary facilities:

1. Be floodproofed so that one (1) foot above the base flood level the structure is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.

2. Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the Director as provided by subsection (a)(3)(B) of this section.

(E) Fully enclosed areas below the lowest floor shall be designed to automatically equalize the hydrostatic flood forces on exterior walls by allowing for the entry and exit of flood waters. Designs must be certified by a registered professional engineer or architect or have at least two (2) openings with a total net area of at least one (1) square inch per square foot of flooded area. The openings shall be no more than one (1) foot above grade.

a. A garage attached to a residential structure constructed with the garage floor slab below the BFE must be designed to allow for automatic entry of flood waters, see subsection (a)(3)(E) of this section. Areas of the garage below the BFE must be constructed with flood resistant materials, see subsection (a)(2) of this section.

b. A garage attached to a nonresidential structure must meet the above requirements or be dry floodproofed.

2. Detached garages and accessory structures with the lowest floor below the base flood elevation will require a variance per Section 335-8.

(4) Exceptions for Temporary Structures. The Building Official is authorized to issue a permit for a temporary structure that does not meet the requirements of subsections (a)(1) through (a)(3) of this section, provided the temporary structure is:

(A) Constructed of materials that are easily removable; and

(B) Removed from the areas of special flood hazard each flood hazard season (between October 15th and April 15th).

The permit for a temporary structure shall not be permitted for more than one hundred eighty (180) days. The Building Official is authorized to grant extensions for demonstrated cause.

(b) Standards for Storage of Materials and Equipment. After the effective date of this chapter, application for new storage in areas designated on FIRM or Flood Boundary Maps shall meet the following criteria:

(1) The storage or processing of materials that are in time of flooding buoyant, flammable, explosive, or could be injurious to human, animal or plant life are generally prohibited.

(2) Storage of other material or equipment may be allowed if not subject to major damage by floods and firmly anchored to prevent flotation or if readily removable from the area within the time available after flood warning.

(1) All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the system and discharge from the system into flood waters.

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

(d) Standards for Subdivisions and Other Proposed Development. See Section 322-4 for subdivision requirements.

(1) All new subdivision proposals and other proposed development, including proposals for manufactured home parks and subdivisions, greater than fifty (50) lots or five (5) acres, whichever is the lesser shall:

(A) Identify the special flood hazard areas (SFHA) and base flood elevations (BFE).

(B) Identify the elevations of the lowest floors of all proposed structures and pads on the final plans.

(C) If the site is filled above the base flood elevation, the following as-built information for each structure shall be certified by a registered civil engineer or licensed land surveyor and provided as part of an application for a letter of map revision based on fill (LOMR-F) to the Floodplain Administrator:

1. Lowest floor elevation.

2. Pad elevation.

3. Lowest adjacent grade.

(2) All subdivision proposals and other proposed development shall be consistent with the need to minimize flood damage.

(3) All subdivision proposals and other proposed developments shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.

(4) All subdivision proposals and other proposed developments shall be provided adequate drainage to reduce exposure to flood hazards.

(1) All manufactured homes that are placed or substantially improved within Zones A, A1-30, AO, AH, and AE on the community’s Flood Insurance Rate Map, on sites located:

(A) Outside of a manufactured home park or subdivision;

(B) In a new manufactured home park or subdivision;

(D) In an existing manufactured home park or subdivision on a site upon which a manufactured home has incurred “substantial damage” as the result of a flood shall be elevated on a designed permanent foundation system so that the lowest floor of the manufactured home is elevated to one (1) foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement. For manufactured homes that are placed or substantially improved within Zones V, V1-30 and VE on the community’s Flood Insurance Rate Map the requirements of Section 335-7 shall be met.

(2) All manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within Zones A, A1-30, AO, AH, AE, V, V1-30 and VE on the community’s Flood Insurance Rate Map that are not subject to the provisions of subsection (e)(1) of this section will be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement and be elevated so that either the:

(A) Lowest floor of the manufactured home is one (1) foot above the base flood elevation; or

(B) Manufactured home chassis is supported on a designed foundation system by reinforced piers or other foundation elements of at least equivalent strength that are no less than thirty-six (36) inches in height above grade.

Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered civil engineer or licensed land surveyor, and verified by the community building inspector to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator.

(3) The developer responsible for the plan, the installer or State agency responsible for regulating manufactured home placement shall certify that the manufactured home complies with this section. The certificate shall be filed with the Director as required by Section 335-4(c)(3)(E).

(1) All recreational vehicles placed on sites within Zones A, A1-30, AO, AH, AE, V, V1-30 and VE on the community’s Flood Insurance Rate Map will:

(A) Be on the site for fewer than one hundred eighty (180) days annually; and

(B) Limit placement of unit to the period of May 1st to October 29th; and

(C) Be fully licensed and ready for highway use. 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 additions; and

(D) Standards for permanent equipment and utilities shall be as required in this section.

(2) Recreation vehicles on sites within Zones V, V1-30 and VE on the community’s Flood Insurance Rate Map will meet the requirements of subsection (f)(1) of this section and Section 335-7. (Ord. 1541, § 4, 7/13/1982; Ord. 1746, § 2, 7/15/1986; Ord. 2102, §§ 9, 11, 1/9/1996; Ord. 2560, § 1, 10/4/2016; Ord. 2603, § 1, 6/26/2018)