(A) Standards of construction. In all areas of special flood hazards, the following standards are required.
(1) Anchoring.
(a) All new construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure.
(b) All manufactured homes shall meet the anchoring standards of division (E) below.
(2) Construction materials and methods.
(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 be constructed using methods and practices that minimize flood damage.
(c) All new construction, substantial improvement and other proposed new development 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.
(d) Require, within Zones AH or AO, that adequate drainage paths around structures on slopes guide floodwaters around and away from proposed or existing structures.
(3) Elevation and floodproofing.
(a) New construction and substantial improvement of any structure shall have the lowest floor, including basement, elevated to or above the
regulatory flood elevation. Non-residential structures may meet the standards of division (A)(3)(c) below. Upon the completion of the structure, the elevation of the lowest floor, including basement, shall be certified by a registered professional engineer or registered land surveyor and provided to the Floodplain Administrator.
(b) New construction and substantial improvement of any structure in Zone AO shall have the lowest floor, including basement, higher than the highest adjacent grade at least one foot higher than the depth number on the FIRM, or at least two feet if no depth number is specified. Non-residential structures may meet the standards in division (A)(3)(c) below. Upon completion of the structure, a registered professional engineer or registered land surveyor shall certify to the Floodplain Administrator that the elevation of the structure meets this standard.
(c) Non-residential construction shall either be elevated in conformance with divisions (A)(3)(a) and (A)(3)(b) above or together with attendant utility and sanitary facilities:
1. Be floodproofed so that below the regulatory flood level the structure is water-tight with walls substantially impermeable to the passage of water;
2. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and
3. Be certified by a registered professional engineer or architect that the standards of this division are satisfied. Such certifications shall be provided to the Floodplain Administrator.
(d) Require, for all new construction and substantial improvements, that fully enclosed areas below the lowest floor that are useable solely for parking of vehicles, building access or storage in an area other than a basement and which are subject to flooding shall be 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 be certified by either a registered professional engineer or architect to meet or exceed the following minimum criteria.
1. A minimum of two openings with a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided.
2. The bottom of all openings shall be no higher than one foot above grade.
3. Openings may be equipped with screens, louvers, valves or other coverings or devices; provided that, they permit the automatic entry and exit of floodwaters.
(e) Manufactured homes shall meet the above standards and also the standards in division (E) below.
(B) Standards for storage of materials and equipment.
(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 is prohibited.
(2) Storage of other material or equipment may be allowed if not subject to major damage by floods, and if firmly anchored to prevent flotation, or if readily removable from the area within the time available after flood warning.
(C) Standards for utilities.
(1) All new or replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the system and discharge from systems into floodwaters.
(2) On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
(3) All new and replacement sanitary sewage systems for development projects in identified floodplain areas shall meet all requirements of the State and/or County Health Departments and shall be designed to minimize or eliminate infiltration of floodwaters. On-site effluent disposal systems shall not be installed wholly or partially within the designated regulatory floodway. On-site waste disposal systems shall be located so as to avoid their impairment during flood conditions as well as to preclude contamination from them during flooding. Waste disposal systems shall not be installed in a regulatory floodway.
(D) Standards for subdivisions.
(1) All preliminary subdivision proposals shall identify the special flood hazard area and the elevation of the base flood.
(2) All final subdivision plans will provide the elevation(s) of proposed structure(s) and pads. If the site is filled above the base flood, the final lowest floor and pad elevation shall be certified by a registered professional engineer or surveyor and provided to the Floodplain Administrator.
(3) All subdivision proposals shall be consistent with the need to minimize flood damage.
(4) All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.
(5) All subdivisions shall provide adequate drainage to reduce exposure to flood hazards.
(E) Standards for manufactured homes. All manufactured homes that are placed or substantially improved shall:
(1) Be elevated so that the bottom of the structural frame or the lowest point of any attached appliances, whichever is lower, is at or above the regulatory flood elevation; and
(2) Be securely anchored to an adequately anchored foundation system to resist flotation, collapse or lateral movement. Methods of anchoring may include, but are not to be limited to, use of over-the-top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces.
(F) Standards for recreational vehicles. All recreational vehicles placed on site will either:
(1) Be on site for fewer than 180 consecutive days, and 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; or
(2) Meet the permit requirements of § 13.6-5 of this code and the elevation and anchoring requirements for manufactured homes in division (E) above (or division (A)(3)(e) above).
(G) Floodways. Located within areas of special flood hazard established in § 13.6-3 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 erosion potential, the following provisions apply:
(1) Prohibit encroachments, including fill, new construction, substantial improvements and other development unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge; and
(2) If division (G)(1) above is satisfied, all new construction and substantial improvements shall comply with all other applicable flood hazard reduction provisions of this section.
(H) Flood-related erosion-prone areas.
(1) The Floodplain Administrator shall require permits for proposed construction and other
development within all flood-related erosion-prone areas as known to the community.
(2) Permit applications shall be reviewed to determine whether the proposed site alterations and improvements will be reasonably safe from flood-related erosion and will not cause flood-related erosion hazards or otherwise aggravate the existing hazard.
(3) If a proposed development is found to be in the path of flood-related erosion or would increase the erosion hazard, such improvements shall be relocated or adequate protective measures shall be taken to avoid aggravating the existing erosion hazard.
(4) (a) Within Zone E on the Flood Insurance Rate Map, a setback is required for all new development from the lake, bay, riverfront or other body of water to create a safety buffer consisting of a natural vegetative or contour strip.
(b) This buffer shall be designated according to the flood-related erosion hazard and erosion rate, in relation to the anticipated “useful life” of structures, and depending upon the geologic, hydrologic, topographic and climatic characteristics of the land. The buffer may be used for suitable open space purposes, such as for agricultural, forestry, outdoor recreation and wildlife habitat areas, and for other activities using temporary and portable structures only.
(Ord. 2012-04, passed 12-5-2012)