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A. Standards Of Construction: In all areas of special flood hazard the following standards are required:
a. All new construction and substantial improvements shall be adequately 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 the anchoring standards of subsection D of this section.
2. Construction Materials And Methods: All new construction and substantial improvements, including manufactured homes, shall be constructed:
a. With flood resistant materials, and utility equipment resistant to flood damage for areas below the base flood elevation;
b. Using methods and practices that minimize flood damage;
c. 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; and
d. If within zones AH or AO, so that there are adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures.
3. Elevation And Floodproofing:
a. Residential Construction: Residential construction, new or substantial improvement, shall have the lowest floor, including basement:
(1) In an AO zone, elevated above the highest adjacent grade to a height exceeding the depth specified in feet on the FIRM by at least one foot (1'), or elevated at least three feet (3') above the highest adjacent grade if no depth number is specified.
(2) In an A zone, elevated at least one foot (1') above the base flood elevation, as determined by the city.
(3) In all other zones, elevated at least one foot (1') above the base flood elevation.
Upon the 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 city engineer or city building official to be properly elevated. Such certification or verification shall be provided to the floodplain administrator.
b. Nonresidential Construction: Nonresidential construction shall either be elevated to conform with subsection A3a of this section or together with attendant utility and sanitary facilities:
(1) Be floodproofed below the elevation recommended under subsection A3a of this section so that the structure is watertight 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 subsection A3b are satisfied. Such certification shall be provided to the floodplain administrator.
c. Flood Openings: All new construction and substantial improvement with fully enclosed areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building access or storage, 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 floodwater. Designs for meeting this requirement must exceed the following minimum criteria:
(1) Be certified by a registered professional engineer or architect; or
(2) For nonengineered openings:
(A) Have a minimum of two (2) openings on different sides having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding.
(B) The bottom of all openings shall be no higher than one foot (1') above grade.
(C) Openings may be equipped with screens, louvers, valves or other coverings or devices provided that they permit the automatic entry and exit of floodwater.
(D) Buildings with more than one enclosed area must have openings on exterior walls for each area to allow floodwater to directly enter.
d. Manufactured Homes: Manufactured homes shall also meet the standards in subsection D of this section.
B. Standards For Utilities:
1. All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate:
a. Infiltration of floodwaters into the systems; and
b. Discharge from the systems into floodwaters.
2. On site waste disposal systems shall be located to avoid impairment to them, or contamination from them, during flooding.
C. Standards For Subdivisions And Other Proposed Development:
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 lesser, shall:
a. Identify the special flood hazard area (SFHA) and the base flood elevation (BFE).
b. Identify the elevations of 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.
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 development shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.
4. All subdivisions and other proposed development shall provide adequate drainage to reduce exposure to flood hazards. (Ord. 2012-003, 9-11-2012)
D. Standards For Manufactured Homes:
1. All manufactured homes that are placed or substantially improved within zones A1-30, 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,
c. In an expansion to an existing manufactured home park or subdivision, or
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 permanent foundation such that the lowest floor of the manufactured home is elevated at least one foot (1') above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.
2. All manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within zones A1-30, AH, AE, V1-30, V and VE on the community's flood insurance rate map that are not subject to the provisions of subsection D1 of this section will be elevated so that either the:
a. Lowest floor of the manufactured home is elevated at least one foot (1') above the base flood elevation, or
b. Manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than thirty six inches (36") in height above grade and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.
E. Standards For Recreational Vehicles:
1. All recreational vehicles placed on sites within zones A1-30, AH and AE on the community's flood insurance rate map will either:
a. Be on the site for fewer than one hundred eighty (180) consecutive days;
b. 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
c. Meet the permit requirements of section 12-1-4 of this chapter and the elevation and anchoring requirements for manufactured homes in subsection D1 of this section.
2. Recreational vehicles placed on sites within zones V1-30, V and VE on the community's flood insurance rate map will meet the requirements of subsection E1 of this section.
F. Floodways: Located within areas of special flood hazard established in subsection 12-1-3B of this chapter 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 improvement and other new development unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in the base flood elevation during the occurrence of the base flood discharge.
2. If subsection F1 of this section is satisfied, all new construction, substantial improvement and other proposed new development shall comply with all other applicable flood hazard reduction provisions of this section.
G. 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 improvement is found to be in the path of flood related erosion or would increase the erosion hazard, such improvement shall be relocated or adequate protective measures shall be taken to avoid aggravating the existing erosion hazard.
4. Within zone E on the flood insurance rate map, a setback is required for all new development from the riverfront or other body of water to create a safety buffer consisting of a natural vegetative or contour strip. 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. 95-001, 2-14-1995)