The City Clerk, in reviewing all applications for new construction, substantial improvements, prefabricated buildings, placement of manufactured homes and other development(s) (as defined in § 153.02), will:
(A) Obtain, review, and reasonably utilize, if available, any regulatory flood elevation data and floodway data available from federal, state, or other sources, until such other data is provided by the Federal Insurance Administration in a flood insurance study; and require within special flood hazard areas on the official map that the following performance standards be met.
(1) Until a floodway has been designated, no development or substantial improvement may be permitted within the identified floodplain unless the applicant has demonstrated that the proposed development or substantial improvement, when combined with all other existing and reasonably anticipated developments or substantial improvements, will not increase the water surface elevation of the 100-year flood more than one foot at any location.
(2) New construction or substantial improvement of any residential structure shall have the lowest floor, including basement, elevated at least one foot above the base flood elevation.
(3) New construction or substantial improvement of any commercial, industrial, or other nonresidential structure shall have either the lowest floor, including basement, elevated at least one foot above the base flood elevation or, together with attendant utility and sanitary facilities, be flood-proofed so that below such a level the structure is water-tight 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. A registered professional engineer or architect shall certify that the standards of this division (A)(3) are satisfied. Such certification shall be provided to the local administrator.
(4) Fully enclosed areas below the lowest floor that are usable 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 either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria: 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 shall be provided. The bottom of all openings shall be no higher than one foot above grade. Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.
(5) Appurtenant structures used exclusively for storage of motor vehicles and storage of other items readily removable in the event of a flood warning may have their lowest floor below one foot above the base flood elevation provided the structure is capable of withstanding hydrostatic and hydrodynamic forces caused by the base flood and provided that no utilities are installed in the structure except elevated or flood-proofed electrical fixtures. If the structure is converted to another use, it must be brought into full compliance with the minimum standards governing such use.
(B) Require the use of construction materials that are resistant to flood damage;
(C) Require the use of construction methods and practices that will minimize flood damage;
(D) Require that new structures be designed (or modified) and adequately anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy;
(E) New structures 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;
(F) Assure that all manufactured homes shall be anchored to resist flotation, collapse, or lateral movement. Manufactured homes must be anchored in accordance with state laws, local building codes, and FEMA guidelines. In the event that over-the-top frame ties to ground anchors are used, the following specific requirements (or their equivalent) shall be met:
(1) Over-the-top ties be provided at each of the four corners of the manufactured home with two additional ties per side at the intermediate locations and manufactured homes less than 50 feet long requiring one additional tie per side;
(2) Frame ties be provided at each corner of the home with five additional ties per side at intermediate points and manufactured homes less than 50 feet long requiring four additional ties per side;
(3) All components of the anchoring system be capable of carrying a force of 4,800 pounds; and
(4) Any additions to manufactured homes be similarly anchored.
(G) Assure that all manufactured homes that are placed or substantially improved within special flood hazard areas on the community’s official map on sites:
(1) Outside of a manufactured home park or subdivision;
(2) In a new manufactured home park or subdivision;
(3) In an expansion to an existing manufactured home park or subdivision; or
(4) In an existing manufactured home park or subdivision on which a manufactured home has incurred “substantial damage” as the result of a flood be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated at least one foot above the base flood elevation and be securely anchored to an adequately anchored foundation system in accordance with the provisions of division (F) above.
(H) Assure that manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within special flood hazard areas on the community’s official map that are not subject to the provisions of division (G) above be elevated so that either:
(1) The lowest floor of the manufactured home is at least one foot above the base flood elevation; or
(2) The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade and be securely anchored to an adequately anchored foundation system in accordance with the provisions of division (F) above.
(I) Require that recreational vehicles placed on sites within the identified special flood hazard areas on the community’s official map either be on the site for fewer than 180 consecutive days, be fully licensed and ready for highway use, or meet the permit requirements and the elevation and anchoring requirements for “manufactured homes” of this chapter. 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
(J) Structures used solely for agricultural purposes in connection with the production, harvesting, storage, drying, or raising of agricultural commodities, including the raising of livestock, may be constructed at-grade and wet flood-proofed; provided there is no human habitation or occupancy of the structure; the structure is of single-wall design; there is no permanent retail, wholesale, or manufacturing use included in the structure; a variance has been granted from the floodplain management requirements of this chapter; and a floodplain development permit has been issued.
(Prior Code, § 11-307) (Ord. 710, passed 11-17-2003)