(a) General Standards. In all areas of special flood hazard 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 resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.
B. All manufactured homes, not otherwise regulated by the Ohio Revised Code pertaining to manufactured home parks, shall be anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy. Methods of anchoring may include, but are not limited to, use of over-the-top or frame ties to ground anchors.
(2) Construction materials and methods.
A. All new construction and substantial improvements shall be constructed with materials resistant to flood damage;
B. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage; and
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.
(3) Utilities. The following standards apply to all water supply, sanitary sewerage and waste disposal systems not otherwise regulated by the Ohio Revised Code:
A. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the systems;
B. New and replacement sanitary sewerage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharge from the systems into flood waters; and,
C. On site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.
(4) Subdivision Proposals.
A. All subdivision proposals, including manufactured home subdivisions, shall be consistent with the need to minimize flood damage;
B. All subdivision proposals, including manufactured home subdivisions, shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize flood damage;
C. All subdivision proposals, including manufactured home subdivisions, shall have adequate drainage provided to reduce exposure to flood damage; and
D. All subdivision proposals, including manufactured home subdivisions, shall meet the specific standards of subsection (b)(6), Subdivisions and Large Developments.
(5) Standards in areas of special flood hazard without base flood elevation data. In all areas of special flood hazard identified as Zone A on the Flood Insurance Rate Map where base flood elevation data are not available from any source, the following provisions apply:
New construction and substantial improvement of any residential, commercial, industrial, or other nonresidential structure shall have the lowest floor, including basement, elevated to at least two feet above the highest adjacent natural grade.
(b) Specific Standards. In all areas of special flood hazard where base flood elevation data have been provided as set forth in Section 1315.03(b), Basis for Establishing the Areas of Special Flood Hazard; Section 1315.04(d)(2), Use of Other Base Flood Elevation and Floodway Data; or subsection (b)(6) hereof, Subdivisions and Large Developments, the following provisions are required:
(1) Residential construction. New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated to the base flood elevation.
(2) Nonresidential construction. New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated to the level of the base flood elevation; or, together with attendant utility and sanitary facilities, shall:
A. Be floodproofed so that the structure is watertight with walls substantially impermeable to the passage of water to the level of the base flood elevation. In order to be eligible for lower flood insurance rates, the structure should be floodproofed at least one foot above the base flood elevation.
B. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and,
C. Be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with accepted standards of practice for meeting the standards of this subsection. Such certification shall be provided to the official as set forth in Section 1315.04(a)(3).
(3) Accessory structures. A relief to the elevation or dry floodproofing standards may be granted for accessory structures (e.g., sheds, detached garages) containing 576 square feet or less in gross floor area. Such structures must meet the encroachment provisions of subsection (c)(1)A. hereof and the following additional standards:
A. They shall not be used for human habitation;
B. They shall be designed to have low flood damage potential;
C. They shall be constructed and placed on the building site so as to offer the minimum resistance to the flow of flood waters;
D. They shall be firmly anchored to prevent flotation; and,
E. Service facilities such as electrical and heating equipment shall be elevated or floodproofed.
(4) Manufactured homes and recreational vehicles.
A. The following standards shall apply to all new and substantially improved manufactured homes not subject to the manufactured home requirements of Section 3733.01, Ohio Revised Code:
1. Manufactured homes shall be anchored in accordance with subsection (a)(1)B. hereof.
2. Manufactured homes shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is at the base flood elevation.
B. These standards also apply to recreational vehicles that are either:
1. Located on sites for 180 days or more, or
2. Are not fully licensed and ready for highway use.
(5) Enclosures below the lowest floor. The following standards apply to all new and substantially improved residential and nonresidential structures which are elevated to the base flood elevation using pilings, columns, or posts. 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:
A. Be certified by a registered professional engineer or architect; or,
B. Must meet or exceed the following criteria:
1. 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.
2. The bottom of all openings shall be no higher than one foot above grade. Openings may be equipped with screens, louvers, valves, or other openings provided that they permit the automatic entry and exit of floodwaters.
(6) Subdivisions and large developments. In all areas of special flood hazard where base flood elevation data have not been provided in accordance with Section 1315.03(b), Basis for Establishing the Areas of Special Flood Hazard, or Section 1315.04(d)(2), Use of Other Base Flood Elevation Data, the following standards apply to all subdivision proposals, including manufactured home subdivisions, and other proposed developments containing at least 50 lots or 5 acres (whichever is less):
A. The applicant shall provide base flood elevation data performed in accordance with standard engineering practices;
B. If subsection (b)(6)A. hereof is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of subsection (a), General Standards, and subsection (b), Specific Standards.
(c) Floodways.
(1) Areas with floodways. The Flood Insurance Study referenced in Section 1315.03(b) identifies a segment within areas of special flood hazard known as a floodway. Floodways may also be delineated in other sources of flood information as specified in Section 1315.04(d)(2). The floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles, and erosion potential. The following provisions apply within all delineated floodway areas:
A. Prohibit encroachments, including fill, new construction, substantial improvements, and other development unless a hydrologic and hydraulic analysis performed in accordance with standard engineering practices demonstrates that the proposed encroachment would not result in any increase in flood levels during the occurrence of the base flood discharge.
B. If subsection (c)(1)A. hereof is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of subsection (b), Specific Standards.
C. Any encroachment within the floodway that would result in an increase in base flood elevations can only be granted upon the prior approval by the Federal Emergency Management Agency. Such request must be submitted by the Building Officer to the Federal Emergency Management Agency and must meet the requirements of the National Flood Insurance Program.
(2) Areas without floodways. In all areas of special flood hazard where FEMA has provided base flood elevation data as set forth in Section 1315.03(b), but FEMA has not delineated a floodway, the following provisions apply:
A. New construction, substantial improvements, or other development (including fill) shall only be permitted if it is demonstrated that the cumulative effect of any proposed development, when combined with all other existing and anticipated development, shall not increase the water surface elevation of the base flood more than one (1) foot at any point.
B. If subsection (c)(2)A. hereof is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of Section 1315.05, Provisions for Flood Hazard Reduction. (Ord. 1998-139. Passed 9-28-98.)