(a) Scope. This section does not apply to piers or structures for the wet storage of watercraft if the piers or storage structures do not contain habitable space.
(b) Generally. Development may not occur in the floodplain if an alternative location for the development exists. All development shall be consistent with applicable flood hazard and watershed management plans and shall be undertaken in a manner that minimizes adverse impact on aquatic or terrestrial habitats and related flora and fauna. Grading, necessary provisions for drainage, erosion, and sediment control, and vegetative establishments may not increase flooding. Structures shall be constructed and placed on the lot so as to offer the minimum obstruction to the flow and height of floodwater. Materials that are hazardous, buoyant, flammable, or explosive, or that in times of flooding could be injurious to human, animal, or plant life, are prohibited below the flood protection elevation. Basements are prohibited. Reconstruction, rehabilitation, or restoration of a historic structure may not cause an increase in the elevation of the 100-year flood level. If a proposed building, structure or substantial improvement is sited in two different subdistricts or in a subdistrict with two different 100-year elevations, the more restrictive regulations or the higher flood elevation shall prevail.
(c) Elevation to flood protection elevation; exceptions. All structures, new construction, substantial improvements, and new habitable space shall have the lowest floor elevated to the flood protection elevation, except that:
(1) an expansion that increases the footprint of a structure is not required to have the lowest floor elevated to the flood protection elevation if the expansion is the minimum necessary to correct violations of State or County health, safety, or sanitary codes;
(2) an accessory structure or attached garage is not required to have the enclosed area below the lowest floor elevated to the flood protection elevation if the provisions of this section and § 16-2-203 are met; and
(3) new construction of or substantial improvements to nonresidential structures may be floodproofed in lieu of having the lowest floor elevated to the flood protection elevation if:
(i) the floodproofing designs ensure that areas below the flood protection elevation are watertight with walls substantially impermeable to the passage of water and with structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy for flooding to the flood protection elevation; and
(ii) a FEMA floodproofing certificate is provided.
(d) Water equalizing vents. New construction of or substantial improvements to a lowest floor or enclosed area below the lowest floor that is not required under this section to be elevated to the flood protection elevation shall be constructed with water equalizing vents in accordance with the requirements of the Building Code adopted by Article 15, Title 2, of this Code.
(e) Electrical, plumbing, and mechanical systems; utilities. Electrical, plumbing, and mechanical systems shall be installed in accordance with § 15-2-101 of this Code for commercial structures and § 15-2-102 of this Code for residential structures. New or replacement water and sewer connections shall be designed and floodproofed to eliminate or minimize the potential for flood damage, including infiltration of floodwater into the connections and discharges from the connections into floodwater. Onsite waste disposal connections shall be located to avoid impairment to them or contamination from them during flooding. Gas, electrical, and other facility and utility connections shall be located, constructed, and floodproofed to eliminate or minimize potential for flood damage. New storm drainage facilities within or leading to or from a floodplain shall be adequately designed, floodproofed, and installed to eliminate or minimize potential for property damage from the floodwaters of the 100-year flood and to minimize adverse environmental impact of their installation and use.
(f) Coastal high hazard areas. Manufactured homes and the placement of fill are prohibited in coastal high hazard areas. New construction of or a substantial improvement to a structure in a coastal high hazard area is prohibited unless the construction or improvement is in accordance with the Federal Emergency Management Agency's Coastal Construction Manual (FEMA 55), Manufactured Home Installation in Flood Hazard Areas (FEMA 85), Flood Resistant Design and Construction (ASCE 24-05) and NFIP Technical Bulletin 5 and 9.
(g) Floodways. All residential development, manufactured homes and the placement of fill are prohibited in a floodway. New construction of or a substantial improvement to a structure in a floodway is prohibited unless hydrologic and hydraulic analyses based on floodway models and performed in accordance with standard engineering practices demonstrate that the construction or improvement will not cause an increase in downstream or upstream flooding or erosion. Structures and fences, except two-wire fences, that impede, retard, or change the direction of the flow of water, that catch or collect debris carried by water, or that are placed where the natural flow of the stream or floodwaters will carry debris downstream are prohibited.
(Bill No. 58-10)