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b. Specific standards for above-grade, enclosed areas. Above-grade, fully enclosed areas such as <br />crawl spaces or tuck under garages must be designed to internally flood and the design plans <br />must stipulate: <br />1. A minimum area of openings in the walls where internal flooding is to be used as a flood <br />proofing technique. There shall be a minimum of two openings on at least two sides of the <br />structure and the bottom of all openings shall be no higher than one-foot above grade. The <br />automatic openings shall have a minimum net area of not less than one square inch for every <br />square foot subject to flooding unless a registered professional engineer or architect certifies <br />that a smaller net area would suffice. The automatic openings may be equipped with <br />screens, louvers, valves, or other coverings or devices provided that they permit the <br />automatic entry and exit of flood waters without any form of human intervention; and <br />2. That the enclosed area will be designed of flood resistant materials in accordance with the <br />FP-3 or FP-4 classifications in the State Building Code and shall be used solely for building <br />access, parking of vehicles or storage. <br />(2) Basements, as defined by section 78-1111 (a)(2) of this article, shall be subject to the following: <br />a. Residential basement construction shall not be allowed below the regulatory flood protection <br />elevation. <br />b. Non-residential basements may be allowed below the regulatory flood protection elevation <br />provided the basement is structurally dry flood proofed in accordance with section 78-1121 (3) of <br />this article. <br />(3) All areas of non residential structures including basements to be placed below the regulatory flood <br />protection elevation shall be flood proofed in accordance with the structurally dry flood proofing <br />classifications in the State Building Code. Structurally dry flood proofing must meet the FP-1 or FP-2 <br />flood proofing classification in the State Building Code and this shall require making the structure <br />watertight with the walls substantially impermeable to the passage of water and with structural <br />components having the capability of resisting hydrostatic and hydrodynamic loads and the effects of <br />buoyancy. Structures flood proofed to the FP-3 or FP-4 classification shall not be permitted. <br />( 4) When at any one time more than 1,000 cubic yards of fill or other similar material is located on a parcel <br />for such activities as on-site storage, landscaping, sand and gravel operations, landfills, roads, dredge <br />spoil disposal or construction of flood control works, an erosion/sedimentation control plan must be <br />submitted unless the community is enforcing a state approved shoreland management ordinance. In <br />the absence of a state approved shoreland ordinance, the plan must clearly specify methods to be <br />used to stabilize the fill on site for a flood event at a minimum of the 100-year or regional flood event. <br />The plan must be prepared and certified by a registered professional engineer or other qualified <br />individual acceptable to the city council. The plan may incorporate alternative procedures for removal <br />of the material from the flood plain if adequate flood warning time exists. <br />(5) Storage of materials and equipment. <br />a. The storage or processing of materials that are, in time of flooding, flammable, explosive, or <br />potentially injurious to human, animal, or plant life is prohibited. <br />b. Storage of other materials or equipment may be allowed if readily removable from the area within <br />the time available after a flood warning and in accordance with a plan approved by the city council. <br />(6) The provisions of section 78-1122 of this article shall also apply. <br />Sec. 78-1122. -Standards for all flood fringe uses. <br />(a) All new principal structures must have vehicular access at or above an elevation not more than two <br />feet below the regulatory flood protection elevation. If a variance to this requirement is granted, the <br />city council must specify limitations on the period of use or occupancy of the structure for times of <br />flooding and only after determining that adequate flood warning time and local flood emergency <br />response procedures exist. <br />Page 3