Located within the areas of special flood hazard established in § 150.07, are areas designated as coastal high hazard areas in/along Lake Michigan (Zone VE). These areas have special flood hazards associated with wave wash. The following provisions apply within coastal high hazard areas:
(A) Human-made alterations of sand dunes within a coastal high hazard area are prohibited unless an engineering report documents that the alterations will not increase potential flood damage by reducing the wave and flow dissipation characteristics of the sand dunes.
(B) The use of fill for structural support of buildings is prohibited.
(C) Non-structural fill within a coastal high hazard area shall be permitted only if an engineering report demonstrates that the fill will not cause runup, ramping, or deflection of floodwaters that cause damage to buildings.
(D) Within a Coast High Hazard Area, bulkheads, seawalls, revetments, and other erosion control measures shall not be connected to the foundation or superstructure of a building and shall be designed and constructed so as not to direct floodwaters or increase flood forces or erosion impacts on the foundation or superstructure of any building.
(E) New construction and substantial improvements must be elevated on pilings or columns so that the bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is at or above the FPG. The pile or column foundation and structure attached thereto must be anchored to resist flotation, collapse, and lateral movement due to the effects of wind and water loads acting simultaneously on all building components.
(1) Water loading values used must be those associated with the base flood.
(2) Wind loading values used must be those required by applicable state or local building standards; or in the absence of applicable state or local building standards, those determined according to American Society of Civil Engineers 7-16, Minimum design loads and associated criteria for buildings and other structures, or equivalent standard.
(3) A registered professional engineer or architect must develop or review the structural design, specifications, and plans for the construction, and must certify that the design and methods of construction to be used are in accordance with accepted standards of practice for meeting the provisions of this section.
(4) New construction and substantial improvements must have the space below the lowest floor either free of obstruction or be constructed with non-supporting breakaway walls, open wood latticework, or insect screening intended to collapse under wind and water loads without causing collapse, displacement, or other structural damage to the elevated portion of the building or supporting foundation system.
(5) For purposes of this section, a breakaway wall must have a design safe loading resistance of not less than ten and no more than 20 pounds per square foot.
(6) Use of breakaway walls that exceed a design safe loading resistance of 20 pounds per square foot, either by design or where so required by local or State codes) may be permitted only if a registered professional engineer or architect certifies that the design proposed meets the following conditions:
(a) Breakaway wall collapse must result from a water load less than that which would occur during the base flood; and
(b) The elevated portion of the building and supporting foundation system must not be subject to collapse, displacement, or other structural damage due to the effects of wind and water loads acting simultaneously on all building components, structural and nonstructural.
1. Water loading values used must be those associated with the base flood.
2. Wind loading values used must be those required by applicable State or local building standards; or in the absence of applicable State or local building standards, those determined according to American Society of Civil Engineers 7-16, Minimum design loads and associated criteria for buildings and other structures, or equivalent standard.
(7) Any enclosed space below the lowest floor shall be used solely for parking of vehicles, building access, or storage.
(8) Placement or substantial improvement of manufactured homes must comply with § 150.047(D).
(9) Recreational vehicles must either:
(a) Be on site for fewer than 180 consecutive days;
(b) Be fully licensed and ready for highway use; or
(c) Comply with § 150.047(D).
(Ord. 2022-09, passed 9-20-2022)