In addition to the requirements found in sections 13-1-6, 13-1-7 and 13-1-8 of this chapter for development in flood fringes, designated floodways, and SFHA or floodplains where no floodways have been identified (zones A, AO, AH, AE, A1-A30, A99, VO, V1-30, VE, V, M, E, D, or X), the following requirements shall be met:
(A) Public Health Standards:
1. No developments in the SFHA shall include locating or storing chemicals, explosives, buoyant materials, animal wastes, fertilizers, flammable liquids, pollutants, or other hazardous or toxic materials below the flood protection elevation (FPE).
2. New and replacement water supply systems, wells, sanitary sewer lines and on site waste disposal systems may be permitted providing all manholes or other aboveground openings located below the FPE are watertight.
(B) Carrying Capacity And Notification:
1. For all projects involving channel modification, fill, or stream maintenance (including levees), the flood carrying capacity of the watercourse shall be maintained.
2. In addition, the village shall notify adjacent communities in writing thirty (30) days prior to the issuance of a permit for the alteration or relocation of the watercourse.
(C) Protecting Buildings:
1. All buildings located within a 100-year floodplain also known as an SFHA, shall be protected from flood damage below the flood protection elevation. This building protection criteria applies to the following situations:
(a) Construction or placement of a new building;
(b) "Substantial improvement" to an existing building as defined in section 13-1-2 of this chapter;
(c) "Substantial damage" to an existing building as defined in section 13-1-2 of this chapter;
(d) Installing a manufactured home on a new site or a new manufactured home on an existing site. This building protection requirements does not apply to returning a mobile home to the same site it lawfully occupied before it was removed to avoid flood damage; and
(e) Installing a travel trailer on a site for more than one hundred eighty (180) days.
2. This building protection requirement may be met by one of the following methods. A residential or nonresidential building, when allowed, may be constructed on permanent land fill in accordance with the following:
(a) Lowest Floor: The lowest floor (including basement) shall be at or above the flood protection elevation.
(b) Fill Requirements:
(1) The fill shall be placed in layers no greater than one foot (1') deep before compaction and should extend at least ten feet (10') beyond the foundation of the building before sloping below the flood protection elevation.
(2) The top of the fill shall be above the flood protection elevation. However, the ten foot (10') minimum may be waived if a structural engineer certifies an alternative method to protect the building from damages due to hydrostatic pressures.
(3) The fill shall be protected against erosion and scour.
(4) The fill shall not adversely affect the flow or surface drainage from or onto neighboring properties.
3. A residential or nonresidential building may be elevated in accordance with the following:
(a) The building or improvements shall be elevated on crawl space, stilts, piles, walls, or other foundation that is permanently open to floodwaters and not subject to damage by hydrostatic pressures of the base flood or 100-year frequency flood. The permanent openings shall be no more than one foot (1') above existing grade, and consists of a minimum of two (2) openings. The openings must have a total net area of not less than one square inch for every one square foot of enclosed area subject to flooding below the base flood elevation.
(b) The foundation and supporting members shall be anchored and aligned in relation to flood flows and adjoining structures so as to minimize exposure to known hydrodynamic forces such as current, waves, ice and floating debris.
(c) All areas below the flood protection elevation shall be constructed of materials resistant to flood damage.
(1) The lowest floor (including basement) and all electrical, heating, ventilating, plumbing, and air conditioning equipment and utility meters shall be located at or above the flood protection elevation.
(2) Water and sewer pipes, electrical and telephone lines, submersible pumps, and other waterproofed service facilities may be located below the flood protection elevation.
(d) The areas below the flood protection elevation may only be used for the parking of vehicles, building access or storage in an area other than a basement.
(e) Manufactured homes, and travel trailers to be installed on a site for more than one hundred eighty (180) days, shall be elevated to or above the flood protection elevation; and, shall be anchored to resist flotation, collapse, or lateral movement by being tied down in accordance with the rules and regulations for the Illinois mobile home tie-down act issued pursuant to 77 Illinois administrative code part 870. In addition, all manufactured homes shall meet the following elevation requirements:
(1) In the case of manufactured homes placed or substantially improved: a) outside of a manufactured home park or subdivision, b) in a new manufactured home park or subdivision, c) in an expansion to an existing manufactured home park or subdivision, or d) in an existing manufactured home park or subdivision on which a manufactured home has incurred substantial damage from a flood, the top of the lowest floor shall be elevated to or above the flood protection elevation.
(2) In the case of manufactured homes placed or substantially improved in an existing manufactured home park or subdivision, the manufactured home shall be elevated so that either the top of the lowest floor is above the base flood elevation or the chassis is at least thirty six inches (36") in height above grade and supported by reinforced piers or other foundations of equivalent strength, whichever is less.
(f) Recreational vehicles or travel trailers shall be required to meet the elevation and anchoring requirements of subsection (C)3(e) of this section unless:
(1) They are on site for fewer than one hundred eighty (180) consecutive days; and
(2) They are fully licensed and ready for highway use. 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 utility and service devices, and has no permanently attached additions.
4. Only a nonresidential building may be structurally dry floodproofed (in lieu of elevation) provided that:
(a) A registered professional engineer shall certify that the building has been structurally dry floodproofed below the flood protection elevation, the structure and attendant utility facilities are watertight and capable of resisting the effects of the base flood or 100-year frequency flood.
(b) The building design shall take into account flood velocities, duration, rate of rise, hydrostatic and hydrodynamic forces, the effects of buoyancy, and impacts from debris or ice.
(c) Floodproofing measures shall be operable without human intervention and without an outside source of electricity (levees, berms, floodwalls and similar works are not considered floodproofing for the purpose of this subsection).
5. Existing buildings located within a designated floodway shall also meet the more restrictive appropriate use standards included in section 13-1-7 of this chapter. Nonconforming structures located in a designated floodway may remain in use and may only be enlarged, replaced or structurally altered in accordance with subsection 13-1-7(B) of this chapter. A nonconforming structure damaged by flood, fire, wind or other natural or manmade disaster may be restored unless the damage exceeds fifty percent (50%) of its market value before it was damaged, in which case it shall conform to this chapter. (Ord. 00-1075, 12-21-2000)
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