In addition to the requirements found in sections 13-2-6, 13-2-7 and 13-2-8 of this chapter for development in flood fringes, regulatory floodways, and SFHAs or floodplains where no floodways have been identified (zones A, AO, AR, AE, A99, AH, VE, V, X or D), the following requirements shall be met: (Prior ord.; amd. 2011 Code)
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 FPE.
2. New and replacement water supply systems, wells, sanitary sewer lines and on site waste disposal systems may be permitted, provided all manholes or other aboveground openings located below the FPE are watertight.
B. Carrying Capacity And Notification: For all projects involving channel modification, fill or stream maintenance (including levees), the flood carrying capacity of the watercourse shall be maintained. 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. However, existing buildings located within a regulatory floodway shall also meet the more restrictive appropriate use standards included in section 13-2-7 of this chapter. This building protection criteria applies to the following situations:
a. Construction or placement of a new building;
b. Nonconforming structures may remain in use, but shall not be enlarged, replaced or structurally altered. A nonconforming structure damaged by flood, fire, wind or other manmade or natural disaster may be restored unless the damage exceeds fifty percent (50%) of its market value, in which case, it must, thereafter, conform to this chapter;
c. Installing a manufactured home on a new site or a new manufactured home on an existing site. This building protection requirement does not apply to returning a mobile home to the same site it lawfully occupied before it was removed to avoid flood damage; and
d. 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. Construction On Permanent Landfill: A residential or nonresidential building, when allowed, may be constructed on permanent landfill in accordance with the following:
(1) The lowest floor (including basement) shall be a minimum of three feet (3') above the flood protection elevation.
(2) 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. 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. The fill shall be protected against erosion and scour. The fill shall not adversely affect the flow or surface drainage from or onto neighboring properties.
b. Elevation Of Buildings: A residential or nonresidential building may be elevated in accordance with the following:
(1) 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 grade and consist 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.
(2) 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. (Prior ord.)
(3) All areas below the flood protection elevation shall be constructed of materials resistant to flood damage. The lowest floor (including basement) and all electrical, heating (including ductwork), ventilating, plumbing, and air conditioning equipment and utility meters shall be located at or above the flood protection elevation. Water and sewer pipes, electrical and telephone lines, submersible pumps, and other waterproofed service facilities may be located below the flood protection elevation. (Ord. 2004-49, 6-17-2004)
(4) No area below the flood protection elevation shall be used for storage of items or materials.
(5) 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 1 issued pursuant to 77 Illinois administrative code 870.
c. Dry Floodproofing Of Nonresidential Buildings: Only a nonresidential building may be structurally dry floodproofed (in lieu of elevation); provided, that 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. 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. 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.)
d. Toolsheds And Detached Garages: Toolsheds and detached garages on an existing single-family platted lot may be constructed with the lowest floor below the flood protection elevation in accordance with the following:
(1) The building is not used for human habitation.
(2) All areas below the base flood or 100-year frequency flood elevation shall be constructed with waterproof material. Structures located in a regulatory floodway shall be constructed and placed on a building site so as not to block the flow of floodwaters and shall also meet the appropriate use criteria of section 13-2-7 of this chapter. In addition, all other requirements of sections 13-2-6, 13-2-7 and 13-2-8 of this chapter must be met.
(3) The structure shall be anchored to prevent flotation.
(4) Service facilities such as electrical and heating equipment shall be elevated or floodproofed to the flood protection elevation.
(5) The building shall be valued at less than five thousand dollars ($5,000.00) and be less than five hundred (500) square feet in floor size.
(6) The building shall be used only for the storage of vehicles or tools and may not contain other rooms, workshops, greenhouses or similar uses.
e. Nonconforming Structures: Nonconforming structures located in a regulatory floodway may remain in use but may not be enlarged, replaced or structurally altered. 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. (Prior ord.)
Notes
| 1 | 1. 210 ILCS 120/1 et seq. |