(A) (1) In addition to the damage prevention requirements of § 152.06, all buildings located in the floodplain shall be protected from flood damage below the flood protection elevation.
(2) This building protection requirement applies to the following situations:
(a) Construction or placement of a new building valued at low replacement value;
(b) Value of improvements equals or exceeds the market value by 50% during a ten-year period. If substantially improved, the existing structure and the addition must meet the flood protection standards of this section;
(c) Repairs made to a substantially damaged building. These repairs shall be figured cumulatively during a ten-year period. If substantially damaged, the entire structure must meet the flood protection standards of this section within 24 months of the date the damage occurred;
(d) Structures that are determined to be 50% and over are considered substantially damaged in the floodplain. The owner(s) shall have the right to appeal. An Appeals Board fee of $200 shall be paid by the appellant. Members of the Appeals Board shall be compensated as determined by the County Board. Refer to the county fee schedule in Chapter 36 of this code of ordinances. A written application for appeal must be received within 20 days after the notice of determination letter is received accompanied with the following documentation:
1. A contractor’s estimate to be completed by a licensed contractor listing all materials and cost of same to be replaced or added;
2. Hourly labor listed for each job using the county’s adopted wage scale; and
3. Inspection reports from a mechanical contractor and electrician certifying the electrical, HVAC, hot water heater or other mechanical equipment is working in a safe and efficient manner.
(e) Installing a manufactured home on a new site;
(f) Installing a travel trailer or recreational vehicle on a site for more than 180 days per year; and
(g) Repetitive loss to an existing building as defined in § 152.02.
(B) Residential or nonresidential buildings can meet the building protection requirements by one of the following methods:
(1) The building may be constructed on permanent landfill in flood fringe areas in accordance with the following:
(a) The lowest floor (including basement) shall be at or above the flood protection elevation;
(b) The fill shall be placed in layers no greater than six inches before compaction and should extend at least 20 feet beyond the foundation before sloping below the flood protection elevation;
(c) The fill shall be protected against erosion and scour during flooding by vegetative cover, riprap or other structural measures;
(d) The fill shall be composed of rock or soil and not incorporate debris or refuse materials; and
(e) The fill shall not adversely affect the flow of surface drainage from or onto neighboring properties and, when necessary, storm water management techniques such as swales or basins shall be incorporated.
(2) The building may be elevated in accordance with the following:
(a) The building or improvements shall be elevated on stilts, piles, walls or other foundation that is permanently open to flood waters;
(b) The lowest floor and all electrical, heating, ventilating, plumbing and air conditioning equipment and utility meters shall be located at or above the flood protection elevation;
(c) If walls are used, all enclosed areas below the flood protection elevation shall address hydrostatic pressures by allowing the automatic entry and exit of flood waters. Designs must either be certified by a registered professional engineer or architect and by having a minimum of one permanent opening on each wall no more than one foot above grade. The openings shall provide 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. Refer to FEMA TV 1, Openings in Foundation Walla and WALLS of Enclosures, for additional guidance;
(d) The foundation and supporting members shall be anchored, designed and certified so as to minimize exposure to hydrodynamic forces such as current, waves, ice and floating debris;
(e) The finished interior grade shall not be less than the finished exterior grade;
(f) All structural components below the flood protection elevation shall be constructed of materials resistant to flood damage;
(g) Water and sewer pipes, electrical and telephone lines, submersible pumps and other service facilities may be located below the flood protection elevation provided they are waterproofed; and
(h) The area below the flood protection elevation shall be used solely for parking or building access and not later modified or occupied as habitable space.
(3) Levees, berms, floodwalls and similar works are not considered floodproofing for the purpose of this section.
(C) Manufactured homes to be permanently installed on-site shall be:
(1) Elevated to or above the flood protection elevation; and
(2) 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 Ill. Admin. Code 870 et seq.;
(3) Porches or decks shall not be permanently attached;
(4) Electrical and mechanical elements shall be elevated above the BFE;
(5) All enclosures below the flood protection elevation shall address hydrostatic pressures by allowing automatic entry and exit of floodwaters, and shall be used for storage, parking or building access. Refer to FEMA TB 1, Openings in Foundation Walls and Walls of Enclosures, for additional guidance; and
(6) The vehicle must meet public health standards shall be met as referenced in § 152.09.
(D) Travel trailers and recreational vehicles on a site for more than 180 days shall meet the elevation requirements of division (C) above unless the following conditions are met:
(1) The vehicle must be either self-propelled or towable by a light duty truck. The hitch must remain on the vehicle at all times;
(2) The vehicle must not be attached to external structures such as decks and porches;
(3) The vehicle must be designed solely for recreation, camping, travel or seasonal use rather than as a permanent dwelling;
(4) The vehicles largest horizontal projections must be no larger than 400 square feet;
(5) The vehicle’s wheels must remain on axles and inflated;
(6) Air conditioning units must be attached to the frame so as to be safe for movement out of the floodplain;
(7) Propane tanks, electrical and sewage connections must be quick-disconnect and above the 100-year flood elevation;
(8) The vehicle must be licensed and titled as a recreational vehicle or park model; and
(9) The vehicle must be either:
(a) Entirely supported by jacks rather than blocks; or
(b) Have a hitch jack permanently mounted, have the tires touching the ground, and be supported by blocks in a manner that will allow the blocks to be easily removed by use of the hitch jack.
(10) The vehicle must be registered and permitted by the Floodplain Manager prior to being placed on site (includes RVs being returned to original site); and
(11) The vehicle must meet all of the requirements of § 152.09.
(E) (1) Nonresidential buildings may be structurally dry floodproofed (in lieu of elevation) provided a registered professional engineer or architect certifies that:
(a) Below the flood protection elevation the structure and attendant utility facilities are water-tight and capable of resisting the effects of the base flood;
(b) The building design accounts for flood velocities, duration, rate of rise, hydrostatic and hydrodynamic forces, the effects of buoyancy, and the impact from debris and ice; and
(c) Floodproofing measures will be incorporated into the building design and operable without human intervention and without an outside source of electricity.
(2) Levees, berms, floodwalls and similar works are not considered floodproofing for the purpose of this division (E).
(F) Minor accessory or shed structures constructed ancillary to a residential use may be permitted provided the following conditions are met:
(1) The structure or shed must be non-habitable;
(2) The structure or shed must be used only for the storage of vehicles and tools and cannot be modified later into another use;
(3) The structure or shed must be located outside of the floodway;
(4) The structure or shed must be on a single-family lot and be accessory to an existing principal structure on the same lot;
(5) Below the base flood elevation, the structure or shed must be built of materials not susceptible to flood damage;
(6) All utilities, plumbing, heating, air conditioning and electrical must be elevated above the flood protection elevation;
(7) The structure must have at least one permanent opening on each wall no more than one foot above grade with one square inch of opening for every square foot of floor area;
(8) The structure must be no more than one story in height and no more than 500 square feet in size;
(9) The structure shall be anchored to resist floatation and overturning;
(10) All flammable or toxic materials (gasoline, paint, insecticides, fertilizers and the like) shall be stored above the flood protection elevation; and
(11) The lowest floor elevation should be documented and the owner advised of the flood insurance implications.
(G) A building may be constructed with a crawlspace located below the flood protection elevation provided that the following conditions are met:
(1) The building must be designed and adequately anchored to resist flotation, collapse and lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy;
(2) Any enclosed area below the flood protection elevation shall have openings that equalize hydrostatic pressures by allowing for the automatic entry and exit of floodwaters. A minimum of one opening on each wall having a total net area of not less than one square inch per one square foot of enclosed area. The openings shall be no more than one foot above grade;
(3) The interior grade of the crawlspace below the flood protection elevation must not be more than two feet below the lowest adjacent exterior grade;
(4) The interior height of the crawlspace measured from the interior grade of the crawl to the top of the foundation wall must not exceed four feet at any point;
(5) An adequate drainage system must be installed to remove floodwaters from the interior area of the crawlspace within a reasonable period of time after a flood event;
(6) Portions of the building below the flood protection elevation must be constructed with materials resistant to flood damage; and
(7) Utility systems within the crawlspace must be elevated above the flood protection elevation.
(Ord. 21-4, passed 11-9-2021)