§ 15.40.070. Protecting buildings.

A.

In addition to the damage prevention requirements of Section 15.40.060 all buildings to be located in the SFHA shall be protected from flood damage below the FPE. This building protection requirement applies to the following situations:

1.

Construction or placement of a new building valued at more than one thousand dollars ($1,000.00);

2.

Structural alterations made to an existing building that increase the floor area by more than twenty (20) percent, or the market value of the building by more than fifty (50) percent;

3.

Reconstruction or repairs made to a damaged building that are valued at or more than fifty (50) percent of the market value of the building before the damage occurred;

4.

Installing a manufactured home on a new site or a new manufactured home on an existing site. This chapter does not apply to returning a manufactured home to the same site it lawful occupied before it was removed to avoid flood damage; and

5.

Installing a travel trailer on a site for more than one hundred eighty (180) days.

B.

The building protection requirement may be met by one (1) of the following methods. The building inspector shall maintain a record of compliance with these building protection standards as required in Section 15.40.030.

1.

A residential or nonresidential building may be constructed on permanent land fill in accordance with the following:

a.

The fill shall be placed in layers no greater than one (1) foot deep before compaction.

b.

The lowest floor (including basement) shall be at or above the FPE. The fill should extend at least ten (10) feet beyond the foundation of the building before sloping below the FPE.

c.

The fill shall be protected against erosion and scour during flooding by vegetative cover, rip rap, or bulkheading. If vegetative cover is used, the slopes shall be no steeper than three horizontal to one vertical (3:1).

d.

The fill shall not adversely affect the flow of surface drainage from or onto neighboring properties.

2.

A residential or nonresidential building may be elevated in accordance with the following:

a.

The building or improvements shall be elevated on crawl space, walls, stilts, piles or other foundation provided:

i.

The walls have permanent openings no more than one (1) foot above grade; and

ii.

The walls and floor are not subject to damage by hydrostatic pressures associated with the base flood.

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 forms such as current, waves, ice and floating debris.

c.

All areas below the FPE shall be constructed of materials resistant to flood damage. 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 FPE. Water and sewer pipes, electrical and telephone lines, submersible pumps, and other waterproofed service facilities may be located below the FPE.

3.

Manufactured homes and travel trailers to be installed on a site for more than one hundred eighty (180) days shall be:

a.

Elevated at or above the FPE in accordance with Subsection B.1 or 2 of this section; and

b.

Anchored to resist floatation, collapse or lateral movement by being tied down in accordance with the Rules and Regulations for the Illinois Mobile Home Tie-Down Act (210 ILCS 120/1 et seq.).

4.

Only a nonresidential building may be floodproofed in accordance with the following:

a.

A registered professional engineer shall certify that the building has been designed so that below the FPE, the structure and attendant utility facilities are watertight and capable of resisting the effects of the base flood. The building design shall take in to account flood velocities, duration, rate of rise, hydrostatic and hydrodynamic forces, the effects of buoyancy, and impacts from debris or ice.

b.

Floodproofing measures shall be operable without human intervention and without an outside source of electricity.

(Code 1996, § 15.40.070)