A. Review Application To Ensure Compliance: Building permit applications for development, location, demolition or alteration within delineated flood hazard areas, as shown on the flood insurance study for Caddo County and the town of Carnegie, dated September 27, 1991, with the accompanying flood insurance rate maps (FIRM) and flood boundary-floodway maps (FBFM), and any revision thereto, which are hereby adopted by reference, as if set out fully herein, shall be reviewed by the building inspector to ensure that all of the following requirements are met: (Ord. 188, 2-6-1992)
1. All building sites shall be reasonably safe from flooding. If a proposed building site is in a flood prone area, all new construction and substantial improvement (including the placement of prefabricated buildings and mobile homes) shall:
a. Be designed, modified and/or adequately anchored to prevent flotation, collapse or lateral movement of the structure. All manufactured housing to be placed within zone A on the community's flood hazard boundary map (FHBM) shall be anchored by providing over the top and frame ties to ground anchors. Over the top ties shall be provided at each of the four (4) corners of the mobile home, with two (2) additional ties per side at intermediate points, and manufactured homes less than fifty feet (50') long requiring one additional tie per side. Frame ties shall be provided at each corner of the home, with five (5) additional ties per side at intermediate points, and manufactured homes less than fifty feet (50') long requiring four (4) additional ties per side. All components of the anchoring system shall be capable of carrying a force of four thousand eight hundred (4,800) pounds. Any additions to the home shall be similarly anchored.
b. Be constructed with materials and utility equipment resistant to flood damage.
c. Be constructed by methods and practices that minimize flood damages.
d. Be constructed with electrical, heating, plumbing, ventilation and air conditioning equipment and other service facilities that are designed and/or located to prevent water from entering or accumulating within the components during conditions of flooding.
2. All new and replacement water supply systems within flood prone areas shall be designed to minimize or eliminate infiltration of floodwaters into the systems.
3. All new and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharges from the systems into floodwaters.
4. On site waste disposal systems within flood prone areas shall be located to avoid impairment to them, or contamination from them, during flooding.
5. The building inspector shall utilize all available 100-year flood elevation data to review building permit applications, and shall require that all applications for development within a flood prone area be accompanied by: a) the elevation of the lowest habitable floor (including basement) of all new or substantially improved structures; and b) a certificate signed by a registered professional engineer or architect, stating that the floodproofing methods to be utilized are adequate to withstand the flood depths, pressures, velocities, impact and uplift forces, and other factors associated with the 100-year flood, and indicating the specific elevation to which the structure will be floodproofed. New construction and substantial improvements, with fully enclosed areas below the lowest floor that are subject to flooding, shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect, or meet or exceed the following minimum criteria:
a. A minimum of two (2) openings having a total net area of not less than one square inch for every one square foot of enclosed area subject to flooding shall be provided;
b. The bottom of all openings shall be no higher than one foot (1') above grade; and
c. Openings may be equipped with screens, louvers, valves or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters.
6. All new construction or substantial improvement of residential structures within zones A1-30 on the town's flood insurance rate map (FIRM) shall have the lowest floor, including basement, elevated one foot (1') above the level of the 100-year flood.
7. Within zones A1-30 on the town's flood insurance rate map (FIRM), all manufactured housing not in a park or subdivision, all new manufactured housing parks and subdivisions, all expansions to existing manufactured housing parks and subdivisions, and all repairs, reconstruction or improvement of streets, utilities and/or pads in existing manufactured housing parks or subdivisions, shall be located, developed, expanded or improved according to the following criteria:
a. All manufactured housing shall be placed, or be capable of being placed, on compacted fill or on pilings, so that the lowest floor of the home will be one foot (1') above the level of the 100-year flood;
b. All lots shall have adequate provisions for surface drainage and access; and
c. All manufactured housing to be elevated on pilings shall: 1) be placed on lots large enough to permit steps; 2) provide for piling foundations to be placed in stable or stabilized soils, no more than ten feet (10') apart; and 3) provide for reinforcement of piers more than six feet (6') above ground level.
8. All new construction or substantial improvement of residential structures located within any AO (area of shallow flooding) zone, as shown on the town's flood insurance rate map (FIRM), shall have the lowest floor, including basement, elevated above the highest adjacent grade or the crown of the nearest street, one foot (1') above the depth number specified for the area on the town's flood insurance rate map (FIRM). Within zone AH or AO, adequate drainage paths around structures on slopes shall be required.
9. All new construction or substantial improvement of nonresidential structures within zones A1-30 on the town's flood insurance rate map (FIRM) shall:
a. Have the lowest floor, including basement, elevated one foot (1') above the level of the 100-year flood; or
b. Be designed, together with attendant utility and sanitary facilities, so that, below the level of the 100-year flood, the structure is watertight, with walls substantially impermeable to the passage of water, and contain structural components capable of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy.
10. All new construction or substantial improvement of nonresidential structures within any AO (area of shallow flooding) zone on the town's flood insurance rate map (FIRM) shall:
a. Have the lowest floor, including basement, elevated above the highest adjacent grade or the crown of the nearest street, one foot (1') above the depth number specified on the town's flood insurance rate map (FIRM); or
b. Be completely floodproofed, along with attendant utility and sanitary facilities, to one foot (1') above the depth number specified on the town's flood insurance rate map (FIRM), so that any space below the level is watertight, with walls substantially impermeable to the passage of water, and contain structural components capable of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy; and
c. Be required to include, within zones AH or AO, adequate drainage paths around structures on slopes, to guide floodwaters around and away from proposed structures.
11. The requirements of this chapter shall also be in effect for building permit applications for development located within any A99 zones on the town's flood insurance rate map (FIRM).
12. Floodways, as designated on the town's official flood hazard boundary map (FHBM), are hazardous areas due to: a) the velocity of floodwaters which carry debris and potentially damaging projectiles; and b) the creation of severe erosion problems. The following provisions apply within designated floodway areas:
a. Encroachments are prohibited, including fill, new construction, substantial improvements and other developments, unless certification by a professional registered engineer or architect is provided, demonstrating that encroachments shall not result in any increase in flood levels during occurrence of the base flood discharge.
b. If the provisions of subsection A12a of this section are satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this code.
B. Additional Responsibilities Of Building Inspector: The building inspector shall have the following additional responsibilities in the review of building permit applications for development, location, demolition or alteration within a delineated flood hazard area.
1. Building permit applications shall be reviewed to ensure that all necessary governmental agency permits required by state or federal law have been obtained.
2. In the case of building permit applications for alteration or relocation of a watercourse, the building inspector shall:
a. Notify adjacent communities and the state flood insurance coordinating office prior to such work (and submit copies of such notification to the federal flood insurance administrator); and
b. Obtain written assurances from the building permit applicant that the flood carrying capacity within the altered or relocated portion of the watercourse will be maintained.
3. For the purpose of determining future flood insurance risk premium rates, the building inspector shall maintain records of:
a. The elevation of the lowest habitable floor of all new or substantially improved structures; and
b. Floodproofing certificates (including the specific elevation to which the structures are floodproofed).
4. When a regulatory floodway has not been designated, the building inspector must require that no new construction, substantial improvements, or other development (including fill) shall be permitted within zones A1-30 and AE on the community's FIRM, unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the water surface elevation of the base flood more than one foot (1') at any point within the community.
5. The building inspector shall utilize the full range of the community's floodplain management regulations in this review.
C. Permit Issuance; Nonliability Of Town Officials: Issuance of a building permit for development within an identified flood hazard area shall not create liability on the part of any town official for any flood damages resulting from reliance upon the provisions of this section, or any administrative decision lawfully made hereunder. (1992 Code § 4-10)
Notes
| 1 | 1. See also chapter 5 of this title. |