10-3-20: SPECIFIC STANDARDS FOR FLOOD HAZARD REDUCTION:
In all special flood hazard areas where base flood elevation data has been provided as set forth in: (A) section 10-3-8 of this chapter, (B) subsection 10-3-16(G) of this chapter, or (C) section 10-3-25 of this chapter, the following provisions are required:
A. Residential Construction: New construction and substantial improvement of any residential structure shall have the lowest floor (including basement), electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), elevated to 1 foot above the base flood elevation. Upon completion of the structure, the elevation of the lowest floor, including basement, shall be certified by a registered Colorado professional engineer, architect, or land surveyor. Such certification shall be submitted to the floodplain administrator.
B. Nonresidential Construction: With the exception of critical facilities, outlined in section 10-3-26 of this chapter, new construction and substantial improvements of any commercial, industrial, or other nonresidential structure shall either have the lowest floor (including basement), electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), elevated to 1 foot above the base flood elevation or, together with attendant utility and sanitary facilities, be designed so that at 1 foot above the base flood elevation the structure is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.
A registered Colorado professional engineer or architect shall develop and/or review structural design, specifications, and plans for the construction, and shall certify that the design and methods of construction are in accordance with accepted standards of practice as outlined in this subsection. Such certification shall be maintained by the floodplain administrator, as required by section 10-3-17 of this chapter.
C. Enclosures: New construction and substantial improvements, with fully enclosed areas below the lowest floor that are usable solely for parking of vehicles, building access, or storage in an area other than a basement and 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 Colorado professional engineer or architect or meet or exceed the following minimum criteria:
1. A minimum of two (2) openings having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding shall be provided;
2. The bottom of all openings shall be no higher than 1 foot above grade; and
3. Openings may be equipped with screens, louvers, valves, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters.
D. Manufactured Homes: All manufactured homes that are placed or substantially improved within Zones A1-30, AH, and AE on the town's FIRM on sites: (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 manufactured home has incurred "substantial damage" as a result of a flood, shall be elevated on a permanent foundation such that the lowest floor of the manufactured home, electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), are elevated to 1 foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
All manufactured homes shall be placed or substantially improved on sites in an existing manufactured home park or subdivision within Zones A1-30, AH and AE on the town's FIRM that are not subject to the provisions of the above section shall be elevated so that either:
1. The lowest floor of the manufactured home, electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), are 1 foot above the base flood elevation; or
2. The manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than 36 inches in height above grade and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
E. Recreational Vehicles: All recreational vehicles placed on sites within Zones A1-30, AH, and AE on the town's FIRM either:
1. Be on the site for fewer than one hundred eighty (180) consecutive days;
2. Be fully licensed and ready for highway use; or
3. Meet the permit requirements of section 10-3-17 of this chapter, and the elevation and anchoring requirements for "manufactured homes" in subsection D of this section.
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 utilities and security devices, and has no permanently attached additions.
F. Prior Approved Activities: Any activity for which a floodplain development permit was issued by the town or a CLOMR was issued by FEMA prior to the effective date of this chapter may be completed according to the standards in place at the time of the permit or CLOMR issuance, and will not be considered in violation of this chapter if it meets such standards. (Ord. 3, Series 2022)