Section 8-624 Shallow Flooding Area Requirements
Located within the official FIRM map are areas designated as areas of shallow flooding. These areas have special flood hazards associated with base flood depths of more than one foot (1') to three feet (3') where a clearly defined channel does not exist and where the path of flooding is unpredictable and intermediate. In areas of shallow flooding the following provisions shall apply:
8-624.A. Residential Structures. All new construction and substantial improvements of residential structures shall have the lowest floor (including basement) electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), elevated to one 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.
8-624.A.1. Within any AO or AH Zone on the FIRM, all new construction and substantial improvements of residential structures shall have the lowest floor (including basement and attendant utilities) elevated above the highest adjacent grade at least one foot above the depth number specified in feet on the FIRM, or at least three feet (3') if no depth number is specified.
8-624.A.2. Within Zones AO of AH adequate drainage paths around structures on slopes shall be provided to guide flood waters around and away from proposed structures.
8-624.B. Non-Residential Structures. With the exception of Critical Facilities new construction and substantial improvements of any commercial, industrial or other non residential 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 one foot above base flood elevation, or together with attendant utility and sanitary facilities, shall, be designed so that at one 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, specification, 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.
8-624.B.1. Within any AO or AH Zone on the FIRM, all new construction and substantial improvements of nonresidential structures shall have the lowest floor (including basement and utilities) elevated above the highest adjacent grade at least one foot above the depth number specified in feet on the FIRM, or at least three feet (3') if no depth number is specified together with attendant utility and sanitary facilities shall be completely floodproofed to that level
8-624.B.2. Within any AO or AH Zone on the FIRM, adequate drainage paths around structures on slopes shall be provided to guide flood waters around and away from proposed structures.
8-624.C. Openings Below the Lowest Floor. For all new construction and substantial improvements, fully enclosed areas below the lowest floor that are usable solely for parking of vehicles, building access, or storage in any area other than a basement which 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 must meet or exceed the following minimum criteria:
8-624.C.1. A minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided.
8-624.C.2. The bottom of all openings shall be no higher than one foot above grade.
8-624.C.3. Openings may be equipped with screens, valves, louvers, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.