Skip to code content (skip section selection)
In all areas of special flood hazards the following standards are required:
.011 All new construction and substantial improvement shall (i) be designed (or modified) and adequately anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy, (ii) be constructed with materials resistant to flood damage, (iii) be constructed by methods and practices that minimize flood damages, and (iv) be constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
.020 Construction materials and methods.
.022 All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
.030 Elevation and floodproofing.
.031 New construction and substantial improvement of any structure shall have the lowest floor, including basement, elevated at least one foot above the base flood elevation. Nonresidential structures may meet the standards in Section 17.28.130.022. Prior to final building and zoning inspections, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor and an elevation certificate completed and provided to the Planning Director, or his or her designee.
.032 New construction and substantial improvement of any structure in zone AO shall have the lowest floor, including basement, elevated above the highest adjacent grade to a height exceeding the depth number specified in feet on the FIRM plus one foot, or at least three feet above the highest adjacent grade if no depth number is specified. Nonresidential structures may meet the standards in Section 17.28.130.030.033. Upon completion of the structure, a registered professional engineer shall certify that the elevation of the structure meets this standard and provide the certification to the Planning Director, or designee.
.033 Nonresidential construction shall either be elevated in conformance with Section 17.28.130.030.031 or 17.28.130.030.032 or together with attendant utility and sanitary facilities:
(a) Be floodproofed so that below the base flood level the structure is watertight with walls substantially impermeable to the passage of water;
(b) Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and
(c) Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certification shall be provided to the Planning Director, or designee.
.034 Mobile homes shall meet the above standards and also the standards in Section 17.28.170.
.035 All 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 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 flood waters. Designs for meeting this requirement must be certified by a registered professional engineer within the State of California or meet or exceed the following minimum criteria:
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. The bottom of all openings shall be no higher than one foot above grade. Openings may be equipped with screens, louvers or valves.
.036 Within Zones AH and AO, adequate drainage paths shall be constructed around structures on slopes to guide flood waters around and away from proposed structures. (Ord. 4138 § 1 (part); June 30, 1980: Ord. 4879 §§ 12, 13, 14, 20 (part); December 1, 1987: Ord. 4963 § 4, September 27, 1988: Ord. 5217 § 6; May 7, 1991: Ord. 5547 § 10; December 19, 1995: Ord. 5681 § 7; May 11, 1999: Ord. 6512 § 13; August 24, 2021.)