The FP Overlay shall be subdivided into flood hazard zone areas as follows. Proposed development shall comply with the following requirements.
(a) 100-year Floodplain. The 100-year floodplain includes areas subject to a base flood (also called “100-year flood”) as defined by the Federal Flood Insurance Regulations. The following are the FEMA-designated flood hazard zones for this area: A, AE, AH, A1-30, and AO. (Note: FEMA-designated regulatory floodway is included within the AE zone.) The following standards shall apply to property within these zones:
(1) Elevation of First Floor. New construction and substantial improvement of any structure shall be constructed so that the first floor (including basement) shall be one foot or more above the base flood elevation, when the FEMA map base flood elevations are shown, and will not result in any significant increase in flood levels during a base flood discharge. When the base flood elevations are not shown, new construction and substantial improvement of any residential structure shall be constructed so that the first floor (including basement) shall be two feet or more above the natural pre-development highest adjacent grade.
(2) Review Procedures. A project proposed in this area shall be subject to a Floodplain Development Standards Review. These reviews shall ensure that the proposed project complies with this Development Code regarding flood protection measures and shall require the submittal of an elevation certificate completed by a licensed land surveyor, registered civil engineer, or architect who is authorized by State or local law to certify elevation information.
(3) Development Restriction. In areas where no regulatory floodway has been designated by FEMA, new construction, substantial improvement or other development (including fill) shall not be permitted within any areas designated by FEMA as A, A1-30, AO, AH, or AE on the FIRMs, 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 at any point within the community.
(4) FEMA-designated Floodways. Floodways, as defined by FEMA, are different from the Floodway Land Use Zoning District established in Chapter 82.01 (Land Use Plan, Land Use Zoning Districts, and Overlays) and regulated by Chapter 82.03 (Agricultural and Resource Management Land Use Zoning Districts) of this title. They are defined as the channels of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation. They are also referred to as “regulatory floodways” (see subsection 810.01.080(gg)(23)). They are generally coterminous with the County’s Floodway Land Use Zoning Districts. They are considered FEMA-designated flood hazard zones in that they are included within the AE zone.
(b) 100 to 500-year Floodplain. This area includes areas between limits of the base flood (100-year flood) and a 500-year flood; and certain areas subject to 100-year flooding with an average depth of less than one foot or where the contributing drainage areas are less than one square mile; or areas protected by levees from the base flood. The following are the FEMA-designated flood hazard zones for this area: A-99 and the shaded Zone X. The following standards shall apply to property within these zones:
(1) Elevation of First Floor. New construction and substantial improvement of any structure shall be so constructed that the first floor (including basement) shall be one foot above the natural pre-development highest adjacent grade.
(2) Review Procedures. A project proposed in this area shall be subject to a Floodplain Development Standards Review conducted by the Building and Safety Division based upon the determination by the Land Development Division of the Land Use Services Department. This review shall ensure that the proposed project complies with this Development Code regarding flood protection measures.
(c) Undetermined Flood Hazards. This area includes areas of undetermined, but possible, shallow flooding as determined by the County, the Flood Control District, or other governmental agency. The following standards shall apply to property within this area:
(1) Final Building Plan Content. The final building plans that are submitted for approval shall show the approved location and mitigating measures.
(2) Development Standards. Development standards for the undetermined flood hazard area shall be determined on a case-by-case and shall be dependent upon the specific of the project. A Floodplain Development Standards Review may be required.
(Ord. 4011, passed - -2007; Am. Ord. 4163, passed - -2012; Am. Ord. 4333, passed - -2017; Am. Ord. 4393, passed - -2020)