As used in this chapter:
DESIGN FLOOD: The selected flood against which protection is provided, or eventually will be provided, by means of flood protective or control works. When a federal survey has been authorized, the design flood will be determined by the appropriate federal agency, and in all other cases it will be determined by the San Bernardino County flood control district. It is the basis for design and operation of a particular project after full consideration of flood characteristics, frequencies and potentials, and economic and other practical considerations.
FLOOD: Any temporary rise in stream flow or water surface level that results in significant adverse effects in the floodplain. "Adverse effects of floods" may include damages from overflow of land areas, effects of temporary backwater on sewers and local drainage channels, bank erosion or channel shifts, unsanitary conditions, or other unfavorable conditions resulting from deposition of materials in stream channels during flood recessions, rise of ground water coincident with increased stream flow, and interruption of traffic at bridge crossings.
FLOODPLAIN: The relatively flat area or lowlands adjoining the channel of a stream or watercourse, and subject to overflow by floodwaters.
FLOODPLAIN ZONING: The floodplain of the design flood shall be divided into two (2) zones for regulation purposes:
A. Zone FP-1, Designated Floodway: The channel of a stream and that portion of the adjoining floodplain required to reasonably provide for the construction of a project for passage of the design flood, including the lands necessary for construction of project levees;
B. Zone FP-2, Restrictive Zone: The portion of the natural floodway between the limits of the designated floodway and the limits of the floodplain, as determined by the selected flood, where inundation may occur but where depths and velocities are generally low. (Ord. 1000 § 31.62, 1955)