16.26.050   Structures—Construction restrictions.
   A.   Structures, residential and nonresidential, shall be constructed so as to offer the minimum obstruction to the flow of flood waters. Wherever possible, structures shall be constructed with the same alignment as the direction of flood flow; and so far as practicable, shall be placed approximately on the same alignment as those of adjoining structures.
   B.   All structures, residential and nonresidential, shall be firmly anchored to prevent flotation, collapse or lateral movement which might otherwise result in damage to other structures or restriction of bridge openings and other narrow sections of the watercourse. Anchoring for manufactured housing will be in conformance with state standards as established by the Office of Manufactured Housing under A.R.S. Title 41, Chapter 16, Article 2.
   C.   Service facilities such as electrical and heating equipment shall be constructed at or above the regulatory flood elevation for the particular area, or, in the case of nonresidential structures, be adequately flood proofed.
   D.   Any structure designed or utilized for human habitation, whether residential or nonresidential, that is used on a full-time or part-time basis shall have the lowest floor elevated at or above the regulatory flood elevation. Certification of elevation is required pursuant to Section 16.20.070.
   E.   Non-habitable, enclosed areas within the regulatory floodplain and below the regulatory flood elevation shall be designed in accordance with Section 16.26.030.E.
   F.   If fill is used to elevate any structure, the minimum elevation of the fill shall be at or above the base flood elevation, shall extend at such elevation for a distance of at least ten feet beyond the outside limit of the structure, and shall be adequately protected from erosion pursuant to Section 16.26.040.B unless a study or analysis prepared by an Arizona registered civil engineer demonstrates that a lesser distance or the absence of erosion protection is acceptable.
   G.   Structures, residential or nonresidential, designed or utilized for human habitation, whether on a full-time or part-time basis, and which will be completely surrounded by floodwaters during the base flood shall only be permitted when:
      1.   The product of the flow depth (d), in feet, times the square of the flow velocity (v), in feet per second, of the flood waters of the base flood does not exceed the numerical value of eighteen for a period in excess of thirty minutes at any point adjacent to the structure and associated improvements, including fill; and
      2.   The flood waters of the base flood do not exceed three feet in depth at any point adjacent to the structure and associated improvements, including fill;
      3.   For purposes of this section, depth and velocity shall be post development values and shall be calculated as follows:
         a.   When flow distribution information is available, it shall be used to provide the most representative values for flood depth and velocity;
         b.   When approximate information is available, average depths and velocities may be used.
(Ord. 2010-FC5 § 1 (part), 2010; Ord. 2005 FC-2 § 2 (part), 2005; 1998 FC-1 Section 2, 1998; Ord.1988 FC-2 Art. 9 (B) (2), 1988)