Tustin, CA Environmental Rules: Flood Zones (2026)

Tustin City Code Chapter 8 of Article 9 applies to all special flood hazard areas within the City as identified on the Federal Insurance Administration's Flood Insurance Study and accompanying Flood Insurance Rate Maps dated January 3, 1997, and all later amendments, which Section 9802.1a adopts by reference. Section 9802.1b requires full compliance with the chapter before any development occurs and declares that violating any of its requirements, including violated conditions and safeguards, constitutes a misdemeanor. Section 9803 designates the Building Official as Floodplain Administrator, responsible for granting or denying development permits, and requires permit applications to show the proposed elevation of the lowest floor relative to mean sea level, or the elevation to which a structure will be floodproofed.

Section 9804 sets the technical standards: new construction and substantial improvements must be anchored against flotation and lateral movement, built with flood-resistant materials, and in Zones A1-30, AE and AH must have the lowest floor elevated to or above the base flood elevation, certified by a registered engineer or surveyor. Residential subgrade-enclosed areas are flatly prohibited as basements under the lowest-floor definition in Section 9802, including below-grade garages. Variances from these standards go to the City Council under Section 9805, which must weigh factors including danger to life and property and availability of alternative non-flood locations, and any variance recipient gets written notice that flood insurance costs will reflect the reduced elevation, recorded against the property's chain of title.