Lafayette Municipal Code Art. 3 Administration

A development permit must be obtained before construction or development begins within any area of special flood hazard established in Section 6-1812. Application for a development permit shall be made on forms furnished by the city engineer and may include, but not be limited to: plans drawn to scale showing the nature, location, dimensions and elevation of the area in question; existing or proposed structures, fill, storage of materials, drainage facilities; and the location of the foregoing. Specifically, the following information is required:

(a) Site plan, including, but not limited to:

(1) For all proposed structures, spot ground elevations at building corners and 20-foot or smaller intervals along the foundation footprint, or one-foot contour elevations throughout the building site; and

(2) Proposed locations of water supply, sanitary sewer and utilities; and

(3) If available, the base flood elevation from the flood insurance study and/or flood insurance rate map; and

(4) If applicable, the location of the regulatory floodway; and

(5) Proposed impervious paving or other impervious surfaces; and

(b) Foundation design detail, including, but not limited to:

(1) Proposed elevation, in relation to mean sea level, of the lowest floor (including basement) of all structures;

(2) For a crawl-space foundation, location and total net area of foundation openings as required in Section 6-1834(d) and FEMA Technical Bulletins 1-93 and 7-93; and

(3) For foundations placed on fill, the location and height of fill, and compaction requirements (compacted to 95 percent using the Standard Proctor Test method); and

(c) Proposed elevation, in relation to mean sea level, to which any nonresidential structure will be floodproofed as required in Section 6-1834(c) and FEMA Technical Bulletin TB 3-93;

(d) All appropriate certifications listed in Section 6-1823(c) of this chapter; and

(e) Description of the extent to which any watercourse will be altered or relocated as a result of proposed development.

(Ord. No. 684, § 2(Exh. 2), 4-10-2023)

The Lafayette city engineer is appointed to administer, implement and enforce this chapter by granting or denying development permit applications in accordance with its provisions.

(Ord. No. 684, § 2(Exh. 2), 4-10-2023)

The duties of the floodplain administrator include, but are not limited to:

(a) Permit Review. Review of development permits to determine that:

(1) The permit requirements of this chapter are satisfied;

(2) All other required state and federal permits have been obtained;

(3) The site is in compliance with local, state and federal floodplain regulations;

(4) The proposed development does not adversely affect the carrying capacity of areas where base flood elevations have been determined but a floodway has not been designated. For purposes of this chapter, "adversely affects" means that the cumulative effect of the proposed development when combined with all other existing and anticipated development will increase the water surface elevation of the base flood more than one foot at any point.

(b) Review, Use, and Development of Other Base Flood Data.

(1) When base flood elevation data has not been provided in accordance with Section 6-1812, "Basis for establishing the areas of special flood hazard," the city engineer shall obtain, review and reasonably utilize any base flood elevation and floodway data available from a federal or state agency, or other source, in order to administer Article 4 of this chapter. Any such information shall be submitted to the city council of the city for adoption.

(2) If no base flood elevation data is available from a federal or state agency or other source, then a base flood elevation shall be obtained using one of two methods from the FEMA publication "Managing Floodplain Development in Approximate Zone A Areas - A Guide for Obtaining the Developing Base (100-year) Flood Elevations" dated July 1995 in order to administer Article 4:

(A) Simplified Method.

(i) One hundred-year or base flood discharge shall be obtained using the appropriate regression equation found in a U.S. Geological Survey publication, or the discharge-drainage area method; and

(ii) Base flood elevation shall be obtained using the Quick-2 computer program developed by FEMA; or

(B) Detailed Method.

(i) One hundred-year or base flood discharge shall be obtained using the U.S. Army Corps of Engineers' HEC-HMS computer program; and

(ii) Base flood elevation shall be obtained using the U.S. Army Corps of Engineers' HEC-RAS computer program.

(c) Information to be Obtained and Maintained. The city engineer shall obtain and maintain for public inspection and make available as needed the following:

(1) The certified elevation required in Section 6-1834(a) and (b), and Section 6-1838 (Lowest-floor elevations);

(2) The floodproofing certification required in Section 6-1834(c) (Elevation or floodproofing of nonresidential structures);

(3) The certification required in Section 6-1834(d) (Wet floodproofing standard);

(4) The certification required in Section 6-1837(b) (Subdivision standards);

(5) The certification required in Section 6-1839(a) (Floodway encroachments);

(6) The certification required in Section 6-1834(a), (b), or (c) (Elevations in areas of shallow flooding).

(d) Alteration of Watercourses. Whenever a watercourse is to be altered or relocated, the city engineer shall:

(1) Notify adjacent communities and the California Department of Water Resources prior to any alteration or relocation of a watercourse,

(2) Submit evidence of such notification to the Federal Insurance Administration, Federal Emergency Management Agency; and

(3) require that the flood-carrying capacity of the altered or relocated portion of such watercourse is maintained.

(e) Interpretation of FIRM Boundaries. The city engineer shall make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazard. Where there appears to be a conflict between a mapped boundary and actual field conditions, grade and base flood elevations shall be used to determine the boundaries of the special flood hazard area. The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in Section 6-1852(b).

(f) Take action to remedy violations of this chapter as specified in Section 6-1813 of this chapter.

(Ord. No. 684, § 2(Exh. 2), 4-10-2023)

Where uncertainty exists regarding the interpretation of a provision of this chapter or its application to a specific site, the city engineer shall determine the intent of the provision. The city council shall hear and decide appeals when it is alleged there is an error in any requirement, decision or determination made by the floodplain administrator in the enforcement or administration of this chapter.

(Ord. No. 684, § 2(Exh. 2), 4-10-2023)