El Cerrito Municipal Code Ch. 19.13 Hazard Overlay District (-Hz)

The specific purposes of the -HZ Hazard overlay district are to:

A. Mandate the review, evaluation, and restriction of land use that may be subject to undue risk in areas identified on the City's Hazard Special Study Map, including very high hazard severity zones, flood hazard areas, and geologically hazardous areas as called for by the Tri Cities Seismic Safety Study, published on September 9, 1973.

B. Require soils and geologic review of development proposals to assess potential seismic hazards related to slope stability, earthquake ground shaking, fault ground rupture, and liquefaction potential.

C. Require all geologic hazards be adequately addressed and mitigated through project development.

(Ord. 2008-2 Div. II (part), 2008.)

The provisions of this Chapter shall apply to all areas mapped and identified on the Hazard Special Study Map, commissioned by the City Building Official. The Hazard Special Study Map depicts areas within the City where there are: (1) Seismic and Geologic Hazards based on the 1973 Tri-Cities Study, (2) Very High Fire Hazard Severity Zones; and (3) Flood Hazard Areas. The City Engineer or Building Official may apply requirements of this district to properties outside the -HZ Hazard overlay district if the City Engineer reasonably determines that a potential hazard exists which should be evaluated. More precise information can be found in the Seismic Safety Study for the General Plan, Tri-Cities Seismic Safety and Environmental Resources Study, 1973.

(Ord. 2008-2 Div. II (part), 2008.)

All permit applications for projects located within areas of the -HZ Hazard overlay district more specifically identified as "Active Faults — Earthquake Fault Zone" and "High Landslide Risk Areas" on the Hazard Special Study Map shall require the following reports:

A. New Construction. All new construction shall require a soils report and a geologic report, subject to the requirements of Sections 19.13.040 and 19.13.050.

B. Additions. Any additions to existing structures that require the installation of a foundation, shall require a soils report, subject to the requirements of Section 19.13.040. A soils report may not be required for small additions (less than 50 square feet in floor area), based upon the determination of the City Engineer or Building Official.

C. Miscellaneous Structures and Small Additions. A soils report shall not be required for detached non-habitable structures that total 225 square feet in floor area or less.

(Ord. 2008-2 Div. II (part), 2008.)

A soil report, based upon adequate test borings or excavations, shall be prepared by a civil engineer registered with the State of California, subject to the following requirements:

A. Contents. The soil report shall assess the potential for landsliding, ground shaking, and surface faulting. If the soil report indicates the presence of soil conditions which, if not corrected, could lead to structural defects, the report shall recommend corrective action that is likely to prevent structural damage to each structure proposed to be constructed.

B. Review of Report. The soil report shall be reviewed and approved by the Building Official and/or City Engineer prior to issuance of any building or grading permit. The Building Official may have the soil report independently reviewed by a licensed geotechnical engineer, registered by the state of California, the cost of which shall be borne by the applicant. The recommended action shall be incorporated in the construction of each structure as a condition to the issuance of any building permit.

(Ord. 2008-2 Div. II (part), 2008.)

A geologic report (based on the Alquist-Priolo Earthquake Fault Zoning Act and related regulations, California Public Resources Code Section 2621 et seq., or any successor statutes, and California Code of Regulations, Title 14, Section 3600 et seq., or any successor regulations) shall be prepared by a certified engineering geologist, subject to the following requirements:

A. Content. The report shall identify, describe and illustrate, where applicable, potential hazards of surface fault rupture, seismic shaking, liquefaction or landslide and shall include:

1. Review of Conditions. A review of the local and regional seismic and other geological conditions that significantly affect the proposed use.

2. Assessment. An assessment of conditions on or near the site that would contribute to the potential for damage to a proposed use from a seismic or other geological event, or the potential for a new use to create adverse effects upon existing uses because of identified geologic hazards. The conditions assessed are to include, where applicable, rainfall, soils, slopes, water table, bedrock geology, and any other substrate conditions that may affect seismic response, landslide risk or liquefaction potential.

3. Recommendations. Recommended building techniques, site preparation and mitigation measures, or setbacks necessary to reduce risks to life and structural damage to property from seismic damage, landslide, groundwater and liquefaction to insignificant levels.

(Ord. 2008-2 Div. II (part), 2008.)

No report is required for an application located in an area for which the City Engineer and Building Official determine that sufficient information exists because of previous geology or soils reports. If the application for development is made in connection with a subdivision, any required soils reports shall be prepared pursuant to Title 18, Subdivisions, of the El Cerrito Municipal Code.

(Ord. 2008-2 Div. II (part), 2008.)

All new roof coverings in areas of the -HZ Hazard overlay district identified on the Hazard Special Study Map as "Very High Fire Hazard Severity Zones," shall require at least a Class B rated roof. Wood shingle and wood shake roofing is prohibited in these areas.

(Ord. 2008-2 Div. II (part), 2008.)

New construction and additions in areas of the -HZ Hazard overlay district identified on the Hazard Special Study Map as "Flood Hazard Areas," shall comply with Federal Flood Plain Guidelines for construction in these areas.

(Ord. 2008-2 Div. II (part), 2008.)