Permit Requirements
Any development within the SFHA is subject to federal and City floodplain management requirements. Always check with the City's Land Development Engineering Division at 408-586-3325 before you build on, alter, re-grade or place fill on your property.
Report illegal floodplain development activity to the Building Department at 408-586-3240 or the City's Land Development Engineering Division via phone at 408-586-3313.
Floor Elevation
New buildings in the SFHA must have their lowest floor elevation (excluding garage) flood-proofed or raised a minimum of one foot above the base flood (100-year) elevation.
Substantial Improvement (SI)
Substantially improved structures in the SFHA must meet the same floodplain construction requirements as new buildings. SI is defined as any reconstruction, rehabilitation, attached addition, or other improvement of an existing structure, the cost of which equals or exceeds 49 percent of the fair market value of the structure before the start of the new construction. Improvements to any structure within the SFHA are cumulatively tracked for 10 years.
If the property is within SFHAs, City Land Development Engineering Sector shall request and obtain the following documentation from the applicants:
(a) One copy of the most recent professional Property Appraisal Report that is less than 3 months old and signed by a licensed Real Estate Appraiser in the State of California.
(b) One copy of a completed and signed SI Declaration Form. The unit cost of the building, based on the building permit unit cost, can be referred to Building Valuation Data.
(c) One copy of the site improvement plan. The improvement plan shall be to scale and depict the existing condition as well as the addition(s).
Substantial Damage (SD)
Substantially damaged structures (a structure damaged so that the cost of repairs equals or exceeds 49 percent of the structure’s value before it was damaged) in the SFHA must also meet the same floodplain construction requirements as new buildings.
To find out more about the requirements, for construction in the floodplain, please contact the City's Land Development Engineering Division via phone at 408-586-3313.
For information on selecting a qualified architect, engineer, or contractor, call the City Building Department at 408-586-3240.
FEMA Useful Document
Substantial Improvement / Substantial Damage Desk Reference FEMA P-758 / May 2010
Wet Floodproofing Requirement and Limitations, NFIP Technical Bulletin 7 / May 2022
Dry Floodproofing Technical Review, March 2022