To be eligible for reassessment the damage or destruction to the property shall have been caused by any of the following:
The application for reassessment may be filed within the time specified in the ordinance or within 12 months of the misfortune or calamity, whichever is later, by delivering to the assessor a written application requesting reassessment showing the condition and value, if any, of the property immediately after the damage or destruction, and the dollar amount of the damage. The application shall be executed under penalty of perjury, or if executed outside the State of California, verified by affidavit.
An ordinance may be made applicable to a major misfortune or calamity specified in paragraph (1) or to any misfortune or calamity specified in paragraph (2), or to both, as the board of supervisors determines. An ordinance shall not be made applicable to a misfortune or calamity specified in paragraph (3), unless an ordinance making paragraph (2) applicable is operative in the county. The ordinance may specify a period of time within which the ordinance shall be effective, and, if no period of time is specified, it shall remain in effect until repealed.
If partial reconstruction, restoration, or repair has occurred on any subsequent lien date, the taxable value shall be increased by an amount determined by multiplying the difference between its factored base year value immediately before the calamity and its assessed value in its damaged condition by the percentage of the repair, reconstruction, or restoration completed on that lien date.
Ca. Rev. and Tax. Code § 170