Code Civ. Proc., § 751.51

(a) An action authorized by this chapter may be commenced by:

(1) A county in which lands were affected by a disaster described in Section 751.50 with or without the joinder of a city or cities included in the county and within the area so affected.

(2) A city, if the disaster has affected land in the city.

(3) Any other entity or person owning or having an interest in or lien upon land affected by the disaster if granted permission by the court to bring the action, and if the county in which the land is located is made a party to the action.

(b) In an action authorized by this chapter every entity in actual and peaceable possession of, or having an estate or interest in or lien upon any of the land affected by the action, whose possession or evidence of estate or interest is either recorded or known to the plaintiffs, the city, if the land is within a city, the county in which the land is located, and the State of California must be designated in the complaint of the action, and given notice in the manner required by this chapter.

(c) All unknown entities, including owners, lien or interest claimants, heirs, devisees, legatees or assigns, may be described in the caption and complaint as “all entities claiming any interest in or lien upon, the real property herein described or any part of it.”