CA Civ Proc Code Section 751.58

The vacating of streets, highways or other public ways within or abutting the area affected by the disaster, in whole or in part, by the voluntary action of the governmental agency under whose jurisdiction the streets, highways, or ways are vested, for the purpose of making it possible for the court to mitigate the hardships suffered by entities because of the change in land boundaries caused by the disaster can be accomplished by the affected governmental agency expressing the offer in the proceedings followed by the court’s acceptance thereof in an action authorized by this chapter, without complying with any other formalities of law.