California Code, Code of Civil Procedure - CCP § 1240.230

(a) If the defendant objects to a taking for future use, the burden of proof is as prescribed in this section.

(b) Unless the complaint states an estimated date of use that is not within seven years from the date the complaint is filed, the defendant has the burden of proof that there is no reasonable probability that the date of use will be within seven years from the date the complaint is filed.

(c) If the defendant proves that there is no reasonable probability that the date of use will be within seven years from the date the complaint is filed, or if the complaint states an estimated date of use that is not within seven years from the date the complaint is filed, the plaintiff has the burden of proof that a taking for future use satisfies the requirements of this article.