Cal. WAT § 11590

The department has no power to take or destroy the whole or any part of the line or plant of any common carrier railroad, other public utility, or state agency, or the appurtenances thereof, either in the construction of any dam, canal, or other works, or by including the same within the area of any reservoir, unless and until the department has provided and substituted for the facilities to be taken or destroyed new facilities of like character and at least equal in usefulness with suitable adjustment for any increase or decrease in the cost of operating and maintenance thereof, or unless and until the taking or destruction has been permitted by agreement executed between the department and the common carrier, public utility, or state agency.