California Code, Public Utilities Code - PUC § 101179

No such taking or acquisition by the district which would involve the abandonment, removal, relocation, or use of the property of a railroad corporation, as defined in Section 230, shall be permitted, unless the Public Utilities Commission, after hearing, shall find and determine that the public interest and necessity require the abandonment, removal, relocation, or use of such property and that such taking or acquisition will not unreasonably impair the ability of the railroad corporation involved to provide safe, adequate, economical, and efficient service.