California Code, Code of Civil Procedure - CCP § 1273.030

(a) Except as specifically provided in this chapter, agreements authorized by this chapter are subject to Title 9 (commencing with Section 1280) of this part.

(b) An agreement authorized by this chapter may be made whether or not an eminent domain proceeding has been commenced to acquire the property. If a proceeding has been commenced or is commenced, any petition or response relating to the arbitration shall be filed and determined in the proceeding.

(c) Notwithstanding Section 1281.4, an agreement authorized by this chapter does not waive or restrict the power of any person to commence and prosecute an eminent domain proceeding, including the taking of possession prior to judgment, except that, upon motion of a party to the proceeding, the court shall stay the determination of compensation until any petition for an order to arbitrate is determined and, if arbitration is ordered, until arbitration is had in accordance with the order.

(d) The effect and enforceability of an agreement authorized by this chapter is not defeated or impaired by contention or proof by any party to the agreement that the party acquiring the property pursuant to the agreement lacks the power or capacity to take the property by eminent domain.

(e) Notwithstanding the rules as to venue provided by Sections 1292 and 1292.2, any petition relating to arbitration authorized by this chapter shall be filed in the superior court in the county in which the property, or any portion of the property, is located.