Cal. Wat. Code § 55659
A copy of the petition shall be filed with the county engineer of waterworks districts, or district engineer if one has been appointed, at least two weeks before the petition is presented to the board. The county engineer of waterworks districts or district engineer, as the case may be, shall prepare and file with the board, at least one week before the date set for the hearing on the petition, a report containing cost estimates and preliminary plans and specifications for the proposed improvements, together with any recommendations as to the boundaries of the proposed zone, and any other pertinent information relating to the feasibility of the proposed improvements or proposed zone. The engineer's report shall be available in the office of the board for public inspection, and may be considered by the board at the hearing on the petition.
Ca. Water Code § 55659