California Code, Water Code - WAT § 12878.7

The board or department shall prepare a description of the proposed boundaries together with a map thereof for each maintenance area to be formed.  For the purpose of preparing these boundaries and this map, the board or department shall make such investigations as may be necessary and may utilize any and all books, maps, or other relevant records, whether or not on file in the offices of the board or department or any other office or agency of the State.  All officers or agencies of the State shall render whatever assistance may be required to facilitate the work of the board or department pursuant to the provisions of this chapter.