California Code, Water Code - WAT § 50780.18

(a) The manner in which the trustees shall be elected at the 1997 district election, and at every district election thereafter, depends on the percentage of land in the district that is used for agricultural purposes that is subject to an assessment pursuant to Article 3 (commencing with Section 51320) of Chapter 2 of Part 7 in accordance with subdivisions (b), (c), and (d).

(b) Between 180 and 200 days before the election, the board shall determine whether the percentage of land described in subdivision (a) has equaled or exceeded 35 percent during the immediately preceding two years.  If so, the board shall designate four seats as “land assessment seats” and three seats as “parcel seats.”

(c) Between 180 and 200 days before the election, the board shall determine whether the percentage of land described in subdivision (a) has been below 35 percent and has equaled or exceeded 20 percent during the immediately preceding two years.  If so, the board shall designate four seats as “parcel seats” and three seats as “land assessment seats.”

(d) Between 180 and 200 days before the election, the board shall determine whether the percentage of land described in subdivision (a) has been below 20 percent during the immediately preceding two years.  If so, the board shall designate five seats as “resident voter seats” and two seats as “land assessment seats.”