The following provisions apply to the governing bodies of flood control districts that, upon creation, have territory in three or more counties:

(1) The governing body shall include one member from each county with territory in the district, and two additional members selected as provided by this section. No more than two governing members may be from the same county.

(2) The initial members of the governing body must be chosen by each county legislative authority within which the district resides, with each county choosing one member, and the two counties with the largest populations within the district choosing one additional member each. The initial governing body members shall serve until their successors are elected and qualified at the next special district general election.

(3) At this first election, the members receiving the two greatest number of votes shall serve six-year terms, the members receiving the third and fourth greatest number of votes shall serve four-year terms, and the remaining members shall serve two-year terms of office.

(4) The requirements for the filing period, method for filing declarations of candidacy, and the arrangement of candidate names on the ballot for all special district general elections conducted after the initial election in the district shall be the same as the requirements for the initial election in the district. No primary elections may be held for the governing body of a flood control district that, upon creation, has territory in three or more counties.

(5) A vacancy occurs upon the death, resignation, or incapacity of a governing body member, or whenever the governing body member ceases to be a registered voter of the district.

(6)(a) Whenever a vacancy occurs in the governing body, the legislative authority of the county within which the largest geographic portion of the district is located shall appoint a registered voter to serve until a person is elected, at the next special district general election occurring sixty or more days after the vacancy has occurred, to serve the remainder of the unexpired term. The person so elected shall take office immediately when qualified as defined in RCW 29A.04.133.

(b) If an election for the position that became vacant would otherwise have been held at this special district general election, only one election shall be held and the person elected to fill the succeeding term for that position shall take office immediately when qualified as defined in RCW 29A.04.133 and shall serve both the remainder of the unexpired term and the succeeding term.

(7) An elected or appointed member of the governing body, or a candidate for the governing body, must be a registered voter of the flood control district who has resided within the district for [a] period of not less than thirty days before the election. In accordance with RCW 85.38.127, land ownership is not a requirement for serving on the governing body of the district.