Cal. Harb. & Nav. Code § 6031

The board of supervisors, by resolution, shall fix the date of the election, which shall not be less than 130 days from the date of its passage and it shall divide the proposed district into one or more voting precincts and generally describe or otherwise designate the boundaries of each precinct and designate a place within each precinct at which the polls will be opened for the purpose of the election on the day of the election.