No later than July 1, 2001 and no less frequently than every ten years thereafter, Council shall, by legislation, divide or redivide the City into four wards for the purpose of electing four ward Council members at the next regular municipal election. The division or re-division of the City into four wards shall provide for substantially equal population in each ward.
      All wards shall be bounded, to the extent possible, by county lines, streets, alleys, avenues, public grounds, canals, water-courses, municipal boundary lines, center lines of platted streets or railroads, or lot lines of platted subdivisions.
      Re-division of the City into wards shall not terminate or otherwise affect the unexpired terms of ward Council members; however, at succeeding elections, ward Council members shall be elected from the wards as reapportioned or re-established under this Section.
   (d)   CENSUS.
      Council shall have the power to cause a census of the City to be taken if it determines a census is necessary for the proper apportionment of the City's wards. Council may authorize officials and employees of the City, independent contractors or state or federal government agencies to conduct the census under the control and direction of Council.