A county that is not a member county may join a district in accordance with this section. To join a district, the governing body of the incoming county shall adopt an ordinance or resolution that asks the district to admit the incoming county. If the sanitary commission of the district adopts a resolution that approves the admission of the incoming county and if the governing body of each member county adopts an ordinance or resolution that approves the admission of the incoming county, the sanitary commission and the governing body of the incoming county shall adopt and sign articles of joinder. Immediately on the admission of the county, the governing body of the new member county shall appoint a sanitary commissioner. The articles of joinder shall include: The name, address, and term of office of the first sanitary commissioner from the incoming county; and All information about the incoming county that would be required in original articles of incorporation. The district and incoming county shall file the articles of joinder with the State Department of Assessments and Taxation.