The governing body of a county in the Commonwealth, upon the petition of 50 qualified voters of a proposed district or, if the proposed district contains less than 100 qualified voters, upon petition of 50 percent of the qualified voters of the proposed district, may, by ordinance, create a sanitary district or districts in and for the county, which ordinance shall prescribe the metes and bounds of the district. With the approval of the board of supervisors of a county and the council of any town therein, such town or any part thereof may be included within a sanitary district created or enlarged under the provisions of this chapter.