Upon the filing with the county legislative authority of each county in which the district is located of a resolution of any governmental unit calling for the disincorporation of a special district, or upon the filing with the county legislative authority of each county in which the district is located of the petition of twenty percent of the voters within a special district calling for the disincorporation of the special district, the county legislative authority shall hold public hearings to determine whether or not any services have been provided within a consecutive five year period and whether the best interests of all persons concerned will be served by the proposed dissolution of the special district.