70 ILCS 605/5-20.1

In districts where the county collector collects all drainage assessments provided for by this Act, it shall be the duty of the drainage district commissioners to cause an examination of county general tax records at least once each year to ascertain any changes in ownership of land within the district. Any assessment roll or certificate of levy of annual maintenance assessment filed pursuant to this Act shall be accompanied by an affidavit of the commissioners stating that the search required by this Section has been made during the preceding year and that information in the assessment roll as to tract descriptions and names and addresses of land owners or persons who last paid general taxes on lands coincides with information shown in the county general tax records.