70 ILCS 605/7-12
Minor subdistricts may be organized in such particular localities or separate areas within subdistricts as may require more minute or complete drainage or protection than is provided by the drainage system of the subdistrict. The proceedings for the organization of minor subdistricts shall be carried on in like manner and with like effect as is herein provided for the organization of subdistricts. The commissioners and other officers of the main district, ex officio, shall be commissioners and officers of minor subdistricts, and they shall have the same powers and duties as are provided in this Act for commissioners and other officers of main districts but they shall keep a separate record of their acts and doings affecting each minor subdistrict. The funds of a minor subdistrict shall not be commingled with the funds of the main district, any subdistrict or any other minor subdistrict.
70 ILCS 605/7-12