70 ILCS 1105/19
Any appropriation or levy made for the purpose of constructing, restoring, reconditioning, reconstructing, or acquiring improvements and for the development of historical sites, together with related lands and facilities, of the district need not be expended during the fiscal year in which the appropriation or levy is made. The appropriation does not lapse and the moneys levied, collected, or received for that purpose do not become part of the general funds of the district for a period of 5 years and are not available for appropriation in a later fiscal year, but shall be retained and held in a separate fund for 5 years to be expended within that time for the purpose for which appropriated and levied. After 5 years the moneys become a general asset available for appropriation for general corporate purposes. It is not a defense or objection to any appropriation or levy for the same purposes in a later fiscal year that there remain uncommenced or uncompleted projects or unexpended moneys arising in an appropriation or levy of an earlier year for purposes of this Section, unless the period of 5 years after the fiscal year in which the appropriation was made has elapsed.
70 ILCS 1105/19