When bonds issued by a municipality are secured either by ad valorem tax levies or by specific revenues other than ad valorem tax levies and the payment of the tax or specific revenue has been delinquent for a period of 30 years the taxes or revenue shall be presumed to be uncollectable and in those cases, the municipal treasurer shall enter upon the appropriate bond issue records where the bonds appear the words "CANCELLED - Revenue Uncollectable", and shall adjust the books and records accordingly.
When bonds have been designated as specified above the municipality may use any money it holds for the payment of those bonds for any general corporate purpose.
35 ILCS 200/20-185