70 ILCS 1205/9.3-5
Each park district which issues bonds and acquires or constructs, extends or improves indoor or outdoor recreational facilities under the provisions of this Article shall charge for the use thereof at a rate which at all times is sufficient to pay maintenance and operation costs, depreciation, and the principal and interest on the bonds. Such district may make, enact and enforce all needful rules and regulations for the construction, acquisition, improvements, extension, management, maintenance, care and protection of the facility and for the use thereof. Charges or rates for the use of the facility shall be such as the board may from time to time determine.
While any bond issued under Section 9.3-1 is outstanding such district is required to maintain and operate the facility as long as it can do so, out of the revenue derived from the operation thereof. It shall not sell, lease, loan, mortgage or in any other manner dispose of the facility or facilities until all of the bonds so issued have been paid in full, both principal and interest, or until provision has been made for the payment of all of the bonds and interest thereon in full.
Such park district shall install and maintain a proper system of accounts, showing the amount of revenue received from the operation of the facility. At least once each year, the district shall have the accounts properly audited. A report of this audit shall be open for public inspection at all times.
70 ILCS 1205/9.3-5