65 ILCS 5/11-75-3

Any building erected in the space leased, by exercise of the power granted by Section 11-75-1, which is above or around buildings located on land owned or otherwise held by the municipality shall be operated, as far as practicable, separately and apart from any building owned or operated by the municipality. No liability shall in any manner attach to the municipality by reason of the erection or operation of the building in the space so leased.