65 ILCS 5/11-132-2
Whenever, in the judgment of a majority of any board of water commissioners, or if there is no such board, whenever in the judgment of a majority of the city council of any city specified in Section 11-132-1, it is necessary for the public health, or for any other cause, to increase the source of water supply, or to substitute for it such better source as in their judgment the interests of the city may demand, the board of water commissioners or the city council may dig wells, either by boring or excavation, and protect and equip them, or they may lease water privileges from persons owning wells already or hereafter to be dug. Subject to the provisions of Section 11-132-3, the board of water commissioners or the city council may pay for the boring, excavation, or lease, and for the expenses incurred in maintaining and operating the wells, only out of the surplus earnings of the city's waterworks.
65 ILCS 5/11-132-2