35 ILCS 200/15-140: Public water districts and water and drainage works.

All property belonging to any public water district organized or existing under the Public Water District Act is exempt, as is all property belonging exclusively to any incorporated town, village or city, and used exclusively for conveying water to the incorporated town, village or city, and all property of drainage districts, when used exclusively for pumping water from the ditches and drains of the district for drainage purposes.