Illinois Statutes Chapter 35. Revenue § 200/10-155. Open space land; valuation

§ 10-155. Open space land; valuation. In all counties, in addition to valuation as otherwise permitted by law, land which is used for open space purposes and has been so used for the 3 years immediately preceding the year in which the assessment is made, upon application under Section 10-160, shall be valued on the basis of its fair cash value, estimated at the price it would bring at a fair, voluntary sale for use by the buyer for open space purposes.

Land is considered used for open space purposes if it is more than 10 acres in area and:

Land is not considered used for open space purposes if it is used primarily for residential purposes.

If the land is improved with a water-retention dam that is operated primarily for commercial purposes, the water-retention dam is not considered to be used for open space purposes despite the fact that any resulting man-made lake may be considered to be used for open space purposes under this Section.