Mo. Rev. Stat. § 238.245: Property, district may purchase and control access.

The district may, subject to commission or local transportation authority approval, as appropriate:

(1) Purchase land or receive contributions of land and cash for project right-of-way;

(2) Limit and control access from adjacent property to a district project; and

(3) Sell and convey excess right-of-way for fair market value to any person or entity.