Mo. Rev. Stat. § 249.1154
The governing body of any county, by order or ordinance or upon the filing of a petition signed by at least twenty percent of the property owners in an area proposed for designation under this section, may designate groundwater depletion areas within a watershed improvement district created under section 249.1150 or 249.1152 and may require well volume monitoring.
(L. 2004 H.B. 1433)