Mo. Rev. Stat. § 67.1700
A metropolitan park and recreation district may be created, incorporated and managed pursuant to sections 67.1700 to 67.1769 and may exercise the powers given to such district pursuant to sections 67.1700 to 67.1769. Such a metropolitan district may include and is limited to any county of the first classification with a charter form of government and having a population of at least nine hundred thousand inhabitants according to the last decennial census, or any county within the standard metropolitan statistical area of any such county. Any county described in this section may be included in a metropolitan district if the voters in the county or counties to be included in the district vote, pursuant to sections 67.1715, 67.1718 and 67.1721, to be included in such district. Any recreation system or public parks system which exists within a metropolitan district created pursuant to sections 67.1700 to 67.1769 shall remain in existence with the same powers and responsibilities it had prior to the creation of the metropolitan district. Nothing in sections 67.1700 to 67.1769 shall be construed in any manner to limit or prohibit:
§ 67.1700, RSMo