Mo. Rev. Stat. § 226.955
Any corridor map filed pursuant to sections 226.952 to 226.957 may be revised from time to time by filing with the same regulatory authorities and county recorders who received the prior corridor map, in the manner set forth in sections 226.952 to 226.957, certified copies of an amended corridor map indicating any changes to be made in the location of the highway corridor. In the event that the commission fails to initiate construction on any portion of the new or relocated highway which was to be located within the approved corridor within ten years after the original copy of the corridor map is filed under sections 226.952 to 226.957, the commission shall, in accordance with section 226.967, dispose of any property acquired by the commission within the approved corridor.
§ 226.955, RSMo