The plat jurisdiction of the village shall include all land within the corporate limits of the village and all unincorporated land within one and one-half (11/2) miles of the corporate limits of the village, except when a contractual agreement has been established between Sherman and other municipalities concerning jurisdictional powers in the one and one-half (11/2) mile overlap areas between the two (2) municipalities. The village will then have subdivision control in that portion of the overlap area established by the agreement. (1984 Code § 6-1-2)