If a sub­di­vi­sion is planned adja­cent to an exist­ing Coun­ty or Road Dis­trict road, the devel­op­er shall reserve a right-of-way that is a min­i­mum of fifty (50) feet wide from the cen­ter­line of any Coun­ty High­way and a min­i­mum of thir­ty (30) feet wide from the cen­ter­line of any Road Dis­trict road.