Chapter 5 OVERLAY ZONES This chapter is included in your selections. Sections: 5.010 Purpose. 5.020 Applicability of Overlay Zones. 5.030 Flood Plain Overlay Zone. 5.040 Historic District Overlay Zone. 5.050 Theater District Overlay Zone. 5.060 Senior Mobile Home Park Overlay District. 5.080 Fairgrounds Overlay Zone.