Chapter 20.510 HERITAGE OVERLAY DISTRICT This chapter is included in your selections. Sections: 20.510.010 Purpose. 20.510.020 Heritage Overlay District Number One – Standards and Guidelines. 20.510.030 Review Process. 20.510.040 Determination of Compliance. 20.510.050 Preservation, Restoration and Reuse. 20.510.060 Identification Plaque.