The City of Jamestown designated a High Ground Water Table and Impervious Layer Overlay District in which, in order to preserve the town’s fresh water supply, the area has been deemed unsuitable for unrestricted development. The District is divided into two sub-districts: sub-district A has a higher groundwater table, and thus heightened restrictions on development, and sub-district B, a lower groundwater table, and less restrictive development requirements. The ordinance lays out the restrictions on development within each zone, as well as the obstacles to obtaining a variance.