All developers of the aforementioned projects shall be required to submit a "yield plan," defined as: a plan demonstrating a subdivision's or land development project's maximum density (maximum number of lots or units), taking into account all environmental, natural and man-made physical constraints to development, including but not limited to wetlands, topography, groundwater characteristics, and existing improvements. A yield plan shall meet all conventional zoning and subdivision requirements, including minimum buildable area requirements, and shall not assume that any waivers, variances or special use permits will be granted. On parcels located in areas not serviced by public sewers and not proposed for extension of public sewers, the yield plan shall include the location of an appropriate on-site wastewater treatment system on each lot.