A. The area of any parcel generally suitable, in its natural state, for development and theoretically related to the natural capacity of the land to support a certain intensity of use. The net acreage shall be determined by subtracting unsuitable areas from the gross acreage of the parcel. The following original land areas shall be considered unsuitable and shall be deducted in the following order:
(1) Fifteen percent of the total acreage of the parcel as an estimated allowance for new access roads and parking areas, whether or not the actual area devoted to these uses is greater or less than 15%.
(2) Areas that are, because of existing land uses, natural features or lack of access, isolated and unavailable for building purposes or for use in common with the remainder of the parcel, as determined by the Town Planner, whose determination is subject to Planning Board review in the event of a dispute.
(3) Areas within a floodway or 100-year flood hazard area, as shown on the Federal Flood Boundary and Floodway Map or Federal Flood Insurance Rate Map.
(4) Wetland areas, defined as hydric soil in conjunction with hydrophytic vegetation, or land which has been created by filling or draining a wetland or pond.
(5) Areas of rights-of-way and easements, except for new access roads deducted above and rights-of-way or easements for landscaped buffer strips and walking/bicycle paths not part of a street right-of-way.
(6) Stream channels, as measured from the top of banks, and other surface water bodies, as measured from the high water mark.
(7) Areas of sustained slope of more than 33%. Slope areas of 20% to 33% shall also be deducted unless the developer can demonstrate to the Planning Board's satisfaction that these slopes will be used as part of the overall plan for the development, that they are stable for structures, if so utilized, and that any slope development will minimize soil erosion and comply with Maine State Plumbing Code.
(8) Areas of unreclaimed gravel or borrow pits.
(9) Areas with very poorly drained soils areas, as measured from a Class A high-intensity soils survey as identified under Maine Association of Professional Soil Scientists guidelines for Maine Certified Soil Scientists for Soil Identification and Mapping.
(10) For sites not served by public sewer and water, 50% of the areas with poorly drained soils, and 25% of the areas with soils with multiple drainage classifications, one of which is poorly drained (i.e., poorly drained to somewhat poorly drained), as measured from a high-intensity soils survey and map prepared by a certified soil scientist in accordance with the Maine Association of Professional Soil Scientists guidelines for Maine Certified Soil Scientists for Soil Identification and Mapping. This deduction is to account for the marginal development suitability of these soils if public sewer and water are not available.
(11) Other areas that the Planning Board determines could not, in their natural state, be incorporated into conventional subdivision lots of the minimum required area.
B. No building or structure shall be sited in areas treated as 100% deductions from the parcel's gross area. Siting of structures in areas treated as 50% deductions shall be discouraged but permitted where the applicant/developer demonstrates that measures will be taken to minimize erosion, sedimentation and seasonal wetness, that these areas are stable for the siting of structures and that proposed subsurface waste disposal systems are sited away from marginal soils and otherwise meet the State of Maine Subsurface Wastewater Disposal Rules.
