Lot size and shape, residential unit placement, and other dimensional requirements within an open space subdivision are flexible, subject to the following guidelines and limitations:
A. Objectives. Residential units shall be located and arranged in a way that advances the open space and resource conservation objectives of this by-law, i.e., to protect views from roads and other publicly accessible points; farmland; wildlife habitat; large intact forest areas; hilltops and steep slopes; ponds, wetlands and groundwater resources; and other sensitive environmental resources.
B. Monumentation. Monumentation of a type consistent with the use of the open space, and approved by the Planning Board, shall clearly delineate the boundaries of the protected open space in a manner that facilitates monitoring and enforcement.
C. Area. There is no required minimum lot size for zoning purposes. The limiting factors on lot size and placement for each single-family structure or specially permitted duplex in an open space subdivision are the need for adequate water supply and sewage disposal for each residential unit; protection of the quality and quantity of current and future groundwater resources on abutting properties; prevention of negative impacts on wetlands on or near the subdivision; and compliance with the other provisions of this by-law.
D. Infrastructure. Water, wastewater infrastructure and stormwater management for an OSRD shall be subject to the by-laws and rules and regulations of the Planning Board, the Board of Health, the Department of Public Works, and the Conservation Commission. To minimize environmental impacts, where practicable, residential units shall have shared or clustered septic systems.
E. Frontage. On existing public roads, frontage of any open space subdivision lot shall be as required for a conventional lot in the relevant zoning district. On internal open space subdivision roads, there is no numerical requirement for lot frontage. Each lot must have legal and functional vehicular access to an existing public road or an internal open space subdivision road approved under the Subdivision Rules and Regulations, either directly across its own frontage or via a common driveway approved by special permit.
F. Setbacks. The minimum setback of any building from an existing public road shall be 100 feet. The minimum setback of any building from an internal open space subdivision road shall be 30 feet. The minimum setback of any building from the property line of an abutting property not part of the open space subdivision shall be 60 feet. The minimum distance between residential buildings within the open space subdivision shall be 30 feet. The minimum distance between an open space subdivision residential building and an abutter's residential building shall be 100 feet.