All subdivisions shall adhere to the principles of correct land use, sound planning, and good engineering, and shall meet the requirements of public safety, including reasonable precautions against possible natural disasters, traffic safety and convenience, adequate water supply, stormwater drainage and protection against flooding, and sanitary sewage disposal and be designed with due regard to the rights, health and welfare of the residents of the Town, including the future residents of such subdivisions.
All subdivisions shall be designed and improvements made by the developer shall accomplish the following:
Reduce, to the extent reasonably possible:
Volume of cut and fill.
Area over which existing vegetation will be disturbed; especially if within 200 feet of a river, pond or stream or having a slope of more than 15%.
Number of mature trees removed.
Extent of waterways altered or relocated.
Visual prominence of man-made elements not necessary for safety or orientation.
Erosion and siltation.
Number of driveways exiting onto existing streets.
Disturbance of important wildlife habitats, outstanding botanical features, and scenic or historic environs.
Increase, to the extent reasonably possible:
Vehicular use of collector streets to avoid traffic on streets providing house frontages.
Visual prominence of natural features of the landscape.
Legal and physical protection of views from public ways.
Street layout facilitating south orientation of houses.
Use of curvilinear street patterns.
Adherence to plans. All subdivisions shall be laid out so as to conform to the Master or General Plan for the Town or any part thereof adopted by the Planning Board, and to the requirements of the Planning Board and the rules and specifications of other boards and officials of the Town acting within their jurisdiction. Where such action is deemed by the Board to be in the public interest and in consideration of alternative improvements, the Planning Board may waive the specific requirements of these rules and regulations and of plans adopted by the Board.
Subdivision costs. All expenses for advertising, engineering and design, plans, hearings, reviews, acquisition of necessary rights, construction and other improvements within the subdivision, recording and filing of plans and other documents, and all other expenses in connection with or for a subdivision shall be borne by the applicant.
Preservation of Town character. It is a policy of the Town and a major objective of the Board to preserve to the maximum extent feasible the open, rural character of the Town and its significant natural features and to minimize removal of healthy trees and stone walls, excessive grading and destruction of natural vegetated surfaces.
Layout, location and alignment.
All proposed and existing streets in a subdivision shall be designed and laid out so that they will provide, in the opinion of the Planning Board, for public safety and a convenient and attractive layout.
All proposed and existing streets in a subdivision shall be classified by the Planning Board according to their function and the traffic they will be expected to carry (see § 244-2, Definitions) and the design, alignment and construction of all subdivision streets shall be in accordance with these rules and regulations.
All streets shall be designed and constructed to the end of the layout or to the boundaries of the subdivision, so as to provide a continuous, connecting network with other existing and proposed streets. Where an existing street ends within 250 feet of the subdivision border, and a connection is necessary for the safety and convenience of traffic, the Board may require that a subdivision street be extended to connect to such existing street. Reserve strips preventing access to a street from the adjacent property shall not be permitted, except where, in the opinion of the Planning Board, such reserve strip is in the public interest.
Dead-end streets shall not exceed the lesser of 1,000 feet from the side line of the intersecting street to the street side line at the end of the turnaround, measured along the center line of the street extended, or the minimum length necessary to accommodate 12 lots with the minimum permitted frontage along both sides of such street. This limitation shall apply to any subdivision with a single street exit, whether terminating in a turnaround or involving loops or branching side streets, except that only 1/2 the length of any loop shall be included in calculating the length of a dead-end street. Dead-end and horseshoe-shaped streets are appropriate where a through street connection is not required.
Street jogs with center-line offsets of less than 150 feet between two streets joining the third street from the opposite sides shall be avoided.
Streets shall be laid out so as to intersect as nearly as possible at right angles, but in no instance at an angle of less than 60° for a distance of at least 100 feet from the intersection of center lines.
Where the street grade exceeds 4% (four feet vertically per 100 feet horizontally), a leveling area of not more than two-percent grade shall be provided for a distance of 75 feet from the side line of the intersecting street right-of-way.
Changes in grade shall be by means of vertical curves such as to allow an adequate sight distance.
Residential streets defined as minor, local and minor collector shall conform to the topography of the land and avoid straight segments of more than 400 feet which encourage high speeds and detract from the appearance of residential areas.
With the exception of locations expected to have traffic lights installed, T-intersections shall be used in preference to four-way intersections. Intersections involving more than four approach ways will only be approved when no reasonable alternative is possible.
Dead-end streets shall be designed with a circular turnaround with a pavement radius of at least 50 feet. Other turnaround designs capable of accommodating a vehicle with a fifty-foot turning radius may be allowed by the Board.
Dead-end streets longer than otherwise permitted may be approved where access and egress are provided by means of two parallel twenty-foot-wide pavements separated by a median at least 10 feet wide.
Editor's Note: Original Subsection 4.2.2. Design Standards for Various Street Classifications, which originally followed this subsection, is included as an attachment to this chapter.
Curb cuts for driveways shall be avoided and kept to a minimum along arterial and major collector streets. Curb cuts and utility connections in state highways require approval of the Massachusetts Department of Public Works; opening a Town way requires the approval of the Superintendent of Highways and may require the posting of a bond to guarantee restoration.
Editor's Note: Now the Department of Transportation.
Curb cuts for driveways shall be at least 10 feet wide and shall have three feet radius flare at the pavement. Driveway roundings shall be provided with the same type of curbing as the pavement at that location.
No driveway openings shall be located within 65 feet of the intersection of the center lines of intersecting streets.
Between the side line of the street right-of-way and the edge of the pavement or gutter line, driveway grades shall be not less than 1%, nor more than 8%.
Before approval of a plan, the Planning Board may require either of the following:
The plan to show a park or parks, suitably located in the Board's opinion for playground or recreation purposes or to provide light and air. The Planning Board may require by appropriate endorsement on the plan that no building be erected upon such park or parks without its approval for a period of three years. Each area reserved for such purposes shall be of suitable size, dimension, topography and natural character. The Board may require that the areas so reserved shall be located so as to be used in conjunction with similar areas of adjoining or potential subdivisions and to serve adequately all parts of the subdivision, as approved by the Planning Board. Unless otherwise specified by the Board, the total area to be reserved for park and playground purposes shall be not less than 10% of the gross area of the subdivision. The land so reserved shall not be a wetland and shall not be stripped or altered, except as may be approved by the Board to ensure suitability for the purposes intended.
Certain portions of each lot, collectively equal to no less than 10% of the gross area of the subdivision, shall be set aside under covenant, not to be developed and to remain as open space in its natural state in perpetuity.
Where utilities cross lots or are centered on rear or side lot lines, easements shall be provided of a width of at least 30 feet.
Where a subdivision is traversed by a watercourse, drainage-way, channel or stream, the Planning Board may require a stormwater easement or drainage right-of-way of at least 30 feet and proper side slope to conform substantially to the lines of such watercourse, drainageway, channel or stream and to provide for construction or other necessary purposes.
Easements shall be provided if required by the Planning Board, and shall be at least 30 feet wide.
Lot drainage. Lots shall be prepared and graded in such a manner in accordance with the approved topographic plans that the development of one lot shall not interfere with the proper drainage of other lots and will not cause ponding or flooding. Earthwork and paving shall be kept to a minimum in order to preserve the natural precipitation retention capacity of the soil and reduce impervious areas. If provision is necessary to carry drainage to or across a lot, an easement of at least 30 feet and proper side slope shall be provided. The applicant shall furnish evidence that adequate provision has been made for the proper drainage of surface and underground waters from such lot or lots.
The definitive plan shall show surface and subsurface storm drains, culverts, swales and related drainage structures sufficient to adequately drain snowmelt, other precipitation and flooding runoff from lots and streets. Drainage capacity shall be designed for a fifty-year flood event, except that culverts for watercourses crossing streets shall be designed for a one-hundred-year flood event, and the Planning Board may require design for one-hundred-year frequency where the high damage potential or other circumstances warrant it. The rational formula or the SCS Modified Soil Complex Method shall be used, and the value of the coefficient of imperviousness shall vary according to terrain, but shall not be less than 0.30. Hydraulic design computations shall be submitted to the Board at its request. No net increase in runoff from the site is allowed.
The main street drain and the manholes centered thereon shall be located five feet from the center line of pavement; drain manholes and catch basins shall have inside diameter of four feet, and the catch basins shall have a two-and-one-half-foot deep sump below the outlet pipe invert and shall be centered one foot into the street from the curb or gutter line. The minimum pipe diameter shall be 12 inches and the grade shall be such as to provide a minimum velocity of two feet per second when flowing full and without surcharge. The distance between catch basins shall be no greater than 400 feet in order to provide proper drainage. Where water needs to be channeled or piped to or across land of others in a manner resulting in a change in intensity, subdivision approval will be predicated on the applicant first obtaining the necessary easement rights which later shall be recorded.
Adequate water supply shall be assured for each lot in a subdivision. If any boundary of a subdivision is within 1,000 feet of a municipal public water system, then each lot in that subdivision shall be connected to that water system. If said distance is greater than 1,000 feet then a separate on-lot well of adequate yield and quality may be provided. The definitive plan shall indicate the location of any public water system and fire hydrants with 2,000 feet of the subdivision. Extensions of the Town water system shall conform to the requirements of the Water Department. Water mains shall be located five feet in from the side line of the street right-of-way and five feet deep, and shall have a minimum inside diameter of eight inches. Whenever possible the water mains shall form a loop. Fire hydrants shall be located at least 18 inches into the grass plot from the curb or gutter line and shall be spaced no more than 500 feet apart, unless the Fire Chief approves in writing a different spacing. Hydrants shall be of a style approved by the Fire Chief.
Electric, telephone, cable television, fire alarm and other conduits and wiring shall be installed underground in accordance with the requirements of the source company or authority, unless the Board waives this requirement due to soil conditions or other reasons.