All subdivisions shall be designed and laid out to meet the
requirements of public safety, including precautions against possible
natural disasters, of traffic safety and convenience, of adequate
storm water drainage and sewage disposal, and with due regard for
the rights, health and welfare of the inhabitants of the Town of Swansea,
including the future residents of the proposed subdivision. Subdivision
design shall adhere to the principles of correct land use, sound planning
and good engineering.
A.
The proposed streets shall conform to any Master or Study Plan or
any part thereof adopted in whole or in part by the Planning Board.
B.
If adjoining property is not subdivided but is, in the opinion of
the planning board, suitable for ultimate development, provision shall
be required for proper projection of streets into such property by
continuing appropriate streets within the subdivision to the exterior
boundary thereof.
C.
Reserve strips prohibiting access to streets or adjoining property
shall not be permitted, except where, in the opinion of the Planning
Board, such strips will be in the public interests.
D.
Streets shall be laid out so as to intersect as nearly as possible
at right angles. NO street shall intersect any other street at less
than 60°.
E.
Street lines at all intersections shall be rounded with a curve at
each corner having a radius of not less than 25 feet. However, when
the intersection of two streets varies more than 10° from a right
angle, the radius of the curve at the acute angle may be greater than
25 feet to extent approved or required by the Planning Board.
F.
A leveling area shall be provided having a -1% grade for a distance
of 50 feet measured from the nearest exterior line of the intersecting
street, to the point of vertical curvature.
G.
Streets in a subdivision shall connect and be accessible for a public
way or a private way both of which must be deemed adequate in the
opinion of the Planning Board to provide access. If the streets in
the subdivision connect to a private way, the applicant must have
the proper rights to a private way. The Planning Board shall be satisfied
that adequate access for emergency vehicles is provided to all of
the lots within the subdivision.
H.
Three way intersections, especially within the subdivision, will
be encouraged in order to slow traffic and minimize the possibility
of collisions. Four-way intersections are to be avoided. Street jogs
shall have minimum centerline offsets from the larger classified street
as shown in table 1.
I.
Where in the opinion of the Planning Board through streets are not
needed for a safe and convenient circulation pattern, dead-end streets
may be used, but the total length of a dead-end street shall be such
as to provide minimum street frontage for not more than a total of
12 lots meeting the frontage requirements of the Swansea Zoning Bylaw.[1] The Board may waive this limitation where in the Board's
opinion greater length is justified by topography or other local conditions.
J.
All streets
shall be crowned at the centerline to prevent sheeting across the
roadway.
[Added 6-6-2022]
A.
Minor Street - A street which is used solely for access to abutting
lots, and serves as legal frontage and access to residential units.
B.
Principal Street - A street which will in the opinion of the Board
is being used or will be used as a thoroughfare between different
municipalities or will carry a heavy volume of traffic (example Route
6, 118, 103).
|
TABLE 1
STREET DESIGN STANDARDS
| |||
|---|---|---|---|
|
Minor Street
|
Principal Street
| ||
|
Maximum Cul-de-sac grade
|
4%
|
4%
| |
|
Minimum grade
|
1%
|
1%
| |
|
Minimum grade
|
9%
|
7%
| |
|
Right-of-way width
|
50'
|
60'
| |
|
Right-of-way intersection radii
|
25'
|
30'
| |
|
Street centerline offsets
|
300'
|
300'
| |
|
Centerline radii
|
150'
|
300'
| |
|
Reverse curves intermediate tangent
|
50'
|
75'
| |
|
Curve to intersection intermediate tangent
|
100'
|
100'
| |
|
Pavement width
|
26'
|
32'
| |
|
Minimum Stopping Site Distance
|
37'
|
44'
| |
|
Crest
|
200' k=28
| ||
|
Sag
|
200' k=35
| ||
|
This table is for design speed of 30 miles per hour. For higher
design speed requirements refer to the Massachusetts Department of
Public Works Highway Design Manual.
|
All dead-end streets shall be provided with a turnaround at
the closed end. Dead-end streets shall be at least 50 feet in length
before a turnaround. A dead-end street shall have a circular turnaround
at its terminus with a minimum right of way radius of 50 feet and
its minimum outside pavement radius of 40 feet.
A.
Curbing for residential minor streets shall be Cape Cod Berm. For
residential principal streets, cluster subdivisions and commercial
developments the curbing shall be granite (vertical or sloped) or
concrete (precast or cast in place).
B.
Granite (vertical) or concrete (precast) curbing with a curb inlet
shall be used as a header for all catch basins in areas where increased
flow of street water is anticipated or as required by the board.
C.
A maximum curb cut of 30 feet per lot shall be provided for a residential
driveway unless waived by the Planning Board. Curb openings for driveways
shall be graded in such a way as to prevent normal runoff water from
entering the driveway from the street right-of-way. Curb cuts shall
also be provided where sidewalks connect to the street so that wheeled
access is provided.
The area beyond the curb or sidewalk shall be graded in accordance
with the typical cross section,[1] loamed and seeded. Hydrants, lights and street signs shall
be placed at least five feet beyond the edge of the curbing so that
an obstacle-free shoulder of five feet is provided along the entire
roadway.
[1]
Editor's Note: See the cross-section diagrams included in
Attachment 1 to this chapter.
Guardrails shall be required by the Planning Board where, in
the opinion of the Planning Board, there are hazards such as drop-offs,
steep grades (greater than 50%), or water bodies beyond the shoulder.
A.
Bituminous concrete sidewalks of not less than four feet in width,
with five-foot passing zones every 200 feet, shall be constructed
on both sides of Principal Streets and Minor Streets that will be
used for commercial development.
[Amended 6-6-2022]
B.
Sidewalks shall be required on one side of the street for residential
subdivisions that contain more than 16 lots or have a roadway length
or potential length of more than 1,200 linear feet. Sidewalks will
also be required for smaller subdivisions when in the opinion of the
planning board the area is subject to a high concentration of pedestrian
travel, such as near schools, highways or business areas.
Permanent street signs with the approved street name as shown
on the Definitive Plan shall be installed at every intersection in
accordance with the Manual on Uniform Traffic Control Devices. Streets
will be labeled as "Private Way" until it has been accepted by the
Town. Any other signs required by the Planning Board, such as "Keep
Right", or "One Way" shall also be installed. Temporary street signs,
meeting the approval of the Planning Board, for material, size and
location, may be utilized until construction permits final installation.
6" x 6" Reinforced concrete or granite bounds not less than
four feet in length, shall be set on the exterior street lines at
all angle points, at the beginning and end of all curves, and at all
intersections. Such bounds shall be set with their tops flush with
the finish grade, unless the Planning Board directs otherwise.
A.
General
(1)
Storm drains, culverts, catch basins and related facilities shall
be designed to permit the unimpeded flow of all natural water courses,
to ensure adequate drainage at all low points along streets, to control
erosion, to prevent water from flowing onto abutting property and
to intercept storm water run-off along streets at intervals reasonably
related to the extent and grade of the area being drained. Lots shall
be prepared and graded consistent with drainage within the subdivision
and in such a manner that development of a lot shall not cause detrimental
drainage on another lot, on adjacent ways, and on areas outside the
subdivision.
(2)
Adequate disposal of surface water shall be provided. Catch basins
shall be built in conformity with the current specifications of the
Planning Board on both sides of the roadway on continuous grades such
that surface water will not need to run along the edge of pavement
for a distance of not more than 400 feet, at low points and sags in
the roadway, and near the corners of the roadways at intersecting
streets. Drain pipes shall be located when possible approximately
one foot from the nearer edge of the pavement and shall be laid in
straight segments with manholes at all changes in direction or grade,
at all pipe connections from catchbasins or other drains, but in no
case at an interval of more than 300 feet.
B.
Stormwater Facilities
(1)
Water collected by the drainage system shall be detained onsite and
filtered through man-made Detention and Filtration Systems before
discharge into any waterbody, wetland area, or the general environment.
Unless waived by the Planning Board, drainage water must flow for
a distance of 50 feet from the drainage system outfall pipe through
detention and filtration facilities before discharge. Detention and
filtration systems include detention basins, check swales, swales,
and other such facilities.
(2)
Every subdivision and its utilities and drainage shall be located
and designed to be consistent with the need to minimize flood damage.
(3)
Design of such detention and filtration systems shall be consistent
with the requirement that peak runoff and stream flows at the boundaries
of the development in a 100-year frequency storm shall be no higher
following development than prior to development.
(4)
All detention and filtration systems shall be designed so that the
bottom of any such facility is elevated at least two feet above the
ground water. Ground water elevation tests, as conducted by the Board
of Health for a septic system, shall be undertaken in the area of
the basin to determine such ground water elevation.
(5)
All catch basins shall be designed as vertical drains to limit water
runoff from a subdivision.
(6)
Efforts must be made to limit runoff from the site and to ensure
that relatively clean storm water is recharged into the ground water
evenly throughout the subdivision.
(7)
When vertical drains or other systems designed to introduce storm
water into the ground are utilized within 10 feet of a proposed or
existing water main, the leaching system shall be wrapped with a nonwoven
filter fabric to prevent fine materials being carried between the
washed crushed stone and surrounding materials.
(8)
Catch basins and drain pipes shall be designed to handle the runoff
for a twenty-five-year storm frequency.
(9)
Drain pipes shall be laid at a slope of not less than 1% or greater
than 10% and so as to have at least 16 inches cover to finish grade
for reinforced concrete pipes, class III and corrugated plastic pipe
(HDPE with smooth bore). With the exception of pipes used for subdrains,
storm drain pipes shall have a minimum diameter of 12 inches.
(10)
All manmade embankment areas shall be completely cleared of
organic matter. Manmade embankments shall consist of clean inorganic
fill, properly compacted with maximum side slopes of three feet horizontal
and one foot vertical then loamed (four inches minimum) and seeded
with grass. The interior side of the manmade embankments from the
bottom of the basin to its top cannot exceed six feet in height. All
embankments whether manmade or existing shall be composed of a material
which does not allow seepage. The engineer is encouraged to design
basins and embankments which utilize existing topographic features.
(11)
Adequate physical access for maintenance purposes shall be provided
in and around drainage facilities.
A.
Installation. Water mains, with hydrants, valves and other fittings,
shall be constructed and installed within the subdivision as necessary
to provide to all lots therein adequate water supply for domestic
and fire protection use. For subdivisions outside of areas where public
water supply exists, adequate water supply for fire protection, as
per the Fire Chief, shall be installed. If fire tanks are proposed,
a Homeowners Association will need to be established and tasked with
maintenance of said tanks. If sprinklers within homes are proposed,
a deed restriction shall be placed on those properties.
[Amended 6-6-2022]
B.
Connections. Proper connections shall be made with existing water
systems. Where property adjacent to the subdivision is not subdivided,
provisions shall be made for proper projections of the systems by
continuing appropriate water mains to the exterior boundaries of the
subdivision, at such size and grade as will allow for the projections,
except that the installation of water mains for these projections
will be required where their location is outside paved areas.
C.
Service connections. Service connections for water from the main
structures in the street to the exterior lines thereof shall be installed
for each lot shown on the plan, whether or not there is a building
thereon. Any deviation of this requirement necessitated by the unusual
topography or technical difficulties must have the specific approval
from the Superintendent of the Swansea Water District.
D.
Specifications. The water system shall be laid out to the satisfaction of the Planning Board and the Board of Water Commissioners who will require provision of such facilities and arrangement thereof as in their opinion are necessary to carry out the intent of Subsection A, B and C above. The installation of the water systems, including the methods of construction and the quality of materials used, shall conform to the applicable standard specifications of the Board of Water Commissioners. Water mains shall be installed on the south and west side of streets except on looped roads, where water mains shall remain on the predominant side of the street.
[Amended 6-6-2022]
E.
Testing and Chlorination. Before water is turned on in the water
supply system of a subdivision, the entire system, including pipes
and all appurtenances, shall be flushed, chlorinated and pressure
tested to the satisfaction of the Swansea Water District.
F.
System Development Charge. The attention of the subdividers and their
successors in title is drawn to the system development charge imposed
by the Swansea Water District and payable when a building service
connection is made to the water system.
Hydrants shall be installed not more than 500 feet apart and
as close to the dividing lot lines as possible. Proposed location
shall be submitted to the Fire Chief for his approval.
A.
Installation. All electrical, telephone, gas, cable television and
other utility mains including service connections shall be constructed
and installed within the subdivision as necessary to provide all lots
therein adequate supply for domestic electric, communications and
fire protection use.
B.
Specifications. Such utility systems shall be laid out to the satisfaction
of the respective utilities and the Planning Board. The installation
of these systems, including the methods of construction and the quality
of materials used, shall conform to the then current Standard Specifications
of the utilities, other applicable codes, and Laws of the Commonwealth.
C.
Street Lighting. The applicant shall ascertain the intention of the
selectmen with respect to street lighting and arrange for provision
in the preliminary planning of the utility. All costs of installation
shall be paid by the developer. Normally lights will be required at
intersections and turnarounds as a minimum.
D.
Underground Installations. All electrical, telephone, gas, cable
television and other utility mains, wires and service connections
shall be placed underground in all residential subdivisions, unless
the Planning Board determines that such placement is not feasible
or is not in the best interest of the Town of Swansea. All underground
installations shall be complete as specified prior to street paving.
E.
Service Easements. Easements for services across lots or centered
on the rear or side lot lines shall be provided where necessary and
shall be at least 20 feet wide.
