A.
Design guides. All subdivisions shall be designed
and improvements made by the developer consistent with the requirements
of this article. Design and construction shall:
(1)
Reduce, to the extent reasonably possible, the following:
(a)
Volume of cut and fill.
(b)
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%.
(c)
Number of mature trees removed.
(d)
Extent of waterways altered or relocated.
(e)
Visual prominence of man-made elements not necessary
for safety or orientation.
(f)
Volume and contamination of runoff.
[Added 8-10-2021]
B.
Required cross section. Street construction shall
conform to the required street cross section included as Exhibit A
with these rules and regulations.[1] Grass strips and driveway entrances shall be so graded
as to prevent surface water on the street from running onto private
land.
[1]
Editor's Note: Exhibit A is included at the end of this chapter.
C.
Extension. Reasonable provisions shall be made for
extension of pavements and utilities to adjoining properties, including
installation of water gates and manholes, if necessary. The developer
shall not deny others connection to the water system, drainage or
cable utilities, provided that they pay all costs of such connection
and comply with all applicable requirements of the Town of Chelmsford
or any relevant water districts.
D.
Construction standards. In the event of any question
as to construction details, specifications for the composition of
material, workmanship and the method of applying materials or in the
absence of established town standards, or if town standards are less
demanding, standards of the Massachusetts Department of Public Works
shall apply in each instance.
E.
Compliance with Zoning Bylaw.[2] The location of buildings and other structures on land
involved in subdivision or other plans submitted to the Board and
the division of such land into lots shall comply with the Town Zoning
Bylaw then in effect or with a variance granted by the Town Board
of Appeals.
F.
No expense to town. All streets, footpaths, water
mains and pipes, hydrants, fire alarm systems, drains, catch basins,
culverts and other related facilities and municipal services shall
be installed in subdivisions and completed in accordance with these
rules and regulations and without expense to the town. Water mains
and pipes (other than service pipes), hydrants and fire alarm systems
will be installed by the appropriate water district or the town at
the expense of the subdivider or will be installed by the developer
and/or subdivider at his or her expense in accordance with specifications
established by the water district and subject to its inspection, as
directed by the Planning Board. In installing the fire alarm system
within a subdivision, the developer shall connect the same to the
town's existing fire alarm system at a location designated by the
Fire Chief.
A.
Horizontal design.
(1)
Width of streets. All streets shall be designed so
as to provide safe travel for vehicles and pedestrians. Streets shown
on subdivision plans shall be classified as business streets, collector
streets, minor streets or lanes, and minimum widths shall be the following:
|
Type of Street
|
Right-of-Way
(feet)
|
Pavement
(feet)
|
|---|---|---|
|
Business street
|
60
|
34
|
|
Collector street
|
60
|
30
|
|
Minor street
|
50
|
26
|
|
Lane
|
40
|
22
|
|
Off-street path
|
8
|
Varies
|
(2)
Planned projections of streets into adjoining property.
Streets within the subdivision shall be projected to connect with
existing or proposed streets on adjoining property which come up to
the boundary line.
(a)
If adjoining property is not subdivided but
is, in the opinion of the Board, suitable for eventual development,
provision shall be made for proper projection of streets into such
property by continuing appropriate streets within the subdivision
to the exterior boundary thereof.
(b)
Streets with temporary dead ends, laid out to
permit future projection, shall conform to the provisions of alignment,
width and grade that would be applicable to such streets if extended.
(3)
Curvilinearity. Curvilinear street systems shall be
used wherever feasible.
(4)
Radii. The minimum center-line radii shall be 300
feet for business or collector streets, 150 feet for minor streets
and 100 feet for lanes.
(5)
Intersections. Street lines 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°. Wherever possible,
street intersections shall be at least 150 feet apart. Intersections
involving collector streets shall be spaced at least 400 feet apart.
Curblines at intersections shall be cut back so as to provide for
corner radii of not less than 30 feet at any intersection with a business
or collector street and of not less than 20 feet at any other intersection.
Intersections shall be located in locations that provide safe corner
sight distances. Wherever possible, the sight distance shall conform
to the following:
[Amended 9-28-1994]
|
Proposed Street
|
Intersecting Street
|
Sight Distance
(feet)
|
|---|---|---|
|
Lane
|
Lane
|
200
|
|
Any street
|
Minor, collector or business
|
300
|
(6)
Dead ends. Permanent dead-end streets (a street, extension
of a street or system of streets connected to other streets only at
a single point) shall not serve more than 10 lots unless, in the opinion
of the Board, they are necessitated by topography or other local conditions.
If dead-end streets are approved, a turnaround with a radius of at
least 62.5 feet to the outside of the layout will be required. Temporary
dead-ends shall similarly provide for a turnaround, which may be located
in part on easements over lots so long as contractual assurance is
provided that upon extension of the street the terminated turnaround
will be removed and replaced with loam and planting.
(7)
Reserve strips. Reserve strips or barriers prohibiting
access to streets or adjoining property will not be permitted.
B.
Vertical alignment.
(1)
Grades of streets. Grades of streets along the gutter
line shall be not less than 1%. Vertical curves are required wherever
the algebraic difference in grade between center-line tangents exceeds
1%. Maximum street grade and vertical curve length shall conform to
the following:
[Amended 9-28-1994]
|
Type of Street
|
Maximum Grade
|
Forward Sight Distance
(feet)
|
|---|---|---|
|
Business or collector street
|
6%
|
200
|
|
Minor street
|
10%
|
150
|
|
Lane
|
12%
|
125
|
(2)
Leveling areas. On any street where the grade exceeds
6% on the approach to an intersection, a leveling area with a slope
of not more than 4% shall be provided for a distance of at least 50
feet from the nearest edge of the intersecting traveled way. The maximum
center-line grade through a cul-de-sac shall be 5%.
[Amended 9-28-1994]
C.
Roadway construction.
(1)
Street grading. Stumps, brush, roots, boulders and
like material shall be removed as necessary for the roadway and utilities.
Wherever feasible, existing vegetation shall be retained and protected.
[Amended 7-8-1981]
(a)
The full length and width of the proposed roadway
pavement area shall be excavated or filled, as necessary, to a depth
of at least 151/2 inches below the finished surface as shown on the
profile. However, if the soil is soft and spongy or contains undesirable
material, such as clay, sand pockets, peat, stones over six inches
in diameter or any other material detrimental to the subgrade, such
material shall be removed and replaced with suitable well-compacted
material.
(b)
No topsoil suitable for reuse shall be removed
from the subdivision unless adequate topsoil will remain on site or
is otherwise assured to provide all disturbed areas within the subdivision
with a topsoil depth of at least four inches and there is also assurance
that all streets from which topsoil is being removed will be brought
to subgrade with approved materials within six months.
(2)
Finished subbase.
[Amended 7-8-1981]
(a)
Roadways shall be constructed with a foundation
of at least eight inches compacted thickness of gravel borrow conforming
to Massachusetts Department of Transportation Specification for Highways
and Bridges M1.03.0, Type b. The source of this material (with a five-pound
sample) shall be made available to the Planning Board engineer. Over
this subbase material a four-inch layer of processed gravel conforming
to the Massachusetts Department of Transportation Standard Specification
for Highways and Bridges M1.03.1 shall be placed.
[Amended 8-10-2021]
(b)
The gravel shall be spread in two layers, each
of which shall be thoroughly watered and rolled true to line and grade
with a roller of not less than 12 tons. Any depressions that appear
during and after rolling shall be filled with additional gravel and
rerolled until the surface is true and even. This surface shall be
31/2 inches below the proposed finished grade as shown on the profiles
and have transverse grade conforming to that shown on the required
cross sections.
(3)
Finished pavement.
(a)
After the treated roadway base has been subjected
to the action of traffic for a time period specified by the Planning
Board engineer, but not in excess of 30 days, a binder course of Class
I-1 bituminous concrete shall be applied and compacted and rolled
to a thickness of two inches with a true surface conforming to the
cross section of the road. A second course of Class I-1 bituminous
concrete top shall then be applied and compacted and rolled to a thickness
of 11/2 inches (two inches for business streets) with a true surface
conforming to the cross section of the road. Specifications for the
composition of material, workmanship and the method of applying pavement
material shall conform to the specifications of the town.
(b)
Pavements shall be constructed for the full
length of all streets within the subdivision shown on the plan. The
center line of such pavements shall coincide with the center line
of the street rights-of-way unless a minor variance is specifically
approved by the Board.
(c)
Minimum width of roadway pavements shall coincide with the requirements of Subsection A(1) of this section as determined by the Board.
(d)
Minimum outside diameter of roadway pavement
area within turnarounds on dead-end streets, if allowed, shall be
108 feet.
[Amended 9-28-1994; 8-10-2021]
A.
General approach. Storm drains, culverts and related
facilities shall be designed to permit the unimpeded flow of all natural
watercourses, to ensure adequate drainage at all low points along
streets, to control erosion and to intercept stormwater runoff along
streets at intervals reasonably related to the extent and grade of
the area being drained. To the maximum extent feasible, stormwater
shall be recharged rather than piped to surface water. Peak volume
and rate of runoff at the boundaries of the development must not be
higher following development than prior to development.
B.
Design basis. Storm sewers shall be based on a twenty-five-year
storm, culverts for a fifty-year storm, detention basins for a 100-year
storm with one foot of freeboard.
C.
Design method. Design shall be based on Runoff Method,
Soil Conservation Service Technical Release No. 20 (SCS TR-20). Refer
to the Chelmsford DPW Stormwater Management Regulations for more details
on design requirements. The stormwater design must meet all applicable
Massachusetts DEP Stormwater Standards. Water velocities in pipes
and gutters shall be between two feet and 10 feet per second and not
more than five feet per second on ground surfaces. All undeveloped
tributary areas shall be assumed to be fully developed in accordance
with the Zoning Bylaw. The coefficient of runoff used shall not be
less than 0.45 for subdivided areas.
D.
Storm sewers. A catch basin to manhole drain configuration
shall be used. All drain pipes shall be at least 12 inches inside
diameter and made of reinforced concrete conforming to Massachusetts
Department of Transportation specifications for Class III pipe or
such higher class as may be required by depth of cover, which shall
be not less than 24 inches, or high-density polyethylene (HDPE) pipe.
E.
Structures. Generally, catch basins will be required
on both sides of the roadway on continuous grade at intervals of not
more than 250 feet. Catch basins shall be at least six feet deep and
four feet in diameter (inside measurements), with a four-foot or greater
sump below pipe invert, and shall be constructed of precast concrete
units. Manhole covers and grates shall be in conformance with Massachusetts
Department of Transportation specifications, designed and placed so
as to cause no hazard to bicycles.
F.
Waterways. Open brooks or tributary ditches which
are to be altered shall be shaped to a cross section and gradient
and provided with stream bottom hardening, all acceptable to the Planning
Board.
G.
Connections. Proper connections shall be made with
any existing drains in adjacent streets or easements which prove adequate
to accommodate the drainage flow from the subdivision. Runoff must
be treated prior to connecting to the municipal drainage system. No
increase in volume will be allowed to the municipal drainage system.
In the absence of such facilities, or the inadequacy of the same,
it shall be the responsibility of the developer to extend drains from
the subdivision as required to properly dispose of all drainage from
said subdivision in a manner determined to be proper by the Board.
A.
The Board will not approve a subdivision plan unless
water, suitable in the opinion of the Board for domestic use and fire
protection, is certified by the developer's engineer to be available
throughout the subdivision at a minimum standard of 500 gallons per
minute open hydrant flow, with at least 20 pounds per square inch
residual pressure. In addition, the Board may require the installation
of booster pumps in dwellings to assure at least 20 pounds per square
inch pressure throughout such dwellings.
B.
In the event that a plan for a proposed subdivision
is located in an area of town which, in the opinion of the Board,
precludes the practicality of the obtainment of water supply from
any water district, the Board will not approve such subdivision unless,
in its opinion, upon advice of the Health Department, adequate groundwater
is available at the site to supply suitable water for domestic use
and, upon advice of the Fire Department, adequate provisions have
been made for firesafety. Excavations made for water connections subsequent
to paving shall be backfilled, compacted and surfaced under supervision
of the Planning Board engineer so as to completely avoid differential
settlement or displacement.
C.
Sanitary sewers.
[Added 9-28-1994; amended 4-9-1997]
(1)
Connection. The Planning Board will not approve a
subdivision plan unless all plans submitted provide for construction
of a municipal sewer system within the subdivision to be connected
to the existing municipal sewer system, if available. In the event
that the municipal sewer system is not available for reasonable connection
of the subdivision, the Sewer Commission shall provide the proponent
with a location and depth of the future connection to enable the proponent
to design and construct a dry sewer line for future use by the town.
(2)
Requirements.
(a)
All engineering plans, designs and profiles
for construction of the municipal sewer system within the subdivision
shall be prepared by the proponent and shall meet all requirements
and specifications of the Sewer Commission and shall be in general
conformity with the existing municipal sewer system.
(b)
All engineering plans, profiles and designs
shall be reviewed by the Sewer Commission and its engineer at the
proponent's expense, and a certification of approval shall be delivered
by the applicant to the Planning Board prior to approval of the definitive
subdivision plan. Failure to provide said certification shall be grounds
to disapprove the definitive plan.
(c)
The Planning Board shall not waive the provisions
of this section without the written recommendation of the Sewer Commission
that the construction of a sewer system within the subdivision is
not feasible.
(3)
Bonding.
(a)
In determining the bonding for the project pursuant
to MGL c. 41, § 81U, all costs of the sewer system, including
off-site construction, shall be included and bonded.
(b)
In the event that the location and depth of
the sewer that will be servicing the subdivision are not available,
the Planning Board may require the proponent to sufficiently bond
the cost of the sewer line installation. The proponent will bear the
cost of legal, consulting and testing fees required to arrive at an
estimate for the bond.
(4)
Sewer extension. The design and approval of the municipal
sewer within the subdivision shall fall within the sole jurisdiction
of the Sewer Commission. In the event that off-site construction is
proposed to extend the existing sewer system to service the subdivision,
the approval of the extension shall fall within the sole discretion
of the Sewer Commission. Approval of the extension shall be evidenced
by a fully executed sewer extension agreement between the proponent
and the Sewer Commission, together with all state approvals and permits.
(5)
Easements. The proponent shall provide all necessary
sewer easements required by the Sewer Commission, and these shall
be shown on the definitive plan. The final location of the sewer lines
within the subdivision and the location of the connection to the municipal
sewer shall remain in the sole jurisdiction of the Sewer Commission.
(6)
Expenses. The proponent shall be responsible for reimbursement
to the Sewer Commission of all costs and expenses incurred for legal
and engineer consultants, inspection and testing.
A.
Requirement.
[Amended 7-8-1981]
(1)
All wiring, cables and other appurtenances of electric
power, telephone and fire alarm systems shall be placed underground
within the limits of the street right-of-way, except where such underground
installations would cause undue hardship by reason of topography,
subsoil conditions or other site peculiarities. The Planning Board
may allow all or any part of the wiring, cables and other appurtenances
to be placed above ground within appropriate easements.
(2)
A plan shall be submitted for streetlighting of the
proposed subdivision from an underground electrical distribution net.
After approval by the Planning Board (fire, police and highway), the
developer shall install the lighting prior to issuance of any occupancy
permit.
B.
Timing. All cable utilities shall be installed at
the time of development.
C.
Depth. Electric power cables shall be not less than
30 inches below finished grade.
D.
Locations. Underground utilities shall be located
as indicated on the required cross section. All underground utility
systems, including power, communications and gas, shall have their
aboveground appurtenances designed to avoid system interruption or
damage in the event of flooding to base flood elevation.
A.
Where required. Footpaths shall be installed on both
sides of collector streets, on both sides of minor streets and lanes
in the RC District, based on the Chelmsford Zoning Bylaw,[1] and on one side of minor streets and lanes in other residential
districts, unless the Planning Board determines that no sidewalk is
appropriate because a continuous system is infeasible or such walk
would serve neither pedestrian convenience nor safety. Sidewalks will
be required on one side of business streets.
[Amended 9-28-1994]
(1)
In addition, the Planning Board shall, under conditions
other than the above, require that the grading of the right-of-way
be so executed as to make possible later additions of sidewalks without
major regrading.
(2)
Footpaths shall be not less than five feet in width,
except four feet on lanes, and shall be located as close as is feasible
to the street side line.
B.
Construction. All materials shall be removed for the
full width of the footpath to a subgrade 101/2 inches below the finished
grade as shown on the cross section, and all soft spots and other
undesirable material below such subgrade shall be replaced with gravel
(Massachusetts Department of Transportation Specification M1.03.0,
Type b) and rolled. The excavated area shall then be filled with gravel
(Specification M1.03.0, Type b) and rolled with a cross slope of not
less than 1/4 inch nor greater than 3/8 inch to the foot. The footpath
shall be constructed of bituminous concrete in two courses consisting
of 11/2 inches of binder and one inch of finish. All bituminous concrete
shall conform to Massachusetts Department of Transporation specifications,
as amended.
[Amended 9-28-1994; 8-10-2021]
[Amended 9-28-1994]
Easements for water mains, storm drains, utilities
and other purposes and their appurtenances shall be provided where
such are located outside the street line and shall be at least 30
feet wide. Where a subdivision is traversed by a natural watercourse,
drainageway, channel or stream, the Board may require that there be
provided an easement or drainage right-of-way of adequate width to
conform substantially to a line 15 feet distant from either side of
the watercourse or stream. The Board may require the enclosure of
any such watercourse or stream and, in the event of enclosure, may
require an adequate easement to service the same. All utility (sewer,
water, drain, etc.) pipes, structures and appurtenances shall be designed
and constructed so as to be accessible by equipment necessary for
the future operation and maintenance of the facilities.
A.
Reservation of open space. Where it believes proper
and subject to governing statutes, the Board may require the plan
to provide open areas suitably located for parks, for playground or
recreational purposes or for other required public facilities. Such
areas shall not be unreasonable in area in relation to the land being
subdivided and to the prospective public use of such land. The Board,
by appropriate endorsement on the plan, may restrict the erection
of a building or buildings upon such reserved areas for a period of
three years without its written approval. Low-impact development (LID)
features can be located within the open space.
[Amended 8-10-2021]
B.
Preservation of trees. No trees over four inches in
diameter shall be removed from a subdivision or a lot within a subdivision
and no grading of a subdivision or a lot within a subdivision shall
be undertaken until the Department of Public Works of the town has
marked those trees of such size that may or shall be removed and those
trees of such size that must be welled in order to ensure their preservation
following grading.
[Amended 10-13-1999]
C.
Shade trees. Such trees as are suitable, in the opinion
of the Board, for preservation shall be preserved. Where, in the opinion
of the Board, existing trees are inadequate, shade trees having a
diameter of at least two inches and of a variety suitable, in the
opinion of the Board, shall be planted. Such planted trees shall usually
be spaced not more than 40 feet apart, in 1/2 cubic yard of topsoil
satisfactory to the Board.
D.
Planting space. There shall be a planting space between
the curbline of the roadway and the footpath or street sidewalk. Said
area shall be surfaced with not less than six inches of topsoil, which
shall be seeded and rolled to the satisfaction of the Board. Low-impact
develoopment (LID) features can be located within the right-f-way.
[Amended 8-10-2021]
E.
Grading of slopes of streets. All slopes resulting
from grading of streets are to be graded to a slope not steeper than
2:1 in cut and 3:1 in fill nor more than 3/4:1 in ledge. Slopes and
other areas where topsoil has been removed shall be loamed with a
topsoil satisfactory to the Board to a depth of at least six inches,
seeded with a permanent grass mixture and rolled. In the event that
such slopes cannot be contained within the street side lines, the
subdivider shall reserve slope easements wherever feasible. If retaining
walls are necessary in the opinion of the Board, they shall be constructed
of reinforced concrete, stone, brick or other materials deemed suitable
by the Board.
Bounds shall be placed at all angle points,
at the beginning and end of all curves, at all intersections of streets
and at such other places as may be required by the Board. Such bounds
shall be of sound granite, not less than three feet long and not less
then five inches square. The top of each bound shall be dressed and
have a one-half-inch drill hole.
A.
At front lot corners where a road bound is not required
by the above, a granite bound not less than three feet long and not
less than three inches square, with a one-half-inch drill hole, shall
be set.
B.
No permanent bounds shall be installed until all construction
which would disturb or destroy bounds is completed.
[Amended 7-8-1981; 9-28-1994; 8-10-2021]
In some subdivisions, the Board may require
infiltration trenches (see the required cross section detail[1]) along the edge of asphalt pavement for lanes, minor streets,
collector streets and business streets. In all cases sloped granite
curbing shall be required. All granite curbing, where required, shall
be sloped granite curbing comparable to Massachusetts Department of
Transportation Specification M9.04.2, Type SB. When used on a radius
of 20 feet or less, curb shall be cut with radial joints. Workmanship
and method of setting shall conform to the specifications of the Massachusetts
Department of Transportation. Where curbing is not required, Class
I bituminous concrete berms shall be placed in accordance with Massachusetts
Department of Transportation Specification 470.
[1]
Editor's Note: See Exhibit A at the end of
this chapter.
[Amended 9-28-1994; 8-10-2021]
Guardrails or similar devices for keeping vehicles
on the road shall be installed where deemed necessary by the Board
and shall be capable of withstanding without displacement the impact
of an automobile traveling five miles per hour and of being readily
seen by drivers. Guardrails shall conform to Massachusetts Department
of Transportation specifications.
The developer shall furnish and erect street
signs at the intersection of all new streets within a subdivision
to designate the name of each street in the development, said signs
to conform with those used by the town. From the time the construction
of said street or streets is commenced until the time final approval
is requested, a temporary sign of wood or masonite with appropriate
letters may be used.
Before sale of a lot, the subdivider shall clean
up any debris thereon caused by street construction and installation
of utilities. All areas within a street destroyed or altered in construction
operations shall be restored to vegetation or other finish satisfactory
to the Board.
A.
Safety.
(1)
All precautions should be taken by the developer and
the developer's subcontractors to observe common sense safety requirements.
The Board designates the Planning Board engineer to report to the
Board all unsafe activities in preparation of the subdivision.
(2)
Holes greater than five feet in depth and soil piles
higher than 10 feet or materials stacked in an unsafe manner shall
not be allowed unless the area is adequately protected.
B.
Inspections.
(1)
Inspections shall be arranged for as outlined on Form
H, Inspection Form.[1] The Planning Board engineer may authorize minor on-site
departures from the street plan and profile and may issue a stop-work
order effective for two weeks or until the next Planning Board meeting,
whichever is sooner. No drainage or utility elements shall be backfilled
or otherwise covered until authorized by the Planning Board engineer.
[1]
Editor's Note: Form H is available from the
office of the Planning Board.
(2)
No asphalt pavement shall be placed until a certified
(by a registered professional engineer or registered land surveyor)
as-built plan has been reviewed by the Planning Board engineer.
C.
Compliance.
(1)
It is the responsibility of the developer to ensure
that the approved construction plans and these regulations are implemented.
Use of qualified persons to furnish adequate and timely engineering
supervision during construction is required. Surveillance and site
visits by town officials shall not be construed as relieving this
responsibility.
(2)
Prior to release of security, a certificate by a registered
professional engineer (civil) and a registered land surveyor acceptable
to the Board must be obtained by the developer and filed, indicating
that all improvements for which security is being released have been
completed consistent with the approved plans and with these regulations.
