B.
Design objectives. Design, including consideration of the resulting
locations of building sites, shall:
(1)
Reduce, to the extent reasonably possible, the following:
(a)
Volume of cut and fill;
(b)
Area over which existing vegetation will be distributed, 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)
Increase in peak rates of stormwater transport from the site;
(g)
Building site frontages or driveway egresses onto collector
streets;
(h)
Alteration in groundwater or surface water levels or chemical
constituents, including phosphates and nitrates;
(i)
Disturbance of important wildlife habitats, outstanding botanical
features, and scenic or historic environs;
(j)
Soil loss or instability during and after construction.
(2)
Increase, to the extent reasonably possible, the following:
C.
Construction requirements.
(1)
It is the intent that no street or way through private property
shall be accepted by the Town unless the same be previously constructed
and completed in accordance with the Standard Cross Section (see Schedules
B and C), Street Layout Plan, Profile and the following specifications.[2]
[2]
Editor's Note: Schedules B and C are included as an attachment
to this chapter.
(2)
No street, way, lot, utility or other subdivision improvement
shall be approved or constructed which is not in conformance in all
respects with all provisions of the Sharon Zoning Bylaw;[3] nor shall any such subdivision improvement be approved
or constructed which causes any existing conforming structure, lot,
use or other element to become nonconforming, nor shall any such subdivision
improvement be approved or constructed which increases the nonconformity
of any existing nonconforming structure, lot, use or other element.
(3)
No street, way, lot, utility or other subdivision improvement
shall be constructed which is not in conformance with all applicable
laws, codes, ordinances, permit requirements and regulations of the
Town of Sharon, including the Shade Tree Bylaw, the Scenic Roads Bylaw,[4] Underground Tank Bylaw,[5] Wetlands Bylaw and Sign Bylaw.[6]
(4)
No street, way, lot, utility or other subdivision improvement,
which is subject to the Massachusetts Wetlands Protection Act (MGL
c. 131, § 40), shall be constructed unless an order of conditions
has been issued by the Sharon Conservation Commission or unless a
superseding order of conditions has been issued by the Massachusetts
Department of Environmental Protection.
(5)
No street, way, lot, utility or other subdivision improvement
shall be constructed which is not in conformance with all applicable
laws, codes, ordinances, permit requirements, regulations and environmental
documentation requirements as follows:
(a)
The National Environmental Policy Act and implementing regulations
(40 CFR 1500 et seq.);
(b)
The Clean Air Act (42 U.S.C. § 7401);
(c)
The Clean Water Act;
(d)
The Resource Conservation and Recovery Act (42 U.S.C. § 3251);
(e)
The Federal Water Pollution Control Act;
(f)
Department of the Army, Corps of Engineers Section 404 (FWPCA)
Permits;
(g)
The Massachusetts Environmental Policy Act (MGL c. 30, §§ 62
through 62H) and implementing regulations (301 CMR 10.00);
(h)
The Massachusetts Department of Environmental Protection (DEP)
New Sources of Air Contaminants (Fossil Fuel) Permits;
(i)
DEP Open Burning Permits;
(j)
DEP Hazardous Waste License Program;
(k)
DEP Waste Disposal Facility Permit;
(l)
DEP Discharge to Ground Permit;
(m)
DEP National Pollution Discharge Elimination System (NPDES)
Permit;
(n)
Massachusetts Water Quality Standards;
(o)
DEP Sewer Extension or Connection Permit;
(p)
DEP Water Quality Certification Program;
(q)
DEP Subsurface Sewage Disposal Permit;
(r)
DEP Public Water System Permit;
(s)
DEP Outdoor Advertising Board Sign Permit;
(t)
Executive Office of Transportation and Construction Abandoned
Railroad Right-of-Way Consent;
(u)
DEP Superseding Order of Conditions or extension thereof;
(v)
MassDOT New Street Approach Permit;
(w)
MassDOT Brush Cutting Permit;
(x)
MassDOT Curb Cut Permit;
(y)
MassDOT Utility Line Permit;
(z)
MassDOT Sidewalk Permit;
(aa)
MassDOT Storm Drain Permit;
(bb)
MassDOT Tree Removal Permit;
(cc)
MassDOT Underground Utility Installation Permit.
(6)
Within six months of endorsement, applicant must submit a geotechnical
design report (based on borings and test pits), working drawings and
project manual, which must be approved by the Planning Board prior
to construction.
(7)
As each construction is completed, it shall be approved by the
proper Town authority and/or utility company prior to starting work
on the succeeding operation.
A.
Location and street names.
(1)
All streets in the subdivision shall be designed so that, in
the opinion of the Board, they will provide safe vehicular and pedestrian
travel and an attractive street pattern through curvilinear street
layout whenever possible, they will obtain the maximum safety and
amenity for future residents of a residential subdivision and of future
employees or visitors to a nonresidential subdivision, and they shall
be in accord with the rules and regulations of the Planning Board.
(2)
The proposed streets shall conform in location, so far as practicable,
to the Official Map, to any existing and proposed plans of the Board,
to the Master Plan or parts thereof adopted by the Board and, where
required by the Board, to the existing and proposed street system.
(3)
Provision satisfactory to the Board shall be made for the proper
projection of streets, or for access to adjoining property, whether
or not subdivided.
(4)
Reserve strips prohibiting access to streets or adjoining property
shall not be permitted, except where, in the opinion of the Board,
such strips shall be in the public interest.
(5)
Street names and walkways shall be approved by the Board to
provide names in keeping with the character of the Town. Proposed
street names shall not duplicate nor bear phonetic resemblance to
the name of existing public ways, paper streets, or any other way
qualified to afford frontage under MGL c. 41, § 81L. A proposed
street which is in alignment with an existing street shall bear the
same name as the existing street.
(6)
Subdivisions straddling municipal boundaries.
[Added 2-1-2018]
(a)
The Planning Board will not approve a subdivision of land where
a portion of the subdivision is in an adjacent municipality and sole
access to the subdivision is through Sharon.
(b)
The Planning Board will not approve a subdivision of land where
a portion of the subdivision is in an adjacent municipality and sole
access to the subdivision is through an adjacent municipality.
(c)
The Planning Board may waive applicable requirements of Subsection A(6)(a) and (b), provided that, after due consideration of the following factors, the waiver of strict compliance is in the public interest: adequate access for residents and nonresidents; adequate access for public safety, police, and fire vehicles; and equipment; burden on adjacent roadways; response time for safety, police and fire vehicles; safe access for school buses; cost to Town for services for nonresidents; adequacy of mutual aid; difficulty in cost to providing municipal services to nonresidents.
B.
Alignment.
(1)
Roadway alignment.[1]
(a)
The horizontal and vertical alignment of all segments of all
roads serving as access points to or constructed as part of the subdivision
roadways shall conform to the values given in Table 1, Roadway Alignment
(based on a 3.5-foot height of observer and a two-foot height of object).
(b)
No subdivision roadway shall cause or have the effect of creating
a nonconformity in any existing, non-subdivision street with respect
to the values and criteria set forth in Table 1, Roadway Alignment,
and, in particular, the stopping sight distance provisions set forth
in said table.
[1]
Editor's Note: See Table 1, included as an attachment to this
chapter.
(2)
Roadway alignment for sight distance. The horizontal and vertical
alignment of all segments of all subdivision roadways shall provide
adequate sight distance to provide a higher design speed should such
higher design speed be required by the Board.
(3)
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°.
(4)
Streets shall be laid out so as to intersect with adjacent streets
or adjacent subdivision land at intervals of at least 500 feet from
other subdivision or non-subdivision streets. For example, if a subdivision
street (Street A) intersects with a non-subdivision street (Street
B), the intersection of Street A and Street B must be at least 500
feet from the intersection of any other subdivision or non-subdivision
street with Street B.
(5)
The distance between curbline and property line at any intersection
shall be the same as the approach portions of the intersecting streets.
Curbline radii shall be 30 feet at an intersection involving a collector
street in the Residential District and 20 feet at all other intersections.
C.
Roadway section.[2]
(1)
Required roadway section. The roadway section shall comply with
Figure 1, Typical Roadway Section "A"; and Figure 2, Typical Roadway
Section "B"; and with Table 2, Roadway Section; and Table 3, Roadway
Materials. Nonresidential streets shall comply with standards for
collector streets in Rural Districts.
(2)
Provision of low-impact development (LID) elements as shown
in Typical Roadway Section "B" is encouraged. Porous pavement with
granular base courses as shown in Typical Roadway Section "B" may
be substituted for conventional hot mix asphalt pavement and gravel
base for sidewalks shown in Typical Roadway Section "A."
[2]
Editor's Note: See Tables 2 and 3 and the street diagrams
included as attachments to this chapter.
D.
Width.
E.
Dead-end streets.
(1)
To ensure consistency with the purpose of these regulations as enumerated in § 340-1.1, 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 be the only frontage for more than 10 potential lots under zoning applicable at the time of submittal nor shall the total length of the street, extension of a street, or system of streets exceed 1,500 feet measured from the intersection of street center lines where two distinct means of access to the Town's public street system are provided to the center of the furthest cul-de-sac for the street, extension of a street, or system of streets connected to other streets only at a single point. In determining the number of lots on a dead-end street, the enumeration of lots shall begin at the closest intersection, whether within or without the subdivision where two distinct means of access to the Town's public street system are provided.
(2)
A paved emergency access drive, walkway or bikeway (see § 340-4.3) having a maximum length of 1,000 feet in length, which in the opinion of the Board provides an adequate emergency access route for fire, police or snow-plowing equipment and contains water main connections to adjacent ways, may be considered by the Board with respect to waiver of the requirements of Subsection E(1) when it is not possible to construct a roadway that conforms to the regulations; provided, however, that the street, extension of a street, or system of streets as prescribed in Subsection E(1) shall not be the only frontage for more than 20 potential lots under zoning applicable at the time of submittal nor shall the total length of the street, extension of a street, or system of streets as prescribed in Subsection E(1) exceed 2,500 feet.
(3)
This emergency access must have a right-of-way of at least 25 feet in width that is deeded to the Town. The traveled way shall be a minimum of 18 feet in width and cannot have a grade in excess of 8%. The emergency access must connect to the street system of the Town at a point outside of the system of dead-end streets described in Subsection D(1). The water main within the paved emergency access drive, walkway, or bikeway shall connect to the water distribution system of the Town at a point outside of the system of dead-end streets described in Subsection E(1).
(4)
Dead-end streets shall be provided at the closed end with a
turnaround having an outside traveled way diameter of at least 114
feet for a minor road, unless otherwise specified by the Board (See
Schedule Q for details[4]). The turnaround or stub will be located at the property
line unless the Board approves otherwise.
[4]
Editor's Note: Schedule Q is included as an attachment to
this chapter.
(5)
There shall be a traffic island in the center having a diameter
of 25 feet and shall comply with either of the following:
(a)
Island landscaping. The traffic island shall be flush and graded
to serve as a rain garden for roadway runoff. Slopes shall not exceed
4 to 1 and the rain garden shall incorporate street trees, shrubs,
ground cover, and mulch.
(b)
Alternative island landscaping. The traffic island shall be
encircled with curb of the type used at intersection roundings for
the class of roadway and shall be attractively landscaped with street
trees, shrubs, ground cover, and mulch.
(6)
The Board may require a roadway parcel from the end of the dead-end
street to adjacent property.
(7)
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 termination
turnaround will be removed and replaced with loam and planting.
F.
Grade.
(1)
The center-line grade for any street shall not be less than
1 1/2%.
(2)
Where changes in grade exceed 0.5%, vertical curves at least
50 feet in length shall be provided.
(3)
Traveled ways shall have a cross slope at 2% or 1/4 inch per
foot.
(4)
Where curves and grades combine to create potentially dangerous
driving conditions, the Board may require a suitable amount of superelevation
of the curves or other protection.
(5)
Lot grading shall provide for on-lot treatment of runoff and
shall minimize runoff from lots to the street drainage system. Discharge
of runoff from driveways to the street drainage system is prohibited.
Lawn depressions, rain gardens, and infiltration facilities shall
be provided and shall prevent overflow onto neighboring lots or erosion
of banks.
(6)
The center-line grade of traveled ways shall not deviate from
existing ground (as defined by the Town's GIS system dated 2008) by
more than 10 feet and the average of the absolute value of the deviation
shall not be more than three feet. The applicant may, in instances
where deviations from Town topographic maps are discovered in subsequent
surveys, supply the Board with road profiles showing both the Town
topographic maps and a more accurate topographical map of the area,
provided no significant changes in topography have been made to the
area since 2008.
G.
Earthwork.
(1)
Prior to land disturbance encompassing one acre or more, the applicant shall prepare a stormwater pollution prevention plan (SWPPP) and comply with U.S. Environmental Protection Agency requirements under the National Pollutant Discharge Elimination System (NPDES) and shall obtain a stormwater certificate, issued by the Town Engineer or the Board of Selectmen as provided in the Sharon General Bylaws, Chapter 230, Article II, the Stormwater Discharges Generated by Construction Activities Bylaw.
(2)
Prior to land disturbance involving earth removal in excess of 25 cubic yards, the applicant shall obtain an earth removal permit as provided in the Sharon General Bylaws, Chapter 141, Earth Removal.
(3)
Clearing and grubbing shall comply with Section 101, Clearing
and Grubbing, of the Standard Specifications. Clearing and grubbing
shall be performed to remove all stumps, brush, roots and like material
from the area of the traveled way, berms, shoulders, sidewalks, and
utility trenches, but wherever feasible, existing vegetation shall
be protected. Cleared materials shall be removed from the property
unless otherwise approved by the Board or its agent. Appropriate erosion
control measures will be installed prior to proceeding with excavation.
(4)
Earth excavation shall comply with Section 120, Excavation Earth,
of the Standard Specifications. Excavation shall be the removal of
all materials encountered within the area of the traveled way, berms,
shoulders, and sidewalks down to the true surface of the subgrade
or to suitable material in areas where unsuitable material exists,
in preparation for foundation of roadway, sidewalks, driveways and
berms. Approved material obtained from the excavation may be used
in fills as required if, in the opinion of the Town Engineer, they
are suitable.
(5)
Embankment shall comply with Section 150, Embankment, of the Standard Specifications. When, in the opinion of the Town Engineer, suitable material is not available within the limits of the roadway location to form the subgrade or subbase, the developer shall obtain suitable additional material from other sources in accordance with this section and as may be approved by the Town Engineer. Embankments within or adjoining the right-of-way shall be evenly graded and pitched at a slope of not greater than four horizontal to one vertical, or two to one with a retaining wall. Where cuts are made in ledge, other slopes may be determined with the approval of the Town Engineer. Where terrain necessitates greater slopes, retaining walls, terracing, fencing, or rip-rap may be used, either alone or in combination, to provide safety and freedom from maintenance, but must be done in accordance with plans filed with and approved by the Planning Board. Retaining walls shall normally be constructed of stone, with wall thickness at any point not less than 1/3 the depth below retained grade, or in accordance with MassDOT requirements. Whenever embankments are built in such a way as to require approval by the Board, the developer must furnish to the Town duly recorded access easements free of encumbrances for maintenance of the slopes, terraces or retaining walls. All such slopes shall be grassed or planted in accordance with § 340-4.6E.
(6)
Grading shall comply with Section 170, Grading, of the Standard
Specifications. The subgrade surface, 16 inches below the finished
surface grade in minor and secondary streets, and 18 inches below
the finished surface grade in all streets in nonresidential subdivisions,
shall be prepared true to the lines, grades and cross-sections given
and properly rolled. If existing soils on new roads are not suitable
for use as a roadway subgrade (such as peat and clay), the soils will
either have to be removed and replaced with a compacted gravel or
reinforced with a suitable geotextile reinforcement, as per the Town
Engineer.
(7)
Gravel subbase shall comply with Section 401, Gravel Sub-Base,
of the Standard Specifications. Gravel subbase or foundation shall
contain no stones having any dimensions greater than three inches,
shall be spread in two equal layers on the surface of the subgrade
to a minimum depth of 12 inches in conformity with requirements of
Section ML.030, Type B, of the Massachusetts Department of Public
Works Standard Specifications for Roadways and Bridges, 1992 Edition,
or as currently amended. Each layer shall be thoroughly watered, rolled
and compacted true to line and grade. Any depressions that appear
during and after the rolling shall be filled with additional gravel
and rerolled until the surface is true. Mirafi, Supac or other subgrade
stabilizing geotextile may be required by the Town Engineer prior
to gravel placement.
(a)
Subbase. Gravel subbase shall be newly excavated gravel from
approved borrow sources complying with Section 401, Gravel Subbase,
of the Standard Specifications.
(b)
Recycled subbase. The Board strongly encourages use of reclaimed
and recycled materials in subdivision construction. Reclaimed pavement
borrow material for subbase shall conform to Section 404, Reclaimed
Pavement Borrow Material, of the Standard Specifications.
(8)
Final grading, rolling and finishing, including the shaping,
trimming, rolling and finishing of the surface of the subbase prior
to application of gravel for surfacing of the traveled way and base
courses for walks and berms, shall be in accordance with this section
and as directed by the Town Engineer. Each layer shall be compacted
to not less than 95% of the maximum dry density of the material, as
provided in the Standard Specifications. The rolled gravel shall be
tested for compaction. All such tests shall be made at the expense
of the developer, when requested by the Town Engineer.
H.
Pavement.
(1)
Pavement for traveled ways shall be hot mix asphalt pavement
(HMA) in compliance with the Standard Specifications.
(2)
The minimum thickness of compacted hot mix asphalt pavement
shall comply with the materials and thicknesses shown in Table 3,
Roadway Materials.[5] The binder course of pavement shall be laid in one course
on minor streets and lanes in residential subdivisions and shall be
laid in two courses on collector streets in residential subdivisions
and on all nonresidential subdivision streets. The Town Engineer may
require the installation of a geosynthetic material over any areas
in the subbase pavement that, in his opinion, require reinforcement
prior to the placement of an additional course of pavement.
[5]
Editor's Note: Table 3 is included as an attachment to this
chapter.
(3)
Pavement for traveled ways in subdivisions shall be hot mix
asphalt pavement. The material and construction methods for laying
pavement shall conform in every way to the applicable sections of
Section 460 of the Standard Specifications. No pavement installation
is permitted before March 31 of any year nor after December 1 of any
year without written permission of the Town Engineer. Paving will
not be allowed if it is raining or the roadway is wet, if frost is
present, or when the air temperature is below 40° F. Trucks transporting
the mixture shall be covered and insulated as required. The temperature
of the hot mix asphalt mixture, within a tolerance of plus or minus
15° F., when delivered at the project is governed by the temperature
of the base upon which the mix is placed and the compacted thickness
of the course of pavement as set forth below:
|
Base Temperature on Which Mix is Placed
(in ° F.)
|
1 1/2" Thick
|
2" Thick
| |
|---|---|---|---|
|
35° to 40°
|
305
|
295
| |
|
40° to 50°
|
300
|
285
| |
|
50° to 60°
|
295
|
280
| |
|
60° to 70°
|
285
|
275
| |
|
70° to 80°
|
280
|
270
| |
|
80° to 90°
|
270
|
265
| |
|
90° +
|
265
|
260
|
(4)
All traveled ways will be prepared in such a manner that all
manholes, catch basins, gate valves or other structures are installed
with bituminous paving around the perimeter of each structure, so
that a smooth transition is maintained between the top of each structure
and the road surface.
I.
Street requirements.
(1)
Curb and berm.
(a)
Curb or berm shall be placed along both sides of traveled ways.
Hot mix asphalt monoberm shall be installed along both sides of all
streets except where vertical granite curb is required and where curb
may be eliminated along drainage swales as set forth herein.
(b)
Granite curbing Type VA4 with six-inch reveal is required at
intersections as per MassDOT M9.04.1B. Vertical granite curbing shall
include curb return radius curb, one six-foot-long straight curb section,
and a transition curb at each location. Vertical granite curb shall
be installed on the straight leg of T intersections and shall extend
for the same length as the granite curb on the opposite side of the
street. Vertical granite curbing shall be placed after the binder
course and before the finish course of hot mix asphalt. See Schedule
N.[6]
[6]
Editor's Note: Schedule N is included as an attachment to
this chapter.
(c)
Alternative edge of traveled way. Curbing shall be omitted along
roadway segments or along entire roadways to allow stormwater runoff
to flow into dry swales. Where a rain garden is proposed, curbing
shall be omitted around cul-de-sac islands to allow stormwater runoff
to flow into a cul-de-sac rain garden.
(2)
Curb cuts.
(a)
Driveways in subdivisions containing one- and/or two-family
dwellings only shall be at least 10 feet wide and shall have an opening
of at least 16 feet at the gutter line.
(b)
Driveways for multiple dwellings and all nonresidential uses
shall be at least 16 feet wide and shall have an opening of at least
20 feet at the gutter line.
(c)
Where rolled curbs are to be used, the driveway flare should
have a three-foot radius. Driveway cuts shall not be within 65 feet
of the intersection of the center line of intersecting streets.
(e)
At every curb step down there shall be a ramp three feet wide
adjacent to the granite curb sections. See Schedule D. All ramps must
meet Massachusetts Architectural Access Board requirements regarding
slope, dimensions and locations. See Schedules D and O.[8]
[8]
Editor's Note: Schedules D and O are included as an attachment
to this chapter.
(f)
All driveways shall be constructed to provide adequate access
of all emergency vehicles as determined by the Town Engineer and the
Fire Chief.
(g)
Driveways shall be graded to drain away from the right-of-way
or on-lot drainage structures provided such that no runoff from driveways
is discharged to the right-of-way.
(3)
Guard rails. Guard rails shall be required whenever the slope
is greater than four horizontal to one vertical downhill, and the
length of the slope is determined by the Board or Town Engineer to
constitute a hazardous condition or there is a drop of more than four
feet from the traveled way to the bottom of slope. Guard rails shall
comply with current MassDOT Standard Details. An acceptable guard
rail is shown in Schedule P.[9] An applicant shall always check MassDOT standards to verify
the latest approved guard rail.
[9]
Editor's Note: Schedule P is included as an attachment to
this chapter.
(4)
Private road covenant. As a condition for approval of a subdivision
plan, the Board will require the owner to enter into a declaration
of property restrictions and covenants concerning the maintenance
of private roadways servicing the subdivision, drainage overflow depressions
serving more than one lot of the subdivision and other requirements
which affect more than one lot of the subdivision or which are intended
to remain in force permanently or for an extended period of time.
A model Declaration of Property Restrictions and Covenants is appended
hereto as Form H-1. Said form may be modified in order to meet the
particular characteristics or features of the subdivision plan.
J.
Subdivision access.
(1)
Primary access route. Streets within a subdivision shall be
deemed to provide adequate access to the lots they serve only if streets
outside the subdivision which serve as the primary access route between
the subdivision entrance and the general roadway system of the Town
comply with the standards established hereinafter. The street or system
of streets comprising the primary access route extending from the
subdivision entrance to the nearest intersection of two through streets,
each of which provides access to the general street system of the
Town, must provide adequate access for the subdivision. The segment
of the primary access route measured from the subdivision entrance
that is required to conform to the standards set forth herein shall
not exceed a distance of 50 feet for each lot within the subdivision.
The segment of the primary access route that is required to conform
to the standards set forth herein shall be brought into compliance
prior to release of any lots in the subdivision.
(2)
Required standards.
(a)
For ways providing access to a subdivision of not more than
12 dwelling units, the primary access route shall provide a traveled
way having a width that complies with requirements for a lane.
(b)
For ways providing access to a subdivision of more than 12 dwelling
units, the primary access route shall provide a traveled way, one
planting strip, and one sidewalk having widths that comply with requirements
for a minor street.
A.
Locations.
(1)
Sidewalks.
(a)
Sidewalks shall be provided within the street right-of-way as
follows:
(b)
Sidewalks shall have minimum widths as shown in Table 2, Roadway
Section,[1] and shall extend the full length of the street and completely
around the cul-de-sac. One sidewalk is required along street segments
that are contiguous to the subdivision and contiguous to lots that
include land in common ownership with land in the subdivision at any
time within five years prior to submission of the definitive plan.
[1]
Editor's Note: Table 2 is included as an attachment to this
chapter.
(2)
Bikeways. The Planning Board encourages the provision of bikeways
within subdivisions. Bikeways may be provided within the right-of-way
in lieu of constructing one of two required sidewalks. To accommodate
the shared bikeway, the traveled way may be offset from the center
of the right-of-way and other cross-section elements adjusted. Bikeways
are particularly important for roadways having substantial continuity.
Bikeways shall have a minimum width of 10 feet.
(3)
Shared pathways. The Planning Board encourages the provision
of shared pathways within subdivisions. One shared pathway may be
provided within the right-of-way as shown in Typical Roadway Section
"B" in lieu of constructing both required sidewalks.[2] Shared pathways are particularly important for roadways
having substantial continuity. Shared pathways shall have minimum
widths as shown in Table 2, Roadway Section,[3] and provision of a twelve-foot width is desirable.
(4)
Separate right-of-way facilities. Walkways, bikeways, and shared
pathways on separate rights-of-way may be required by the Board to
provide circulation, to link to other facilities providing routes
of substantial continuity, or access to schools, playgrounds, parks,
shopping, transportation, open space, or community facilities, or
for such other reasons as the Board may determine.
(5)
Pavement for sidewalks, bikeways, and shared pathways shall
be hot mix asphalt pavement or porous asphalt pavement.
(b)
Porous asphalt pavement shall consist of hot mix asphalt pavement
over a chocker course over a filter course, over a filter blanket
course over a reservoir course. Thickness shall comply with Table
3, Roadway Materials. The chocker course, filter course, filter blanket,
and reservoir course shall be wrapped on the sides and bottom with
nonwoven filter fabric. The reservoir course shall be provided with
a four-inch-minimum-diameter PVC underdrain installed with a minimum
clearance of two inches between the crown of the pipe and the top
of the reservoir course. Porous asphalt pavement may be substituted
for conventional hot mix asphalt with gravel base for any sidewalk
shown in Typical Roadway Section "A."[5]
[5]
Editor's Note: The typical roadway section diagrams are included
as an attachment to this chapter.
(c)
In driveway areas and driveway apron areas, the thickness of
the binder course of hot mix asphalt pavement shall be increased by
one inch and the thickness of porous pavement shall be increased by
one inch.
(d)
A 1.5% cross-slope shall be maintained for drainage.
B.
Alignment.
(2)
Off-street walkways shall have minimum center-line radius of
25 feet. Off-street bikeways and shared pathways shall use a design
speed of 20 miles per hour. The maximum gradient of off-street walkways,
bikeways, and shared pathways shall be 8% for segments of 100 feet
or less. Leveling areas at intersections with sidewalks shall be shown
in detail.
C.
Planting strips and slopes.
(1)
The planting area between the sidewalk and the street pavement
shall be planted with six-inch-thick loam and sod where the street
serves as frontage for a lot. Where no buildable lot exists, the Town
Engineer may allow a substitution of six-inch-thick loam and seed
or a six-inch-thick layer of durable mulch.
(2)
Embankments, cut slopes, grading strips, and tree easement areas
shall be provided with a four-inch-thick layer of plantable soil borrow
and seed. Tree easement areas shall have a maximum cross slope of
4% unless fieldstone walls are provided around trees providing a level
area to foster vertical growth habit. The maximum slope for embankments
and earth cut slopes shall be three horizontal to one vertical. Ledge
slopes shall be established based upon stability calculations provided
by the design engineer and shall have a minimum batter of four vertical
to one horizontal.
A.
General.
(1)
All required utilities, exclusive of transformers, shall be
placed underground at the time of initial construction. Required utilities
may include water, storm drain, telephone, electricity, gas, street
lighting, fire alarm systems and cable television unless otherwise
specified by the Board. Locations for transformers and other utility
boxes must be at property sideline boundaries, unless otherwise approved
by the Town Engineer.
(2)
Where adjacent property is not subdivided or where all the property
of the applicant is not being subdivided at the same time, provision
shall be made for the extension of the utility system by continuing
the mains the full length of streets and to the exterior limits of
the subdivision at such grade and size which will, in the opinion
of the Board, permit their proper extension at a later date.
(3)
Connections for drain, water, gas, electric, telephone, and
cable services from the main utility structure or utility line in
the right-of-way to the exterior line of the right-of-way shall be
constructed for each lot, whether or not there is a building thereon,
except that the Board may waive such requirement, in whole or in part,
in the case of a lot to be used for a park, playground or for any
other purpose for which, in the opinion of the Board, such connections
shall not be required.
(4)
Installation and materials, unless otherwise specified, shall
conform to the standards of the Town of Sharon, to utility company
standards, and to applicable codes.
(5)
Excavation for structures shall comply with Section 140, Excavation
for Structures, of the Standard Specifications. Excavation for structures,
including foundations for drains and water pipes, walls and other
structures, shall be made to the depth as indicated on the definitive
plan or established by the Town Engineer as appropriate. Rock excavation
designated as Class B encountered in trench excavation shall be removed
as directed by the Town Engineer.
(6)
Drainage shall comply with Section 200, Drainage, of the Standard
Specifications. All drain, gas and water pipes, underground utilities,
and other structures shall be installed to the right-of-way line upon
the completion of roadway subgrade and before the placing of the subbase,
gravel base course, sidewalks or pavement. If the pavement is removed,
excavated or damaged, the trench shall be covered with a poured reinforced
concrete slab to the lines, grades and dimensions approved by the
Town Engineer.
B.
Water system.
(1)
Every subdivision shall be connected to the public water system
by the developer, unless otherwise approved by the Planning Board
and the Board of Health. Where connection to the public system is
not feasible, a subdivision plan shall be approved only upon presentation
of evidence satisfactory to the Board, upon advice of the Board of
Health, that adequate and suitable supply of potable water is available,
and upon evidence satisfactory to the Board, upon advice of the Fire
Chief, that adequate provisions for fire fighting have been made.
(2)
Water pipes and related equipment, such as hydrants and main
shutoff valves, corporation shutoff valves, service pipe to curb boxes,
curb boxes and blowoffs, shall be installed within every subdivision
as necessary to provide all lots on each street with adequate water
supply for domestic and fire protection use. Such system shall be
installed regardless of whether it is to be connected to a public
system or private on-site systems are to be initially relied upon.
Dead-end water mains exceeding 500 feet in length are not permitted.
The parallel mains of any loop shall be no closer than 200 feet.
(3)
Public water mains, house connections, and related facilities
shall be installed to the standards of the Department of Public Works.
Mains shall be Class 52 cement-lined ductile iron pipe and shall not
be less than eight inches in diameter unless approved by the Planning
Board in conjunction with the Town of Sharon Public Works Department,
Water Division. Pipe joints shall be gasketed push-on type.
(4)
Where public water is provided, hydrants shall be provided every
500 feet or part thereof on one side of each street unless a greater
distance is approved by the Chief of the Fire Department in writing.
In any case, there shall be a minimum of one hydrant in each subdivision.
They shall be of a style approved by the Department of Public Works.
The Town of Sharon uses Mueller Super Centurion, open right hydrants,
or American Darling B62B, open right hydrants. The deliverable fire
flow shall meet current ISO requirements for all existing/potential
structures served. Minimum flow requirements at all locations shall
be 500 gallons per minute (gpm) with a residual pressure of 20 pounds
per square inch (psi). The table below shows required flow pressure
for different building separation distances. Flow calculations shall
be submitted based upon combined fire flow and peak domestic use and
current, site-specific flow tests. All curb stops must open left.
Water meter, water service and curb stop requirements shall conform
to Sharon Water Department standards. For residential areas with one-
and two-family dwellings, required fire flows are as follows:
|
Distance Between Buildings
(feet)
|
Required Fire Flow
(gpm)
|
Residual Pressure Needed
(psi)
| |
|---|---|---|---|
|
More than 100
|
500
|
20
| |
|
31 to 100
|
750
|
20
| |
|
11 to 30
|
1,000
|
20
| |
|
10 or less
|
1,500
|
20
|
(5)
Each hydrant shall be served directly from the water main through
a six-inch lateral connection. It shall be gated with a 5 1/4-inch
bottom value and shall have 2 1/2-inch hose outlets and a 4 1/2-inch
pump outlet. Hydrants shall open to the right. Water main gate valves
shall be located in such number and locations that lines by individual
block may be isolated for maintenance purposes, and should open to
the left. Hydrant gates shall be located within the paved traveled
way surface.
(6)
The entire system shall be pressure tested and disinfected in
accordance with American Waterworks Association Standards (AWWA) and
approved by the Department of Public Works prior to acceptance.
C.
Electricity and other cables. Wiring for the telephone, electricity,
street lighting system and cable television shall be installed underground
in conduit as shown in Figures 1 and 2[2] with vertical and/or horizontal separation as approved
by the Town Engineer. Service shall be provided to each lot and each
street light before the subgrade is prepared. All in-ground wiring
shall be placed in PVC conduit. The Board may permit transformers,
switches and other such equipment to be placed on the ground in approved
locations, screened from view with evergreen shrubbery. All utility
boxes shall be placed at property side lines; exceptions must be approved
by the Town Engineer.
[2]
Editor's Note: Figures 1 and 2 are included as an attachment
to this chapter.
D.
Street lighting system.
(1)
A street lighting system shall be supplied, installed and operated
by the developer until such time as the system is accepted by the
Town. The street lighting system shall be designed by a registered
professional electrical engineer. The layout and design of the system
shall be incorporated in the submission of the definitive plan. No
lot releases will be approved until lights are operational. All lights
must be protected with barricades of some type during construction,
in order to prevent damage to the lighting.
(2)
Fixtures and lamps. Streets and sidewalks shall be illuminated
by pedestrian-scale spherical lanterns with the specifications listed
hereunder. The following specifications apply only to lanes and minor
streets and sidewalks in residential subdivisions. Collector streets
and nonresidential subdivision streets shall be supplied with standard
NSTAR Electric LED "cobra" type street lights.
(a)
The lamp shall be 35 watt, 120 volt high-pressure sodium. Ballast
shall be 35 watt 120 volt c.w.a linear case mounted in pole. Lampholder
shall be medium base porcelain.
(b)
The globe shall be 16 inches in diameter clear, smooth, seamless
polycarbonate; refractor shall be borosilicate glass; fitter shall
be cast aluminum twist lock.
(c)
Pole shall be ten-foot-high round straight aluminum 4.5-inch
diameter x 0.125 inch wall. Base shall be two-piece cast aluminum
nine-inch diameter X four inches high. Anchorage shall consist of
4 5/8-inch by sixteen-inch by two-inch galvanized steel anchor
bolts on a seven-inch bolt circle.
(d)
Base to be poured concrete 12 inches by 12 inches by 24 feet
deep.
(e)
The luminaire shall be finished with factory-applied tropic
black baked acrylic enamel. The pole shall be anodic coffee black.
(3)
Layout.
(a)
Lights on one side of the street shall be located in front of
each proposed lot. The light should not be closer than 15 feet to
each anticipated driveway location and two feet in back of the curb
in the grass strip.
(b)
Additional lights shall be positioned so that the maximum distance
between lights is 150 feet.
(c)
In addition, a light shall be placed on each side of the street
at the point where a new street intersects an existing street at the
entrance to a new subdivision.
(d)
Hand holes shall be positioned at an interval of one per every
other light in the grass strip.
(4)
Conduit and wiring.
(a)
All wiring for street lighting shall be installed in conduit
located under the grass strips unless approved otherwise by the Town
Engineer.
(b)
Sheath in appropriate PVC conduit except within one foot of
finished grade. Aluminum conduit shall be used within one foot of
finished grade to resist damage from impact.
(5)
Controller cabinet.
(a)
The control cabinet shall be constructed of cast aluminum and
contain a hinged, gasketed, weatherproof cast aluminum door with a
conventional police lock and key. Two keys shall be furnished.
(b)
The cabinet shall have a photocell-activated on/off control.
(c)
The cabinet shall be mounted on a concrete base.
(e)
Meter socket and meter shall be mounted externally as required
by NSTAR Electric and Gas.
(f)
The cabinet shall be approximately four feet high by two feet
six inches wide by one foot six inches deep. Cabinet color shall be
dark green.
(g)
Cabinet shall be Crouse Hinds CAC Series or equal.
(6)
Installation, ownership and operation.
(a)
The developer shall purchase and install an approved street
lighting system. Prior to the occupancy of any dwelling, the complete
lighting system shall be operated and maintained by the developer
at the developer's expense daily from dusk to dawn, and such operation
will include all light fixtures from the access to an existing public
way to the furthest occupied dwelling.
(b)
The installation shall conform to the applicable provisions
of the Massachusetts Electric Code, and as required by NSTAR Electric
Company and the Town of Sharon. Power shall be supplied through a
meter furnished and installed by NSTAR Electric Company.
(c)
Properly operating fixtures shall become the property of the
Town of Sharon upon street acceptance.
(d)
The developer shall purchase extra light fixture(s) to be turned
over to the Town of Sharon prior to street acceptance. The quantity
of extra (spare) fixtures shall be 5% of the total number of fixtures
installed, rounded up to the nearest integer, with a minimum of one
for any subdivision.
E.
Gas.
(1)
Gas mains shall be installed if a connection to the gas distribution
system is available.
(2)
The Columbia Gas Company shall be notified by the developer
upon approval of the definitive plan so that installation of gas mains
may be completed without undue delay. If excavation is made after
the subgrade is completed and inspected, the mains shall be put in
a trench covered with a poured reinforced concrete slab to the lines,
grades and dimensions approved by the Town Engineer.
A.
General. The stormwater management system shall collect, convey,
treat, and recharge stormwater in a manner which will ensure protection
of property, preservation of water resources, minimization of environmental
impacts, and protection of public and environmental health by providing
adequate protection against pollution, flooding, siltation and other
problems caused by poor drainage. The stormwater management system
shall comply with the following:
(1)
Adhere to standard engineering practice.
(3)
Conform to the current edition of the Massachusetts Department
of Environmental Protection's Massachusetts Stormwater Handbook.
(4)
Maintain pre-development drainage patterns and pre-development
hydrological conditions in groundwater and surface waters as nearly
as possible.
(5)
Include a strategy for source control and best management practices
(BMPs).
(6)
Recharge runoff from pervious surfaces.
(7)
Recharge roof water in separate facilities.
(8)
Provide treatment train for the water quality volume that reduces
the contaminant burden in stormwater to the maximum extent possible
(MEP) using best management practices (BMPs).
(9)
Maintain or enhance surface water quality and groundwater quality.
(10)
Protect or enhance resource areas subject to regulation under
the Massachusetts Wetlands Protection Act (MGL c. 131, § 40)
(WPA).
(11)
Utilize low-impact design that manages stormwater close to the
source where practicable.
(12)
Disconnect runoff from lots from the subdivision's closed storm
drain system.
(13)
Collect and convey surface water for applicable design storms.
(14)
Avoid any increase in the peak rate or volume of stormwater
discharge at the property boundary for each storm event specified
hereinafter.
(15)
Include stormwater BMPs that abate phosphorous levels in accordance
with the Massachusetts Stormwater Handbook.
(16)
Implement an operation and maintenance (O&M) plan that complies
with DEP guidelines and ensures proper function of the stormwater
management system and provides an acceptable future maintenance burden.
(17)
Provide a sufficient level of health and environmental protection
during construction.
B.
Submissions. Design of the stormwater management system shall be
prepared by a Massachusetts registered professional engineer, and
all submitted plans, calculations, and reports shall bear the engineer's
signature and seal. Deep hole observations shall be conducted under
the direction of a Massachusetts licensed soil evaluator. Submissions
shall comply with the minimum content requirements as set forth hereinafter:
(1)
Plans, profiles, and sections conforming to the requirements
of these rules and regulations showing the stormwater management system
and existing and proposed buildings, surface grades, surface treatments,
and utilities.
(2)
A stormwater management report including calculations and a
detailed narrative describing pre-development and post-development
conditions, the design and function of the stormwater management system,
and the procedures and methods used for analysis.
(3)
Pre-development and post-development watershed plans showing
existing and proposed buildings, surface grades, surface treatments,
catch basins and culverts, watercourses, watershed and catchment boundaries,
flow lines, Natural Resources Conservation Service (NRCS) soil boundaries
and hydrologic soil groups.
(4)
Pipe flow calculations based upon the Rational Formula providing
pipe diameter, inverts, slope, velocity (flowing full), length, capacity,
design flow, and v/c ratio.
(5)
Stormwater basin design calculations shall be provided based
upon TR-20.
(6)
Logs of soil borings or deep observation holes.
(7)
Soil permeability test data.
(8)
Groundwater monitoring data.
(9)
Plans showing the limits of all "resource areas" subject to
regulation under the WPA based upon a field survey of points established
pursuant to an order of resource area delineation or an order of conditions
issued within two years of the date of submission.
(10)
An operation and maintenance plan.
(11)
Organization documents for the party responsible for operation
and maintenance of the stormwater management system which shall include
details of the mechanism used to provide funding in perpetuity.
C.
Standards. The stormwater management system shall comply with the
standards set forth hereinafter (and more fully defined in the current
version of the Massachusetts Stormwater Handbook).
(1)
Standard 1. No new stormwater conveyances (e.g., outfalls) may
discharge untreated stormwater directly to or cause erosion in wetlands
or waters of the Town of Sharon.
(2)
Standard 2. Stormwater management systems shall be designed
so that post-development peak discharge rates do not exceed pre-development
peak discharge rates.
(3)
Standard 3. Loss of annual recharge to groundwater shall be
eliminated or minimized through the use of infiltration measures,
including environmentally sensitive site design, low-impact development
techniques, stormwater best management practices and good operation
and maintenance. At a minimum, the annual recharge from the post-development
site shall approximate the annual recharge from the pre-development
conditions based on soil type. This standard is met when the stormwater
management system is designed to infiltrate the required recharge
volume as determined in accordance with the Massachusetts Stormwater
Handbook.
(4)
Standard 4. Stormwater management systems shall be designed
to remove 80% of the average annual post-construction load of total
suspended solids (TSS). This standard is met when:
(a)
Suitable practices for source control and pollution prevention are
identified in a long-term pollution prevention plan and thereafter
are implemented and maintained;
(b)
Structural stormwater best management practices are sized to capture
the required water quality volume determined in accordance with the
Massachusetts Stormwater Handbook; and
(c)
Pretreatment is provided in accordance with the Massachusetts Stormwater
Handbook.
(5)
Standard 5. For land uses with higher potential pollutant loads,
source control and pollution prevention shall be implemented in accordance
with the Massachusetts Stormwater Handbook to eliminate or reduce
the discharge of stormwater runoff from such land uses to the maximum
extent practicable. If, through source control and/or pollution prevention,
all land uses with higher potential pollutant loads cannot be completely
protected from exposure to rain, snow, snow melt and stormwater runoff,
the proponent shall use the specific structural stormwater BMPs as
provided in the Massachusetts Stormwater Handbook. Stormwater discharges
from land uses with higher potential pollutant loads shall also comply
with the requirements of the Massachusetts Clean Waters Act, MGL c.
21, §§ 26 through 53, and the regulations promulgated
thereunder at 314 CMR 3.00, 314 CMR 4.00 and 314 CMR 5.00.
(6)
Standard 6. Stormwater discharges within the Zone II or Interim
Wellhead Protection Area of a public water supply and stormwater discharges
near or to any other critical area require the use of the specific
source control and pollution prevention measures and the specific
structural stormwater best management practices determined by the
Department to be suitable for managing discharges to such area as
provided in the Massachusetts Stormwater Handbook. A discharge is
near a critical area if there is a strong likelihood of a significant
impact occurring to said area, taking into account site-specific factors.
Stormwater discharges to outstanding resource waters and special resource
waters shall be removed and set back from the receiving water or wetland
and receive the highest and best practical method of treatment. A
"stormwater discharge" as defined in 314 CMR 3.04(2)(a)1 or (b) to
an outstanding resource water or special resource water shall comply
with 314 CMR 3.00 and 314 CMR 4.00. Stormwater discharges to a Zone
I or Zone A are prohibited, unless essential to the operation of the
public water supply.
(7)
Standard 7. A redevelopment project is required to meet the
following stormwater management standards only to the maximum extent
practicable: Standard 2, Standard 3, and the pretreatment and structural
stormwater best management practice requirements of Standards 4, 5
and 6. Existing stormwater discharges shall comply with Standard 1
only to the maximum extent practicable. A redevelopment project shall
also comply with all other requirements of the stormwater management
standards and improve existing conditions.
(8)
Standard 8. A plan to control construction-related impacts,
including erosion, sedimentation and other pollutant sources, during
construction and land disturbance activities (construction period
erosion, sedimentation and pollution prevention plan) shall be developed
and implemented.
(9)
Standard 9. A long-term operation and maintenance plan shall
be developed and implemented to ensure that the stormwater management
system functions as designed.
(10)
Standard 10. All illicit discharges to the stormwater management
system are prohibited.
D.
Geotechnical testing.
(1)
Soil borings logs shall be provided to classify soils within
proposed surface stormwater basins and subsurface absorption systems
and throughout the drainage study area. Boring logs shall be provided
within surface stormwater basins and subsurface absorption systems;
a minimum of one soil boring shall be provided for each 5,000 square
feet of basin area or a minimum of two soil logs per basin, whichever
is greater. One boring shall extend to a depth of 20 feet below existing
grade or to impervious strata or to refusal, whichever is shallower.
The other boring shall extend to the elevation of the design bottom
elevation of the basin and shall be used to perform a borehole permeability
test. Additional soil boring logs shall be provided to classify soils
throughout the drainage study area, particularly in locations where
available National Resource Conservation Service mapping is indeterminate
or classifies soils as Udorthents.
(2)
In-situ field bore hole permeability test data shall be provided
within surface stormwater basins and subsurface absorption systems;
a minimum of one permeability test shall be provided for each location.
For larger surface stormwater basins and subsurface absorption systems,
additional permeability tests may be required as determined by the
Board. Permeability testing shall be witnessed by the Board of Health
Agent or the Planning Board agent. If permeability testing is desired
to be performed in soils of low permeability, laboratory tests for
hydraulic conductivity shall be performed on undisturbed samples by
the Falling Head Permeability Test using flexible membrane triaxial
test cells with back pressure (U.S. Army Corps of Engineers Engineering
Manual EM 1110-2-1906, Appendix VII).
(3)
A minimum of one monitoring well shall be installed within each
stormwater basin. Monitoring wells shall extend to a depth of 10 feet
below existing grade or four feet below the design elevation of the
bottom of the stormwater basin, whichever is deeper.
(4)
The elevation of groundwater shall be recorded by a Massachusetts
licensed soil evaluator, professional engineer, or professional land
surveyor once in each of four months. When observations are taken
during the months of May through December, the design groundwater
elevation shall be adjusted to reflect spring high groundwater conditions
using the Frimpter Method.
E.
Hydrologic analysis.
(1)
The drainage study area shall encompass the project site and
all tributary upgradient areas. The boundary of the drainage study
area and the analysis points shall be the same for the pre-development
condition and the post-development condition. Pre-development and
post-development plans of the drainage study area shall show existing
and proposed buildings, paved areas, and surface treatment for all
open areas. The plans shall show existing and proposed elevations
based upon one-foot contour intervals. The plans shall show existing
and proposed catch basins and culverts, watercourses, watershed and
catchment boundaries, and flow lines, Natural Resources Conservation
Service (NRCS) soil boundaries and hydrologic soil groups. Times of
concentration shall be determined based upon distance, slopes, and
surface materials. A minimum time of concentration to be uses shall
be 0.1 hour.
(2)
Pipe flow calculations shall be provided for the closed drain
system based upon the "Rational Formula" as follows:
(a)
Rational Formula.
|
Q = CiA
|
|
Where:
| ||||
|
Q
|
=
|
Peak rate of flow
| ||
|
C
|
=
|
Coefficient of runoff
| ||
|
i
|
=
|
Rainfall intensity in inches per hour
| ||
|
A
|
=
|
Area of watershed in acres
| ||
(b)
A weighted coefficient of runoff "C" is to be determined for
each incremented drainage area based on the following minimum values:
|
Roofs and pavement
|
0.90
| |
|
Lawns, flat (2% maximum), sandy soil
|
0.10
| |
|
Lawns, average (2% to 7%), sandy soil
|
0.12
| |
|
Lawns, steep (> 7%), sandy soil
|
0.18
| |
|
Lawns, flat (2% maximum), heavy soil
|
0.15
| |
|
Lawns, average (2% to 7%), heavy soil
|
0.20
| |
|
Lawns, steep (> 7%), heavy soil
|
0.30
| |
|
Woodland
|
0.20
| |
|
Wetlands, ponds, basins
|
0.90
|
(c)
Rainfall intensity.
(3)
Inlets shall provide capacity to accommodate the design storm.
Spread shall not encroach on travel lanes of streets or the top of
curbs or berms.
(4)
Stormwater basin analysis shall be based upon Technical Release
20 (TR-20) as follows:
(b)
Curve Number (CN).
[1]
Weighted curve numbers shall be calculated using the following
values. For cover types not stated, refer to TR-20.
|
Hydrologic Soils Group
| |||||
|---|---|---|---|---|---|
|
A
|
B
|
C
|
D
| ||
|
Lawns, poor
|
68
|
79
|
86
|
89
| |
|
Lawns, fair
|
49
|
69
|
79
|
84
| |
|
Lawns, good
|
39
|
61
|
74
|
80
| |
|
Impervious areas, pavement, roofs
|
98
|
98
|
98
|
98
| |
|
Woods, poor
|
45
|
66
|
77
|
83
| |
|
Woods, fair
|
36
|
60
|
73
|
79
| |
|
Woods, good
|
30
|
55
|
70
|
77
| |
|
Wetlands, ponds, basins
|
98
|
98
|
98
|
98
| |
[2]
Curve Numbers for conditions not included in the above shall
be obtained from TR-20 documentation.
F.
Design storms.
(1)
Stormwater runoff shall be analyzed for the two-year-frequency
storm event, ten-year-frequency storm event, twenty-five-year-frequency
storm event, and one-hundred-year-frequency storm event.
(2)
The design storm for all components of the closed stormwater
collection system, including catch basin grates and other inlets,
drain lines, and the bypass capacity of separator structures, is the
twenty-five-year-frequency storm event.
(3)
The design storm for cross culverts and devices protecting occupied
buildings is the one-hundred-year-frequency storm event.
(4)
The design storm for surface stormwater basins and subsurface
absorption systems is the one-hundred-year-frequency storm event.
The runoff for design of surfaces providing sheet flow, swales, and
drainage ditches that convey runoff to surface stormwater basins and
subsurface absorption systems is the excess runoff resulting from
storm events greater than the twenty-five-year-frequency storm event
but less than the one-hundred-year-frequency storm event.
(5)
The required recharge volume is the volume resulting from multiplying
the factors set forth below times the total post-development impervious
surface within the project area for each National Resource Conservation
Service Hydrologic Soil Group as set forth hereinafter.
|
Hydrologic Soil Group
|
Required Recharge
(inches of runoff)
| |
|---|---|---|
|
HSG A Soil
|
0.60
| |
|
HSG B Soil
|
0.35
| |
|
HSG C Soil
|
0.25
| |
|
HSG D Soil
|
0.10
|
(6)
The water quality volume to be treated is 1.0 inch of runoff
multiplied by the total post-development impervious surface within
the project area for discharges to critical areas and 0.5 inch of
runoff multiplied by the total post-development impervious surface
within the project area for discharges to all other areas. Discharges
to critical areas include systems accommodating runoff from land uses
with higher potential pollutant lands, discharges to areas with infiltration
rates greater than 2.4 inches per hour, and discharges to a designated
Zone II.
G.
Design criteria.
(1)
The closed stormwater collection system shall accommodate the
design storm without surcharging and shall provide a free discharge
to stormwater basins above the maximum the one-hundred-year storm
elevation. All components of the system shall accommodate the design
storm, including catch basin grates and other inlets, drain lines,
and the bypass components of water quality structures.
(a)
Cross culverts and devices protecting occupied buildings shall
accommodate the design storm event without surcharging.
(b)
Surface stormwater basins and subsurface absorption systems
shall have the volume to accommodate runoff providing for no increase
in the peak rate of discharge or the volume of discharge at the project
boundary for the two-year-frequency storm event, ten-year-frequency
storm event, twenty-five-year-frequency storm event, and one-hundred-year-frequency
storm event. Base flow from underdrains shall be included in the design
flow. Inflow volume shall not be decreased based upon runoff captured
by roof water recharge systems.
(c)
Surfaces providing sheet flow, swales, and drainage ditches
conveying excess runoff to surface stormwater basins and subsurface
absorption systems shall accommodate runoff from storm events exceeding
the capacity of the closed stormwater collection system but less than
the one-hundred-year-frequency storm event.
(d)
Recharge facilities accommodating runoff from paved surfaces
shall be provided over broad areas of the site and shall recharge
the design storm within 72 hours following cessation of precipitation.
Separate roof water recharge facilities shall be provided in proximity
to the building served to promote recharge over broad areas of the
site and shall recharge the design storm within 72 hours following
cessation of precipitation. Recharge facilities accommodating runoff
from paved surfaces in combination with recharge facilities accommodating
runoff from building roofs shall accommodate the required recharge
volume.
(e)
Water quality components shall be provided for the water quality
volume. Water quality components include deep catch basin sumps, water
quality structures, and sediment forebays.
(f)
Water quality components shall abate phosphorous loadings in
stormwater in accordance with the Massachusetts Stormwater Handbook.
(g)
Inflows and outflows across the project boundary shall be maintained.
There shall be no concentration of flow at any point on the project
boundary unless a downgradient easement is provided extending to an
existing watercourse or wetland.
(h)
There shall be no new point source discharge within 100 feet
of a bordering vegetated wetland. Surface stormwater basins and subsurface
absorption systems shall not be located within bordering vegetated
wetlands. Stormwater basin discharges shall be above any one-hundred-year
jurisdictional flood elevation. Surface stormwater basins and subsurface
absorption systems shall not be located within floodplains.
(2)
The closed stormwater collection system shall consist of precast
concrete drain manholes, precast concrete catch basins, precast concrete
water quality structures connected by straight segments of drain line.
(a)
Cross culverts shall consist of straight segments of Class IV
reinforced concrete pipe with gasketed joints.
(b)
The velocity of drain lines shall be determined based upon Manning's
Equation:
|
V
|
=
|
1.486
n
|
R2/3
|
S1/2
|
|
Where:
| ||
|
V is the cross-sectional average velocity (ft/s)
| ||
|
n is the Manning coefficient of roughness (independent of units)
| ||
|
R is the hydraulic radius (feet)
| ||
|
S is the slope of the drain line (feet/foot)
| ||
(c)
The capacity of drain lines shall be based upon the discharge
formula:
|
Q = AV
|
|
Where:
| ||
|
Q is the volume of flow in cubic feet per second
| ||
|
A is the cross-section area of the pipe
| ||
|
V is the cross-sectional average velocity (ft/s)
| ||
(d)
The coefficient of roughness (Manning's n) for reinforced concrete
pipe shall be 0.013 and for smooth interior wall HDPE pipe shall be
0.012.
(e)
The minimum velocity (flowing full) for all drain lines shall
be 2.5 feet per second, and the maximum velocity (flowing full) shall
be 12 feet per second flowing full.
(f)
Drain lines shall be Class IV reinforced concrete pipe with
O-ring seal joints conforming to ASTM C443. Corrugated polyethylene
pipe with smooth interior walls conforming to AASHTO M294, Type S
with O-ring seal joints may be used outside streets for systems that
will remain forever private. The minimum pipe size shall be 12 inches
in diameter. In instances where pipe diameter increases, the change
shall be provided at a manhole and the crown of the inflow pipe shall
match the crown of the outflow pipe.
(g)
Catch basins shall be five-foot inside diameter and shall have
a minimum four foot deep sump. Catch basins shall be provided at intervals
not to exceed 300 feet on center.
(h)
Separator structures having capacity to treat the water quality
volume shall be provided upgradient of all surface stormwater basins
and subsurface absorption systems and shall have a bypass capability
for larger storms. Separator structures must accommodate cleaning
with a clamshell bucket. Separator structures requiring use of a vacuum
hose for cleaning shall not be used.
(i)
Pipe shall have the structural strength to accommodate depth
of bury or surface loads. All drainage structures shall accommodate
AASHTO SH20-44 loadings.
(3)
Roof water recharge systems, surface stormwater basins and subsurface
absorption systems shall located in areas of permeable soil where
there is a minimum of four feet of naturally occurring permeable soil
between the bottom of the separate roof water recharge system, surface
stormwater basin, or subsurface recharge system and impervious soils
or bedrock. A minimum separation of two feet shall be provided between
the bottom of the separate roof water recharge system, surface stormwater
basin, or subsurface recharge system and seasonal high groundwater.
(a)
Design infiltration rates for roof water recharge systems, surface stormwater basins and subsurface absorption systems shall be either the value obtained from permeability tests of Subsection D(2) or the values set forth in the following table, whichever is less:
|
Table 2-1
Infiltration Rates for Various Soil Textures
| |||
|---|---|---|---|
|
Texture Class
|
NRCS Hydrologic Soils Group
|
Design Infiltration Rate
(inches per hour)
| |
|
Sand
|
A
|
8.27
| |
|
Loamy sand
|
A
|
2.41
| |
|
Sandy loam
|
B
|
1.02
| |
|
Loam
|
B
|
0.52
| |
|
Silt loam
|
C
|
0.27
| |
|
Sandy clay loam
|
C
|
0.17
| |
|
Clay loam
|
D
|
0.09
| |
|
Silty clay loam
|
D
|
0.06
| |
|
Sandy clay
|
D
|
0.05
| |
|
Silty clay
|
D
|
0.04
| |
|
Clay
|
D
|
0.02
| |
(4)
Separate roof water recharge systems shall be provided having
sufficient volume to accommodate one inch of runoff from roofs. Roof
water recharge systems shall be located in areas of permeable soil.
Where roof water recharge facilities are located within hydrologic
soils group (HSG) D soils, dry wells at the same elevation interconnected
with equalizing pipes or linear systems of galleys shall be used.
(5)
Surface stormwater basins.
(a)
Surface stormwater basins, including retention basins, detention
basins, and basins providing both retention and detention, shall be
designed with the following objectives to be considered: hydraulic
function, safety, maintenance, aesthetics and, when required, water
quality.
(b)
Surface stormwater basins shall be designed for aesthetics as
well as function by proving a naturalistic freeform layout and attractive
plantings.
(c)
Surface stormwater basins may be designed as detention basins,
retention basins, or combined detention/retention basins, provided
that the design requirement that there be no increase in the peak
rate of stormwater discharge and no increase in the volume of stormwater
discharge at the property line is achieved by the overall stormwater
management system. All detention basins, retention basins, or combined
detention/retention basins shall be located in areas of pervious soil
and shall be designed to empty such that the required design volume
is available within 72 hours following the cessation of precipitation.
(d)
The design elevation of the bottom of the basins shall be set
to provide a minimum two-foot separation between the bottom of the
basin and spring high groundwater. A minimum of four or more feet
of naturally occurring permeable soil shall be provided between the
bottom of the basin and impervious soil or bedrock.
(e)
Details of inlet and outlet control structures and the infiltration
system at the bottom of the basin shall be provided.
(f)
One foot of freeboard shall be provided above the one-hundred-year
design elevation of the basin.
(g)
An emergency spillway above the one-hundred-year design elevation
of the basin shall be provided for all basins that provides an unencumbered
hydraulic connection and directs excess flow in a manner that avoids
damage to public and private property and wetland resource areas.
(h)
Stormwater basin side slopes shall have a maximum slope of three
horizontal to one vertical (3 to 1). The Board reserves the right
to limit the depth of basins to the twenty-five-year design water
surface to four feet maximum. The Board reserves the right to require
forty-eight-inch-high nonclimbable fencing surrounding the basin for
safety based upon the nature of on-site and neighboring land uses.
Guardrails shall be provided for basins in proximity to vehicular
areas.
(i)
Basin embankments having a height of greater than four feet
between the required freeboard elevation and finished grade exterior
to the basin shall require geotechnical testing and an embankment
design prepared by a Massachusetts geotechnical professional engineer.
Sections through such embankments shall be provided and shall show
slopes, impervious cores, and surface armoring.
(j)
Infiltration systems within detention/retention basins are required
in the bottom of basins. Frames and grates shall be placed six inches
above the basin floor to allow sediment to settle.
(k)
Surface stormwater basins, including surrounding maintenance
access berms, shall be provided on separate lots not part of any building
lot. A ten-foot-wide minimum access and maintenance easement shall
extend from the public way to the stormwater basin lot.
(l)
A vehicle-accessible level berm for maintenance access shall
be provided surrounding each surface retention/detention basin or
underground leaching structure. The level berm shall extend for a
minimum of 15 feet (or the width recommended in the current edition
of the Massachusetts Stormwater Handbook, if greater) beyond the required
freeboard line on the side slope of surface retention/detention basins
and 15 feet beyond the structure or distribution piping of underground
leaching basins.
(m)
To facilitate screening of the stormwater basin, a tree easement
having a minimum width of 10 feet shall be provided around surface
stormwater basins and subsurface absorption systems located adjacent
to and outside the vehicle accessible level berm. Required plantings
within the tree easement consist of evergreen trees planted at a maximum
of 15 feet on-center in each row. Two rows are required that are staggered
to enhance screening. A single row of evergreen shrubs having a minimum
height of six feet at maturity shall surround the trees. Trees shall
be spruce or fir and have a minimum height of eight feet in height
at the time of planting.
(n)
The edge of surface stormwater basins shall be measured at the
required freeboard elevation. Surface stormwater basins shall comply
with minimum setbacks as follows:
(6)
Subsurface recharge systems.
(a)
Subsurface absorption systems shall be designed with the following
objectives to be considered: hydraulic function, safety, and maintenance.
(b)
Subsurface absorption systems shall meet the design requirement
that there be no increase in the peak rate of stormwater discharge
and no increase in the volume of stormwater discharge at the property
line. All subsurface absorption systems shall be located in areas
of pervious soil and shall be designed to empty such that the required
design volume is available within 72 hours following the cessation
of precipitation.
(c)
The design elevation of the bottom of the system shall be set
to provide a minimum two-foot separation between the bottom of the
basin and spring high groundwater. A minimum of four or more feet
of naturally occurring permeable soil shall be provided between the
bottom of the basin and impervious soil or bedrock.
(d)
An emergency overflow shall be provided for all systems that
directs excess flow in a manner that avoids damage to public and private
property and wetland resource areas.
(e)
Subsurface absorption systems shall consist of precast concrete
structures capable of supporting HS20-44 loadings. HDPE recharge systems
capable of supporting HS20-44 loadings may be used for systems that
will remain forever private. Subsurface absorption systems shall be
embedded in a minimum one-foot-thick layer of double-washed 3/4 to
1 1/2 inch stone on the top and sides. The top and sides of the
stone shall be surrounded by filter fabric.
(f)
The treatment train shall provide for 44% of total suspended
solids removal prior to inflow into the subsurface absorption system.
(g)
Subsurface absorption systems serving land subdivisions shall
be provided on separate lots not part of any building lot. A ten-foot-wide
minimum access and maintenance easement shall extend from the public
way to the stormwater basin lot.
(h)
To facilitate maintenance, each structure shall be provided
with a twenty-four-inch-diameter frame and cover adjusted to finished
grade at the inlet and outlet. Additional access covers shall be provided
such that no portion of any subsurface recharge systems shall be more
than 50 feet from an access cover.
(i)
The edge of subsurface absorption systems shall be measured
at the outer edge of washed stone or the outer wall of the recharge
structure, whichever extends further outward. Subsurface absorption
facilities shall comply with minimum setbacks as follows:
H.
Mounding.
(1)
A mounding analysis is required when the vertical separation
from the bottom of an exfiltration system to seasonal high groundwater
is less than four feet and the recharge system is proposed to attenuate
the peak discharge from a ten-year or higher twenty-four-hour storm.
The mounding analysis must demonstrate that the required recharge
volume is fully dewatered within 72 hours. The mounding analysis must
also show that the groundwater mound that forms under the recharge
system will not break out above the land or increase the water elevation
in a bordering vegetated wetlands, open water areas within the seventy-two-hour
evaluation period.
(2)
A mounding analysis is also required when recharge is proposed
at or adjacent to a site classified as contaminated, was capped in
place, or has an activity and use limitation (AUL) that precludes
inducing runoff to the groundwater, pursuant to MGL Chapter 21E and
the Massachusetts Contingency Plan, 310 CMR 40.0000; or is a solid
waste landfill pursuant to 310 CMR 19.000; or groundwater from the
recharge location flows directly toward a solid waste landfill or
21E site. In this case, the mounding analysis must determine whether
infiltration of the required recharge volume will cause or contribute
to groundwater contamination.
(3)
The Hantush (Hantush 1967 - See Reference for Standard 3) or
other equivalent method may be used to conduct the mounding analysis;
however, the Planning Board may require use of a numeric model for
larger systems or where required to accurately model groundwater conditions.
I.
Off-site discharge.
(1)
In instances where no lots can be developed within a subdivision because no naturally occurring soils are found within the project site which would allow recharge of stormwater within 72 hours, the applicant may petition to allow off-site discharge of stormwater. The Planning Board may waive applicable requirements of Subsection A(14), provided that, after due consideration, that waiver of strict compliance with the provisions of Subsection A(14) is in the public interest.
(2)
Runoff may be conveyed to surface stormwater basins or subsurface
absorption systems on contiguous properties that fully contain the
off-site surface stormwater basins or subsurface absorption systems
and have sufficient capacity to attenuate the increase in peak rate
and volume. The hydrologic analysis shall establish a design point
at the outlet of the surface stormwater basins or subsurface absorption
systems. Permanent easements shall be furnished encompassing all off-site
stormwater management facilities and providing proper access for maintenance.
(3)
Runoff may be discharged to the municipal storm drain system,
provided that the off-site connection conforms to the requirements
set forth herein. Detention basins are provided on the project site
having sufficient capacity to limit the post-development peak rate
of stormwater discharge to the municipal system such that it is no
greater than the pre-development peak rate of stormwater discharge
to the municipal system. Any increase in the volume of stormwater
runoff discharged to the municipal storm drain system will not cause
erosion or increase flooding or ponding of water in a manner that
would damage properties or wetland resource areas. All off-site components
of the receiving municipal storm drain system shall have sufficient
excess capacity such that they can accommodate runoff from the project
site plus all runoff from full build out of all properties in its
existing service area for the twenty-five-year-frequency storm event
without surcharging. The Board of Selectmen may allow the connection
and may, as a condition of allowing the connection, impose a user
fee to be paid by the applicant.
J.
Lot drainage.
(1)
Required drainage. Specific grading and lot drainage facilities
shall be shown for subdivisions requiring special permit authorization,
and the lot drainage requirements of this section shall be referenced
on the lot layout sheets for conventional subdivisions.
(2)
Lots shall be prepared and graded in such a manner that development
of one lot shall not cause detrimental drainage on another; if provision
is necessary to carry drainage to or across a lot, an easement or
drainage right-of-way of a minimum width of 20 feet and proper side
slopes shall be provided. Storm drains shall be designed in accord
with the specifications of the Board. Where required by the Planning
Board or the Board of Health, the applicant shall furnish evidence
that adequate provision has been made for the proper drainage of surface
and underground waters from any lot or lots. Stormwater shall not
discharge overland across lot lines unless stormwater easements are
provided.
(3)
Stormwater runoff for the two-year-frequency storm event shall
be recharged on the lot or within groups of two or three contiguous
lots in small, shallow lawn depressions or rain gardens to the maximum
extent practicable.
(4)
Roof water shall be recharged on-site. The required recharge
volume shall be one inch of runoff in permeable soils, Aquifer Protection
Districts, and Surface Water Protection Districts and 1/2 inch of
runoff for other sites in accordance with the DEP Stormwater Handbook.
(5)
LID Drainage. The Board strongly encourages use of the on-lot
stormwater management improvements listed hereinafter.
(a)
Rain gardens and small on-lot lawn depressions for roof water
recharge should be provided to accommodate roof water and surface
water runoff.
(b)
Porous pavement should be used for driveways, walkways, patios,
and other hardscape elements.
(c)
Portions of each lot should be maintained as a natural vegetation
area.
(d)
Lot grading, including driveway grading, should disconnect lot
runoff from the street drainage system.
(e)
No discharge of runoff from driveways to the street storm drain
system.
(f)
Use of porous pavement for driveways, walkways, and patios.
K.
Construction.
(1)
Drainage facilities shall be provided as indicated on the plan
and in conformity with the requirements of Sections 200, 220 and 230
of the Standard Specifications.
(2)
The standard depth of catch basin sumps shall be four feet below
the invert of the outlet pipe.
(3)
Manholes shall be constructed to the required depth at each
junction point and as shown on the plan. Pipe culvert and pipe drains
shall be in conformity with the requirements of Section 230 for installation
of pipes.
(4)
All drain pipes except subdrains shall be reinforced concrete
pipe and shall be installed according to the size as shown on the
plans. No backfilling of pipes shall be done until the installation
has been inspected by the Town Engineer. All drainage trenches shall
be filled with clean gravel borrow in accordance with Section 150,
Embankment, of the Standard Specifications.
(5)
Subdrains cannot be used to lower the water table within Water
Resources Protection Districts.
(6)
No drainage pipes from roof drains, driveway drains, or other
on-lot sources shall be connected to the street drainage system without
the explicit approval of the Planning Board and the Town Engineer.
(7)
Cast-iron manhole covers and catch basin grates shall be as
manufactured by or equivalent to E.L. LeBaron Foundry Model No. LK-110
for manholes, No. L.F. 248-2 for catch basins, or for catch basins
at the end of or on 5% gradient roads No. LK-120A (Cascade Grate).
A.
Open space. Before approval of a plan, the Board may also, in proper
cases, require the plan to show a park or parks, suitably located
for playground or recreation purposes or for providing light and air.
The park or parks shall not be unreasonable in area in relation to
the land being subdivided and to the prospective uses of such land
and shall be at least equal to one acre of land for each 20 single-family
dwelling units or fraction thereof shown on the plan. It shall be
equal to three times the floor area of all other dwelling units, and
10% of the land area for all nonresidential subdivisions. The Board
may, by appropriate endorsement on the plan, require that no building
be erected upon such park or parks without its approval for a period
of three years. Each area reserved for such purpose shall be of suitable
area, dimensions, topography and natural character for the purposes
of a park and/or playground. The area or areas shall be so located
as to serve adequately all parts of the subdivision as approved by
the Board. The Board may require that the area or areas reserved shall
be located and laid out so they may be used in conjunction with similar
areas of adjoining subdivisions, or of probable subdivisions. Any
land so reserved shall be graded to dispose properly of surface water
and shall be left in condition for the purpose intended, as required
by the Board. Compensation shall be made for land acquired in this
manner as provided in MGL c. 41, § 81Q.
B.
Protection of natural features. Every effort shall be made in both design and construction to preserve and protect all natural features, such as trees, wooded areas, watercourses, scenic points, historic spots, and similar community assets, which if preserved will add attractiveness and value to the subdivision. Any clearance, backfilling, cutting, thinning or other disturbance to trees in excess of 12 inches in diameter, measured four feet above grade, located within the street layout or in areas marked on the plan to remain natural and within an area 10 feet from and parallel to the street line, shall be prohibited, unless deemed both proper by the Board and not in conflict with the intent of this § 340-4.6. Any proposed clearance of trees shall be shown on the plan and a reason for tree clearance may be requested by the Board. The reasons for tree clearance should be provided to the Board in writing.
C.
Retained trees.
(1)
Existing trees to be retained within the right-of-way plus the
ten-foot strip parallel thereto shall be marked in the field to avoid
accidental damage. Grade within the drip line of such trees shall
not be changed more than six inches, and not less than 25% of that
area shall be retained within four inches of present grade. Tree wells
or retaining walls shall be used where necessary to accomplish this,
and shall be of fieldstone with a thickness at any point of not less
than 1/3 the depth below retained grade, unless an alternative is
detailed in the plan submittals and approved by the Planning Board.
(2)
Dead or diseased limbs shall be removed. Retained trees within
the street right-of-way shall normally have branches removed to provide
six feet of clear height above finished grade.
D.
Planted trees.
(1)
Street trees shall be spaced with one tree on the average of
35 feet apart on each side of proposed roadways. Trees shall be planted
within a tree easement that is 20 feet in width along the edge of
the right-of-way.
(2)
Trees shall be well-rooted nursery-grown stock free of injury,
harmful insects and diseases. They shall be well-branched, and the
branching structure shall be sound. The caliper at four feet above
grade shall be 2 1/2 inches. Trees not meeting the 2 1/2
inches caliper will not be accepted by the Tree Warden and will require
removal and replacement by the contractor at the sole expense of the
contractor.
(3)
Trees shall be of any of the following species:
|
Acer rubrum
|
Red maple
| |
|
Celtis occidentalis
|
Common hackberry
| |
|
Fraxinus americana
|
White ash
| |
|
Liquidambar styraciflua
|
American sweetgum
| |
|
Nyssa sylvatica
|
Tupelo
| |
|
Quercus alba
|
White oak
| |
|
Quercus coccinea
|
Scarlet oak
| |
|
Quercus palustris
|
Pin oak
| |
|
Ulmus rubra
|
Red elm
| |
|
Quercus rubra
|
Red oak
|
(a)
Trees on one side of the street may be set either opposite or
diagonally to trees on the opposite side of the roadway.
(b)
All trees shall be planted in a hole at least 1 1/2 feet
in diameter larger than the tree root system ball and one foot deeper
than the bottom of the root system ball. All trees shall be backfilled
and planted with a quality grade of loam mixed with bog peat and organic
fertilizer such as dehydrated manure, or formulated compost. All trees
shall be supported with two stakes, two inches by two inches by seven
feet. Trees shall be attached to stakes by single-strand wire with
a garden hoe utilized for protection around the tree trunk. Trees
shall be watered in during planting using a minimum of 10 gallons
per tree. After the tree is planted, a minimum three-inch layer of
fine-textured bark mulch shall be applied.
(c)
From the time of planting through one full growing season after
the issuance of the occupancy permit for the structure or structures
on the lot in front of which the tree(s) is/are located, the subdivider
shall be responsible for maintenance of planted trees and replacement
of those which have died or become diseased.
E.
Other plantings.
(1)
All areas within the right-of-way, including cul-de-sac islands
as well as unbuildable parcels along road rights-of-way which are
not paved, shall either be loamed and seeded for grass or, where some
or all natural vegetation is retained or to be restored, shall be
mulched and planted, with designation of the type of treatment to
be made by the Planning Board, taking into consideration the designated
treatment of adjacent lots, the long-term maintenance of the planting
and the feasibility of successfully retaining existing vegetation.
In general, durable, low-maintenance native plantings are preferred
over loam and seed treatments.
(2)
Areas to be planted in grass shall have loam placed to a compacted
depth of six inches. The grass seed shall be creeping red fescue and
perennial rye grass and shall otherwise conform to Section M6.03.0
of the Standard Specifications. It shall be placed at the rate of
four pounds per 1,000 square feet and shall be properly fertilized
and watered with uniform coverage to keep the seeded areas moist.
After growth has started, seeded areas shall be watered regularly
to a minimum depth of two inches until the performance guarantee is
released.
(3)
Areas to have natural vegetation shall have supplemental plantings
as directed by the Planning Board or its agent, and shall be covered
with clean pine bark mulch or other appropriate mulch material, to
a depth of at least three inches, and watered if necessary until the
performance guarantee is released.
F.
Revegetation. To minimize erosion, all disturbed areas shall be stabilized
within 14 days. Permanent revegetation or paving shall be completed
within 60 days following first disturbance.
A.
Width. Where utilities cross lots or are centered on rear or side
lot lines, easements shall be provided of a width of at least 20 feet.
B.
Stormwater easements. Where a subdivision is traversed by a watercourse,
drainage way, channel or stream, the Board shall require a stormwater
easement or drainage right-of-way of adequate width and proper side
slope as determined by the Town Engineer to conform substantially
to the lines of such watercourse, drainage way, channel or stream
and to provide for construction or other necessary purposes. In no
case shall the width be less than 20 feet or the side slope be steeper
than two horizontal on one vertical.
C.
Access. Access easements or parcels to adjacent property shall be
provided, if required by the Board, for use by emergency vehicles
and for the benefit of the Town. They shall be a minimum width of
20 feet.
D.
Layout. Wherever possible, easements along rear lot lines shall be
continuous to the street at the end of the block to connect with the
adjoining blocks in the shortest direct line.
E.
Construction easements. Temporary construction easements shall be
reserved over all lots to the benefit of the developer and the Town
of Sharon to allow installation, maintenance, and repair of any required
subdivision improvements located on private lots, including, without
limitation, driveways, slopes, walls, roof water recharge systems,
stormwater management facilities, materials, and utilities.
A.
Monuments.
(1)
Monuments shall be installed on street lines at all points of
intersections of streets with each other and at all points of curvature
and at all points of change in direction.
(2)
Monuments shall be a standard permanent granite of not less
than three feet six inches in length and not less than six inches
in width and breadth and shall have a 1/2-inch diameter hole, 1 1/2
inches deep, drilled in the center of the top surface. Said monuments
shall be installed at the time of final grading with the top flush
with the top final graded surface.
B.
Street signs.
(1)
From the time of rough grading until such time as each street
is accepted by the Town as a public way, the sign posts at the intersection
of such street with any other street shall have affixed thereto a
sign designating such street as a private way.
(2)
Street signs for each intersecting street shall be installed
at each intersection to conform to those used by the Sharon Public
Works Department and installed at a location as approved by the Public
Works Department.
(3)
In the event street signs, once erected, are damaged or vandalized,
the developer shall within seven days repair and/or replace such signs.
This requirement shall remain in force until such street and its appurtenances
are accepted by the Town.
D.
Cleanup. Any area disturbed by construction and all rights-of-way
shall be cleaned up so as to leave the area shown on the plan in a
neat and orderly appearance, free from debris, tree stumps, loose
rocks, mounds of dirt or other objectionable material. Said material
shall be removed from the site and properly disposed of.
E.
Maintenance of improvements. For the purpose of protecting the safety,
convenience and welfare of the Town's inhabitants, for the provision
of adequate access to all of the lots in a subdivision by ways that
will be safe and convenient for travel, for reducing the danger to
life and limb in the operation of motor vehicles, for securing safety
in the case of fire, flood, panic and other emergencies; under the
authority of MGL c. 41, § 81M, as amended, the applicant
or his/her successor shall provide for the proper maintenance and
repair of improvements until ownership of such improvements is accepted
by the Town. As a minimum, maintenance shall include the following:
(1)
Snow and ice control.
(a)
Sand/Salt shall be applied to all streets on which a dwelling(s)
is/are occupied so as to provide safe access to an existing public
way. Sand/Salt shall be applied in a manner consistent with the then-current
policies and procedures of the Department of Public Works.
(b)
Occupied streets shall be plowed to provide safe access to an
existing public way whenever the Department of Public Works plows
similar accepted Town ways. Generally, the Department of Public Works
will plow all streets whenever snowfall exceeds three inches in depth.
(c)
It shall be the developer's responsibility, prior to November
1 of each year, to prepare and coordinate a snow/ice control plan
with the Superintendent of Public Works. Upon approval of such plan
by the Superintendent of Public Works, the developer shall file copies
with the Planning Board and the Department of Public Works.
(2)
Street sweeping. As a minimum, the developer shall cause all
streets on which a dwelling(s) is/are occupied to be swept monthly.
The developer shall maintain an accurate record of all street sweeping
activity in his/her development and shall provide copies of same to
the Town Engineer. A final sweeping shall be performed at least two
weeks but not more than four weeks prior to consideration for acceptance
of every street by Town Meeting.
F.
Flood hazard avoidance. Any subdivision located in any part within
the Flood Hazard District established under the Zoning Bylaw[1] shall comply with the following:
(1)
Subdivision design shall be consistent with the need to minimize
flood damage within the flood-prone area, through use of clustering,
open space reservation, street profile design, and drainage.
(2)
All public utilities and facilities, such as sewer, gas, electrical
and water systems, shall be located and constructed to minimize or
eliminate flood damage.
(3)
Drainage systems shall be designed in consideration of possible
flooding to the base flood elevation.
G.
Maintenance of improvements. Stop signs and stop bars on the pavement shall be installed by the developer at those intersections, whether public or private, where the warrants for stop signs are satisfied. Stop signs shall be erected and maintained as specified for street signs per § 340-4.8B of these rules and regulations. Stop signs shall conform to the Manual on Uniform Traffic Control Devices and be placed as determined by the Superintendent of Public Works. All intersections, roadways and roadway systems shall include a "traffic control plan," prepared by a registered traffic engineer, which shall include pavement markings, signage and lighting. Any intersection meeting the warrants for signalization as set forth in the Manual on Uniform Traffic Control Devices shall be provided with a complete traffic control system.
