A.
Street alignment.
(1)
Horizontal alignment shall have:
(a)
A minimum radius between intersections of 150 feet.
(b)
A minimum radius of 10 feet at the property line at the intersection
of street rights-of-way, except that intersections of any highway
with a major street shall have a minimum radius of 40 feet, and those
with a minor street shall have a radius of 20 feet.
(2)
Vertical alignment shall have:
(a)
A minimum grade of 1/2 of 1%.
(b)
Desirable maximum grade of 8%; 10% on minor streets.
(c)
A maximum grade of 3% within 100 feet of the intersection between
a major and minor street.
(d)
All changes in grade of more than 1% shall be connected by a
vertical curve and shall have a minimum length of 100 feet.
(4)
Standards for all highways shall be determined by the Planning Board
with advice from the Highway Superintendent, the Public Works Department
or the Town Engineer.
B.
Guideline construction types.
(1)
Subgrade.
(a)
The entire right-of-way shall be cleared of brush and trees,
except those which will be an asset to subdivision landscape.
(b)
All boulders, organic material, soft clay, spongy clay and other
objectionable material shall be removed and replaced with suitable
material.
(c)
The subgrade shall be suitably stabilized, shaped, rolled and
uniformly compacted with a ten-ton roller to conform to lines and
subgrades and typical cross sections of this specification and the
approved final plat profile drawings. The process of shaping, rolling
and filling shall be repeated until no depressions develop.
(d)
After the subgrade has been completed, all rutting displacement
or soft spots shall be properly repaired with new material, regraded
and compacted.
(e)
When existing materials in the road are to be used for road
base material, that material shall be removed to the surface of the
subgrade so that the subgrade may be properly prepared before the
base is constructed.
(f)
Cuts and fills shall have a maximum slope of one on two from
the edge of the right-of-way, except when specifically waived by the
Planning Board for the purpose of saving trees or some other particular
terrain feature at the given place.
(2)
Paving.
[Amended 7-10-1989 by L.L. No. 1-1989]
(a)
The base shall consist of two layers of selected run of bank
gravel: the first layer shall consist of a nine-inch compacted thickness
gravel properly shaped and compacted with a ten-ton roller until no
displacement occurs; the second layer shall consist of three inches
of Item four gravel shaped and rolled with a ten-ton roller until
no displacement occurs.
(b)
Paving shall consist of one three-inch layer of dense binder
bituminous concrete.
(3)
Curbs and gutters (see drawing, Typical Curb and Gutter Cross Section,
for dimensions).[1] Detailed specifications should be made available in the
Town Engineer's office. Integral curb and gutter will be required
on all streets.
[1]
Editor's Note: Said drawing is included at the end of this chapter.
(4)
Pavement crown (see drawing, Typical Street Section).[2] Pavement cross section shall be a modified parabolic configuration
with the center-line elevation being equal to the top of curb elevations.
[2]
Editor's Note: Said drawing is included at the end of this chapter.
(5)
Driveway aprons (see drawing, Typical Driveway Details).[3]All driveways or other parking areas shall have driveway
aprons extending from the curbline to the property line. Driveway
aprons shall be of the same construction as the street paving or better.
Driveway aprons shall be at least 10 feet wide at the curb face and
at least eight feet wide at the property line.
[3]
Editor's Note: Said drawing is included at the end of this chapter.
(6)
Street signs. Street signs shall be provided by the appropriate municipal
agency.
(7)
Planting strips. All planting strips within the street right-of-way
shall be finished, graded, properly prepared and seeded or sodded
with lawn grass in conformance with good nursery and landscape practice.
A.
All gas, electric, telephone, sewer and water lines shall be installed
in accordance with the specifications of the agency, utility company
or government authority or special district which has jurisdiction
in the area.
B.
A letter approving such a proposed installation and a statement as
to who will carry out the construction signed by a responsible official
of the agency, utility company or government authority or special
district which has jurisdiction in the area shall be directed to the
Chairman of the Planning Board and shall be received prior to final
plat approval.
A.
Grading and drainage system plan (subject to review and approval
of the Soil Conservation Service, United States Department of Agriculture).
(1)
A grading and drainage system plan shall be part of a preliminary
plat (major subdivision) and final plat (minor subdivision) and shall
be in conformance with the municipality's stormwater plan, where applicable.
It shall indicate a proposal for an adequate system of drainage structures
to carry off and store or discharge the stormwater runoff and material
drainage water which originates not only within the property boundaries
but also that which originates beyond the property boundaries.
(2)
The public improvement and utilities plan and profiles shall show
the final drainage plan and street profiles. They shall be prepared
and submitted with the final plat and shall be reviewed and approved
by the Town Engineer.
(3)
No stormwater runoff or natural drainage water shall be so diverted
as to overload existing drainage systems or create flooding or the
need for additional drainage structures on other private properties
or public lands without proper and approved provisions being made
for taking care of these conditions.
B.
Brooks or ditches. Where brooks or ditches are used as outlets, they
shall be designed by the use of Manning's formula as indicated for
collection systems, with the following considerations:
(1)
Slopes for ditches shall all be not more than one on two.
(2)
Design velocities in earth ditches shall not exceed three feet per
second.
(3)
A ditch or brook right-of-way, of sufficient minimum width to include
a ten-foot access strip, in addition to the width of the ditch or
brook from bank top to bank top, shall be offered for dedication to
the Town for drainage purposes. Such right-of-way shall be shown on
the drainage plan and on the final plat.
C.
General design standards.
(1)
Valley gutters will be permitted at T-intersections where they are
parallel to the center line of the through road and shall be constructed
to specifications and design to be furnished by the Town Engineer.
This is to be accomplished by gradually taking out the crown of the
intersecting street starting from a point about 30 feet back from
the flow line of the through street. At other than T-intersections,
valley gutters will be permitted only when warranted by limited traffic
use, but never across heavily traveled streets.
(2)
Surface drainage in gutters shall be limited to the equivalent of
that flowing from one and five-tenths (1.5) impervious acres.
(3)
Drainage structures which are located on county or state highways
shall be approved by the appropriate Highway Engineer's office, and
a letter of permit from that office indicating such approval shall
be directed to the Planning Board.
D.
Specification for drainage system structure.
(1)
Drop inlets.
(b)
All culverts shall be constructed of reinforced-concrete pipe
or shall be reinforced-concrete box culverts.
(c)
Culverts shall have reinforced-concrete headwalls similar to
that shown on Drawing No. 9, unless another detail is approved for
a specific installation.[2]
[2]
Editor's Note: Said drawing is included at the end of this chapter.
(d)
A chain link fence four feet high shall be provided along the
highway right-of-way line at the headwall on each end of the culvert
and shall extend a minimum of four feet beyond the top of the ditch
or brook bank on each side of the headwall.
(2)
Storm drainpipe.
(a)
All storm drain pipe shall be reinforced concrete or plastic,
and be in accordance with the storm drain specifications of this chapter.
Metal drain pipe shall only be used with the written consent of the
Commissioner of Public Works. All pipe shall be laid on undisturbed
subgrade with full, firm and even bearing. Backfill and compaction
shall be in accordance with good engineering practice. They shall
be indicated on the final plat with notation as to size, slope and
invert elevations. Necessary easements shall be shown on the drainage
plan and the final plat and shall be not less than ten feet wide.
[Amended 8-11-2008 by L.L. No. 9-2008]
(b)
Drainage pipe shall be a minimum of 18 inches in diameter.
Monuments. All monuments shall be constructed of concrete or
stone and shall be four inches square with a length of at least 36
inches or one inch in diameter deformed reinforcing rods a minimum
of 36 inches in length and shall be set at finished grade.
A.
Accurate locations of all monuments must be furnished.
B.
One monument shall be located at each corner and at each general
change in direction of the boundary.
C.
Two monuments shall be located at each street intersection.
D.
Monuments shall be located at the beginning and end of each curve
along one side of the street right-of-way.
