This article establishes and defines the public improvements
and design standards that the Township shall require in the review,
approval and construction of any subdivision or land development.
All streets of any new subdivision or land development shall
be built to the standards and specifications contained herein, and
to applicable state and federal highway department specifications
(e.g., Pennsylvania Department of Transportation Specifications, Publication
408, latest revision).
A. Subgrade.
(1) Within limits of road surface. The area within the limits of the
proposed road surface shall be shaped to conform to the line, grade
and cross-section of the proposed road.
(2) Unsuitable materials to be removed. All unsuitable subgrade materials
shall be removed or stabilized.
(3) Permits required for encroachment into wetland areas. Encroachment
into wetland areas or the Floodplain Conservation District, where
unavoidable, shall be done only after all required permits for such
encroachment are obtained from PADEP, FEMA, U.S. Army Corps of Engineers,
or other agency having jurisdiction over such areas. Where permitted,
such areas shall be permanently drained and stabilized. Subbase drains
shall be installed where deemed necessary by the Township Engineer
during construction. The proposed method of subgrade preparation for
such areas shall be detailed on the subdivision or land development
plan.
(4) Fill material: suitable, uniform and compacted. Fill material shall
be suitable and thoroughly compacted for its full width, including
shoulder areas, in uniform layers of not more than eight-inch thickness.
(5) Subgrade compacted. The subgrade beneath cartways, shoulders and
sidewalks shall be thoroughly compacted to not less than 100% of the
maximum modified proctor density.
(6) Backfill compacted. Backfill of trenches within the cartway and curb area shall be thoroughly compacted prior to application of the base course. Refer to §
185-67F for trench backfill specifications.
(7) Township inspection of subgrade. The subgrade shall be checked and
approved by the authorized Township Engineer for lines, grade, crown,
contour, suitable materials and compaction before any succeeding courses
are applied.
(8) Township inspection of roads and streets. Crown board and straight
edge shall be used for checking road and street construction. Maximum
deviation shall not exceed one-quarter of an inch.
B. Base course.
(1) Base course materials. Base course shall consist of one of the following
materials, installed as specified by PennDOT to the thickness shown
respectively below:
(a)
Crushed aggregate base course from PennDOT publication, "Seldom-Used
Specifications", eight inches thick installed.
(b)
PennDOT Schedule 3A modified stone base course, 10 inches thick
installed.
(c)
Bituminous Concrete Base Course (BCBC), four inches thick installed
on top of six inches of PennDOT subbase material.
(2) Compaction of base course. The base course shall be rolled uniformly
and thoroughly compacted according to requirements of PennDOT Publication
408. Rolling shall continue until the material does not creep or wave
ahead of the roller wheels.
(3) Extent of base course. The base course shall extend 12 inches beyond
the edge of paving on all streets constructed without a curb.
(4) Special tests of areas of fill over three feet. In fill areas over
three feet thick, compaction tests are required in each eight-inch
layer at 150-foot intervals. The tests must be performed by a certified
testing laboratory and results submitted to the Township Engineer.
All compaction must be 100% of the maximum modified proctor density.
Any layer not meeting this standard shall be removed or re-rolled
until suitable compaction is obtained.
(5) Filling of voids. After compaction of the base stone, dry screenings
shall be applied in sufficient quantity to fill all of the voids in
the rolled stone base. A vibratory roller, of PennDOT approved design,
must be used in this step of construction and rolling shall continue
until all voids are filled. Small areas around inlets and manholes
that cannot be reached by the vibratory roller shall be compacted
with a mechanical tamper or whacker.
(6) Removal of loose screenings. When the stone surface is tight and
will accept no more screenings, all loose screenings shall be removed
from the surface to expose the top 1/2 inch of the aggregate over
at least 75% of the road.
(7) No placement of materials on wet or frozen surfaces. No base material
shall be placed on a wet or frozen subgrade.
(8) Tack coat. When so required by the Township Engineer, a tack coat
shall be applied.
C. Bituminous surface.
(1) Material. Bituminous material shall be PennDOT Schedule ID-2 with
four inches of binder course and 1 1/2 inches of wearing course.
(2) Uniform slope. The completed road surface shall have a uniform slope
of 1/4 inch per foot from edge to center line, except that on super-elevated
curves, this slope shall not be less than 1/4 inch per foot and shall
extend up from the inside edge to the outside edge of the paving.
(3) Restrictions on laying of courses. No visible moisture shall be present
prior to the laying of each course. Road surface temperature shall
be 50° F. or greater prior to laying of the bituminous surface,
with the air temperature rising.
(4) Sealing of wearing courses. All wearing surface courses shall be
sealed to the concrete curb and at its joint with existing streets
and driveways with a one-foot-wide PennDOT Schedule Class BM-1 asphalt
gutter seal.
(5) Inspection by Township. Application of all bituminous layers of roadway
paving shall require full-time inspection by the Township or its authorized
representative.
D. Verification of materials. The Township shall require delivery slips
for all materials used in the construction of streets.
E. Grading and shoulders.
(1) Supporting shoulders. Supporting shoulders shall be constructed on
all sections of projects where a base course or pavement is to be
constructed without other permanent support along the sides.
(2) Grading beyond edge of paving required. Roadways shall be graded for not less than eight feet beyond the edge of the proposed paving on each side. This grading width shall be increased as necessary where sidewalks and/or planting strips are to be provided. Shoulders shall be compacted and graded with a slope of one inch per foot, unless otherwise permitted in §
185-67E(3) below. Beyond the limits of this grading, banks shall be sloped to prevent erosion but this slope shall not exceed one vertical to three horizontal to one vertical, with tops of slopes in cuts rounded. Steeper slopes shall only be permitted where excessive cut or fill would otherwise be required.
(3) Slopes of swales. In cases where swales must be provided in the right-of-way
area outside of the paved cartway, cut slopes shall be limited to
one vertical to two horizontal and fills shall be limited to one vertical
to three horizontal.
F. Backfilling of road excavations. All trenches or other excavations
in existing or proposed roads shall be backfilled in accordance with
the following:
(1) Backfilling. Backfilling shall be done as promptly as possible.
(2) Backfill materials. The trench shall be backfilled with coarse aggregate
consisting of screenings, 2RC, 2A modified or other aggregate as approved
by the Township Engineer to a height of at least one foot above the
top of the conduit, pipe or pipe bell. These screenings shall be placed
with the hand shovels and not from trucks or with the use of power
equipment and shall be free from refuse, boulders, rocks, unsuitable
organic material or other material which, in the opinion of the Township,
is unsuitable.
(3) Backfilling of pipe trenches. When the pipe is located in a dedicated
street or any place where paving (including driveways) may be placed,
the remainder of the trench shall be backfilled with 2RC or other
approved materials and promptly compacted. The backfill material shall
be mechanically tamped in approximately six-inch layers.
(4) Restoration of openings in existing roads. Where openings have been
made in existing Township roads, paving shall be restored in accordance
with the paving standards contained in this chapter. Openings made
in state roads shall be restored in accordance with the Pennsylvania
Department of Transportation specifications. Permits shall be obtained
before paving is opened in any existing state or Township road.
(5) Openings beyond curblines. Where openings are made behind the curbline,
work shall be as specified below. The opening shall be covered with
good topsoil to a depth of six inches and seeded or sodded to the
satisfaction of the Township Engineer.
(6) Refilling, recompaction, regrading. Whenever the trenches have not
been properly filled or if settlement occurs, they shall be refilled,
compacted, and graded to conform to the surface of the ground.
(7) No frozen earth to be used. Frozen earth shall not be used for backfilling,
nor shall any backfilling be done when materials already in the trench
are frozen.
(8) Unsuitable material to be removed. Where excavated material, or any
portion thereof, is deemed by the Township Engineer to be unsuitable
for use as backfill, the applicant or applicant's agent shall replace
backfill material with material approved by the Township.
G. Notification of emergency services. The applicant shall be responsible
for notifying all emergency service agencies when construction will
impact accessibility on existing roads.
Private streets will be permitted only when proper maintenance
is guaranteed by the developer and when in accordance with the requirements
outlined below. Private streets shall be clearly identified as such
on each preliminary and final plan. Deeds transferring any lots served
by such a private street shall identify the street as a private street
to be privately maintained. Private streets shall be prohibited in
nonresidential subdivisions.
A. Design standards.
(1) Widths. Private streets shall have a right-of-way of 50 feet and
a minimum paved cartway width of 16 feet. Shoulders shall be provided
to a minimum width of four feet on either side of the paving. Curbing
is not required except as deemed necessary under certain circumstances,
such as to alleviate a critical stormwater condition, or as required
by the Township Engineer.
(2) Grades. Where no further subdivision is possible, the maximum allowable grade of the paved cartway shall be 15%; otherwise, the maximum allowable grade shall be as required by §
185-65. The minimum center-line grade shall be 1% to facilitate drainage. A five-percent grade or less shall be maintained within the public road right-of-way and for a minimum of 25 feet beyond. Where a greater than five-percent grade is involved, one parking space per lot served shall be provided at the entrance from the public street adjacent to but outside of the public right-of-way.
(3) Cartway construction requirements.
(a)
Grades up to 5%:
[1]
Subgrade: construct according to §
185-67A of this chapter.
[2]
Stone base: 3A modified, six inches thick after compaction.
[3]
Stone surface: 2A modified, two inches thick after compaction.
(b)
Grades greater than 5% and up to 15%:
[1]
Subgrade: construct according to §
185-67A of this chapter.
[2]
Base course: crushed aggregate base course consisting of AASHTO
No. 1 Stone with screenings (from PennDOT publication "Seldom Used
Specifications"), six inches thick after compaction.
[3]
Stone surface: 2A modified, two inches thick after compaction.
(c)
Area along first 50 feet from public street:
[1]
Subgrade: construct according to §
185-67A of this chapter.
[2]
Base course: 2A modified, six inches thick after compaction.
[3]
Paving: The base surface course shall be shaped and rolled to
provide a two inch crown or shall be sloped laterally to facilitate
drainage and shall be covered with 1 1/2 inches of ID-2 compacted
binder course followed by one inch of ID-2 compacted wearing course.
This requirement may be reduced or waived in the event the street
that it intersects is not paved.
(4) Other construction requirements.
(a)
Intersection with public street. At the intersection with a public street, the private street shall be provided with paved twenty-five-foot radii. The intersection shall meet the sight-distance criteria of §
185-66G of this chapter. The Township may consider waiving this requirement if the public street is not paved.
(b)
Turnaround. A turnaround facility for use by passenger, service,
and emergency vehicles shall be provided within the right-of-way,
at the end of the private street most distant from the public street.
A turnaround shaped in a T or a Y configuration shall be provided,
with the top of the T being 50 feet long by 20 feet wide. In the event
the private street does not initially, but is later to be, extended
to the last house or lot on the street, the interim turnaround may
take the form of a street extension 20 feet beyond the second driveway
with the T or Y configuration turnaround.
(c)
Drainage. Drainage swales, culverts, and curbing shall be provided,
when required, to minimize stormwater and icing problems at the intersection
and along the private street length.
(d)
Backfilling. Private streets shall comply with the requirements of §
185-67F for the backfilling of road excavations.
B. Agreement.
(1) Maintenance, repair, construction and reconstruction. As a condition
to final plan approval, an agreement providing for maintenance, repair,
construction, and reconstruction, including drainage facility maintenance
and snowplowing of private streets, shall be submitted to the Township
and recorded with the approved final plan. The deed for each new or
existing lot fronting on the private street shall reference the agreement.
(2) Conditions of dedication offer. The agreement shall also contain
the conditions under which the street may later be offered for dedication.
The conditions shall state that at the time of offer for dedication
the street must conform to the Township public street specifications
or that the owners of the abutting lots shall include with the offer
of dedication sufficient money, as estimated by the Township Engineer,
for the Township to bring the street into conformance with Township
specifications in effect at the time of dedication.
C. Information required for private streets. The following information
shall be included with the (preliminary/final) subdivision plan when
a private street is proposed:
(1) Existing and proposed contours at two-foot contour intervals based
upon an accurate field topographic survey.
(2) Center-line profile of the street.
(3) Drainage details for swales and culverts.
(4) Typical cross sections of the cartway and right-of-way.
(5) Cartway construction specifications.
[Amended at time of adoption of Code (see Ch. 1, General
Provisions, Art. I)]
Design and construction of driveways shall comply with the requirements of Chapter
67, Driveways, of the Code of Newlin Township.