[HISTORY: Adopted by the Town Board of the Town of Yorktown 4-17-1990
by L.L. No. 6-1990. Amendments noted where applicable.]
These specifications may, for simplicity, be referred to as "Subdivision
and Dedication Road Specifications."
The following specifications shall apply to all roads hereafter constructed
within the Town of Yorktown, except as provided for herein, and with the additional
exceptions:
A.
These construction specifications are not intended to cover every detail of construction, but are adopted to indicate acceptable standards of materials, workmanship and construction in a general way. In any case, when a rule, regulation or provision of Chapter 195, Land Development, may conflict or be inconsistent with the provisions of these specifications, then the provisions of these specifications shall prevail and be complied with, unless modified, changed or altered as provided for herein.
B.
The Town Engineer may modify, change or alter the standards
of equipment, construction, material and workmanship in an appropriate case
so that the intent and purpose of these specifications shall be maintained.
C.
The mere approval of a road constructed in accordance
with these specifications does not obligate the Town Board to accept such
a road as a Town highway.
A.
LAND DEVELOPMENT REGULATIONS
LIMIT OF GRADING
STANDARD SECTIONS
STATE HIGHWAY SPECIFICATIONS
TOWN AUTHORITY
(1)
(2)
(3)
(4)
(5)
As used herein, the following words shall be defined
as follows:
The regulations in force and effect at any time by the Planning Board
of the Town of Yorktown governing subdivisions.
[1]A roadway cross section which is measured from the toe of a fill section across to the opposite toe. When a roadway is cut on one side and filled on the other, the disturbed cross section shall be measured from the toe of the fill section to the beginning of the cut. This limit will refer to the area which must be disturbed to accomplish the grading. All roadway grading shall be in conformance with § 255-9.
Drawings showing sections and views of roadways, drainage improvements
and other structures described by these specifications. Standard Town of Yorktown
details are available on Mylar from the Town Engineer's office (Sheet Nos.
D1 through D6).
The New York State Department of Transportation Standard Specification
Construction and Materials, in force and effect and any changes, modifications
or amendments thereto.
The Planning Board of the Town of Yorktown, in the case of a street
or highway shown on a plat or plan submitted to it for approval. After such
approval, Town authority shall mean the Town Board of the Town of Yorktown
acting directly or through its authorized representatives.
The Town Board of the Town of Yorktown, in the case of a proposed dedication.
The Town Board of the Town of Yorktown, in the case of an application
under § 280-a of the Town Law.
The Town Board of the Town of Yorktown, in the case where a variation
of maximum limit of grading or maximum roadway grade of 8% is exceeded.
The Town Board of the Town of Yorktown, in the case of building permits
for individual lots which require driveways in excess of 10%.
B.
Technical terms. All technical terms used herein are
used in their usual meaning. In case of any doubt, the meaning given to such
terms by the current State Highway specifications shall be used.
A.
No street or highway shall hereafter be built, rebuilt
or improved by other than town forces within the town, except state and county
highways and private driveways, unless and until plans therefore shall have
been approved by Town authority.
B.
The plans shall be of such character and in such detail as will assure that the work to be performed in compliance with them shall be equal to the requirements of these specifications to Chapter 195, Land Development, and to any additional requirements made by town authority at the time of approval of such plans.
C.
Such plans shall be on the same size sheets as required for plats under Chapter 195, Land Development, and two white prints or equal of each sheet shall be submitted to town authority for approval.
D.
All such streets and highways shall conform to the plans
hereinabove described and to the requirements of these specifications and
to any additional requirements made by town authority at the time of approval
of such plans.
E.
Notwithstanding anything to the contrary which may be
set forth or contained herein, these specifications shall not apply to the
following roads:
(1)
All federal, state and county roads.
(2)
Roads constructed or in the course of construction which
are shown on a subdivision map or plat heretofore approved by the Planning
Board and duly filed in the County Clerk's Office at Westchester County (Division
of Land Records), except that all roads shown on subdivision maps or plats
or on any other map, filed in the office of the County Clerk of Westchester
County (Division of Land Records) which are not required to comply with or
conform to the road specifications now in force prior to the adoption of these
specifications shall comply and conform with all of the requirements of these
specifications now being adopted, unless, by order of the Town Board, the
application of these specifications to such roads are waived or modified,
and, if modified, the extent of such modification shall be set forth by the
Town Board in a resolution adopted at a regular meeting of said Board.
(3)
All existing town roads which are part of the town highway
system and are being serviced and maintained as such.
(4)
All existing roads now being used as public highways
and which have not been accepted as town roads and are not part of the town
highway system.
A.
These specifications may, from time to time, be illustrated
by drawings showing minimum construction and design standards conforming to
these specifications and, when approved by the Town Board, shall form part
of these specifications.
B.
All materials and/or methods of construction not described
in these standards shall meet the requirements of the New York State Highway
Specifications.
C.
From time to time, minor additions and corrections may
be amended to these specifications if, in the opinion of the Town Engineer,
certain methods or materials prove to be unsatisfactory as listed herein.
D.
Approval of materials shall, in general, be handled by
the Town Engineer. Approval of methods of construction shall, in general,
be under the direction of the Town Engineer. Any variance from the standards
set forth in these specifications must be requested in writing by the builder
and approval must be in writing by the Town Engineer if such variance arises
after approval of the subdivision plat by the Planning Board.
E.
Before any work described herein is undertaken, at least
48 hours' written notice shall be given to the Town Engineer. None of the
operations required herein shall be backfilled, covered or succeeded by a
subsequent operation until approval is rendered by the Town Engineer as required.
Work performed not in accordance with these provisions cannot be accepted.
A.
Rights-of-way between outside slope lines of ditches
or gutters shall be cleared of all trees, shrubs, buildings or other structures
and all perishable matter. Within the area of the pavement, shoulders and
gutters, such perishable matter shall be removed to a depth of two feet below
finished grade.
B.
On horizontal curves, any additional width necessary
to maintain a minimum visibility of 350 feet at the paving edge shall be cleared.
C.
The Planning Board may waive the clearing of certain
trees upon request or upon its own initiative and may request certain trees
within the right-of-way be preserved.
All topsoil must be stripped from the bed of the proposed roadway and
from all surfaces to be disturbed by cut or fill, retaining a sufficient quantity
of such topsoil on the site for finish grading as required below.
A.
All streets and/or roads constructed shall be graded
for a minimum width equal to the width of the proposed pavement and two four-foot
shoulders, unless otherwise required by town authority. Side slopes shall
have a graded slope of not more than one foot vertical for each two feet horizontal
in cut or fill in earth, and not more than six feet vertical for one foot
horizontal in rock.
B.
All grading shall be done as required to complete the
streets and highways to the road profiles shown on the plans approved by the
town authority and to provide a finished cross section having the characteristics
shown on the approved plan as hereinafter stated. All cross sections shall
meet the approval of the Town Engineer.
C.
In order to reduce the amount of earth work required for roadway construction, the limit of grading shall be less than or equal to the pavement width, plus 40 feet. All grading will conform to Subsection A above. Any proposal which exceeds the maximum limit of grading shall be referred to the Town Board to waive that requirement of these specifications. Road grades in excess of 8% shall also require Town Board approval. The applicant may also apply to the Town Board for cluster authorization under § 278 of the Town Law which would allow for flexibility within these specifications.[1]
D.
Tops and bottoms of cut and fill slopes shall be set
back from existing property boundaries a distance of three feet plus 1/5 of
the height of the cut or fill, but need not exceed a horizontal distance of
10 feet.
A.
The subgrade shall be brought to the required grade by excavation or filling. Excavated materials, if suitable, may be used in making embankments filling the low areas of the work and at such places as required by the Town Engineer. Roots and stumps shall be removed as described under § 255-7, Clearing and Grubbing. Tree trunks, limbs and other perishable materials shall not be incorporated in the fill but shall be removed.
B.
The subgrade shall be formed by such repeated rolling, shaping, removal of soft spots and other unsuitable material and replacement with suitable material as specified under § 255-11, Bottom Course, rerolling and reshaping as may be deemed necessary to provide a uniform hard, stable surface properly crowned to shed water laterally to the sides.
C.
When fill is required, the fill shall be spread in layers
not to exceed 12 inches loose, bladed or diced to an even surface free from
clods and compacted by rolling with approved rollers to the satisfaction of
the Town Engineer. In no case shall boulders or rock layers be deposited within
two feet of the finished subgrade elevation. Utility trenches, areas around
culverts, bridges, retaining walls, curbs, manholes, catch basins or other
sections not accessible to the roller shall be backfilled in eight-inch layers
and compacted with approved mechanical hand tampers. Filling and compacting
operations shall continue alternately until the cut and fill conform with
the lines, grades and typical cross sections shown on the approved road plans.
A.
The foundation course for Type 1A Asphaltic Concrete
Pavement shall be a minimum of eight inches of New York State item No. 304.05
granular material placed upon a properly prepared subgrade.
B.
The material shall be spread in such depth that the thickness
of any layer, after compaction, shall have a minimum thickness of eight inches.
Water shall be added in such amounts as the Town Engineer may consider necessary
to secure satisfactory compaction. When the moisture content of the layer
is within the limits for proper compaction, the entire surface shall be rolled
with a smooth steel wheel roller having a minimum weight of 10 tons. Each
portion of the layer shall be covered by a minimum of eight passes of the
roller.
C.
In limited areas where the use of a roller is impractical
(e.g., vicinity of manholes, valve boxes, etc.), approved mechanical tampers
shall be used to compact the material. After compaction, the course shall
be true to grade and cross section, and any depressions shall be eliminated
by the use of additional granular material. In all cases, the foundation course
shall be so thoroughly compacted that it will not weave under the roller.
A.
New York State item No. 403.13, asphaltic concrete binder
course.
(1)
Upon the compacted eight inches of foundation course
shall be placed a compacted base course consisting of three inches of New
York State Highway Specification item No. 403.13.
(2)
The asphalt and the method of preparing and mixing shall
be in accordance with New York State Highway Specification item No. 400.
B.
New York State item No. 403.17, asphaltic concrete top
course.
(1)
Prior to the installation of the top course and in order
to ensure smooth wearing surface, all bird baths, washboards, etc., if present
in the base course, shall be removed by hand paving and leveling using top
course mix.
(2)
The wearing surface shall consist of one course of asphaltic concrete of a minimum compacted finished depth of two inches of the New York State Highway Specification item No. 403.17 laid upon a properly prepared base course as described under Subsection A. Said wearing course shall be applied a minimum of six months after the base course has been installed in order to permit stabilization. In addition, the wearing course shall not be installed until written permission is granted by the Town Engineer.
(3)
The asphalt and the method of preparing and mixing shall
be in accordance with New York State Highway Specification item No. 400.
C.
Placing and compaction.
(1)
The material shall be uniformly spread with a mechanical
spreader where feasible. When the material is to be placed in restricted areas
or the quantity is too small to warrant the use of such equipment, it may
be spread with nonmechanical spreaders, as directed by the Town Engineer,
but extreme care shall be exercised to keep segregation to a minimum. The
temperature of the material when placed shall not be less than 265º F.
nor greater than 300º F. for base course and 260º F. to 300º
F. for wearing course.
(2)
No paving will be permitted after October 31 of each
year except with the written permission of the Town Engineer. Under no circumstances
shall material be placed when the surface temperatures are below 40º
F., or the weather inclement.
(3)
Rolling shall take place immediately after placing, and
when the rolling does not cause undue displacement, cracking or shoving the
rolling shall continue until satisfactory compaction has been achieved. The
roller shall have a minimum weight of 10 tons. Hand tamping or mechanical
compacting equipment shall be used on all areas inaccessible to rollers.
(4)
After rolling, the course shall be tested with a straight
edge, 16 feet in length, and any depression over 1/4 inch in depth shall be
satisfactorily eliminated.
A.
Asphalt curbs. Asphalt concrete curbing of cross sections
as indicated in standard sections shall be required by the Town Engineer at
locations shown on the drawings and/or as determined in the field. The general
composition of the mix shall meet the following specifications:
(1)
Mineral aggregate shall be graded and combined to meet
the following limits by weight:
|
Sieve Size
|
Percent Passing
| |
|---|---|---|
|
1/2-inch
|
100%
| |
|
1/4-inch
|
90% to 100%
| |
|
1/8-inch
|
80% to 100%
| |
|
No. 20
|
30% to 70%
| |
|
No. 40
|
15% to 45%
| |
|
No. 80
|
5% to 23%
| |
|
No. 200
|
2% to 10%
|
(2)
The fraction actually retained between any two consecutive
sieves shall be not less than 4%. The proportion of the asphalt to total mixture
by weight shall be 6/8.5%. Temperatures shall be so controlled that the temperature
of the asphalt cement shall not exceed 325º F. and that of the aggregate
at the dryer outlet shall be between 200º F. and 350º F. The temperature
of the mixture as it is dumped from the mixture shall be between 280º
F. and 325º F.
(3)
Prior to the installation of the curbing, the surface
of the pavement where the asphaltic curbing is to be constructed shall have
been cleaned of all loose and foreign material. The surface shall be perfectly
dry and cleaned at the time the mix is placed and shall be coated with an
R.C.-2 or other approved bitumen just before the arrival of the mixture.
(4)
After completion of the installation of the curbing,
traffic shall be kept at a safe distance from the curb for a period of not
less than 48 hours, or as otherwise required by the Town Engineer.
B.
Concrete curbs. Concrete curbs shall be installed when
directed by the town authority or as directed by the Town Engineer. Concrete
curbs, dropped curbs and curb returns shall be constructed in accordance with
New York State item No. 609-3.03, concrete curb, of New York State Department
of Transportation Standard Specifications of January 2, 1981, with the following
amendments:
(1)
(2)
Expansion joints shall be located 30 to 40 feet on center
and shall be formed with premolded bituminous joint filler, 3/4 inch in width.
(3)
Contracting joints shall be formed at fifteen- to twenty-foot
intervals by means of one-fourth-inch thick steel separators which shall be
removed as soon as practicable after the setting of the concrete.
(4)
In no case will dusting with dry material to absorb surface
water be permitted.
(5)
Immediately after placing or finishing, the concrete
surface shall be protected from loss of moisture, rapid temperature change
and mechanical injury for at least three days after placement. After all free
water has disappeared from the surface, uniformly spray a liquid white pigmented
membrane forming compound on all exposed surfaces conforming to AASHTO M-173
or ASTM D-1190. The curing compound will not be applied during rainfall. When
the concrete is placed in cold weather and the temperature is below 35º
F., straw, hay, insulated curing blankets or other suitable material is to
be placed to protect the concrete. Any concrete damaged by freezing or frost
action will be removed and replaced at the contractor's expense.
Sidewalks, when required by town authority, shall be either concrete
or asphaltic concrete on a well-compacted, gravel base. Width of sidewalk
shall be a minimum of five feet with a slope of 1/4 inch to the foot toward
the curb or gutter of the roadway.
A.
Concrete sidewalks.
(1)
Concrete sidewalk shall consist of a five inch thick
single course of concrete laid on a gravel foundation five inches thick, except
in driveways where the concrete shall be seven inches thick and reinforced
with six-by-six steel fabric No. 6 gauge meeting ASTM Standard A-185. Design
concrete mix shall be as described below.
(2)
Concrete sidewalks shall be built in independent rectangular
slabs approximately six feet long separated by one-fourth-inch joints. At
the juncture of driveways and sidewalks, one-half-inch, premolded bituminous
joints shall be installed.
(3)
The top surface shall be finished to true smooth planes
by troweling and floating, and each rectangular slab shall have edges neatly
rounded with the proper tools. Concrete shall be cured in an approved manner
and the sidewalk shall be protected and kept in first-class condition until
accepted by the town.
(4)
Concrete walks shall be constructed in accordance with
New York State Section 608.01, Subsection 608-3.01 of the New York State Department
of Transportation Standard Specifications dated January 2, 1981.
(5)
(6)
All concrete surfaces shall be brought to the proper
grades by means of a strike board. The screeds shall then be removed and space
filled with concrete, which is well floated with a wood float, in a manner
that will thoroughly compact it and provide a smooth, even surface.
(7)
All surfaces shall receive the following treatment: after
the water sheen has disappeared, the surface shall be trowelled only enough
to make smooth, followed by a light brushing with a hair brush or other approved
finish to give a nonslip finish.
(8)
Dummy joints shall be provided for all areas through
the use of an approved jointer and edging tool. Depth of joints shall be at
least 1/2 inch. Dummy joints shall be constructed every five feet, and every
20 feet an expansion joint shall replace a dummy joint.
(9)
All expansion joints shall be sealed to within 1/4 inch
of the surface with a pot-poured bituminous rubber compound equal to Para-Plastic,
as manufactured by Serviced Products Company.
(10)
Jointing compound shall be poured until all curing compound
has been completely removed,
B.
Concrete aprons (driveways).
(1)
Concrete aprons shall be constructed as per detail and
at locations called for under drawings or as directed by the Town Engineer.
Concrete aprons shall be constructed in accordance with New York State Section
608.01, Subsection 608-3.01 of the New York State Department of Transportation
Standard Specifications dated January 2, 1981.
(3)
All concrete surfaces shall be brought to the proper
grades by means of a strike board. The screeds shall then be removed and space
filled with concrete, which is well floated with a wood float, in a manner
that will thoroughly compact it and provide a smooth, even surface.
(4)
All surfaces shall receive the following treatment: after
the water sheen has disappeared, the surface shall be troweled only enough
to make smooth, followed by a light brushing with a hair brush or other approved
treatment to give a nonslip finish.
(5)
The requirements for Section 556, Reinforcing Steel for
Concrete Structures, of the New York State Department of Transportation Standard
Specifications for Construction and Materials, dated January 3, 1978, will
apply.
(6)
Dummy joints shall be provided for all areas through
the use of an approved jointer and edging tool. Depth of the joints shall
be at least 1/2 inch. Dummy joints shall be constructed every five feet and
at every 20 feet, an expansion joint shall replace a dummy joint.
(7)
All expansion joints shall be sealed to within 1/4 inch
of the surface with a pot-poured bituminous rubber compound equal to Para-Plastic,
as manufactured by Serviced Products Company.
(8)
Joint compound shall be poured until all curing compound
has been completely removed.
(9)
Asphaltic concrete sidewalks shall consist of a wearing
course 1 1/2 inches compacted thickness and a binder course 2 1/2
inches compacted thickness. All materials and installation to meet requirements
of New York State Highway Specification Nos. 403.16 and 403.13. The foundation
course for the above stated surfacing shall be six inches compacted thickness
of New York State Highway Specifications No. 304.05 and shall meet requirements
as set forth in Section 300 of the New York State Highway Specifications,
Select Fill.
Adequate provisions shall be made to remove surface and subsurface drainage
from the roadway. The developer shall furnish and install all bridges, culverts,
catch basins, inlets, manholes, storm sewers, sub-drains and other drainage
improvements required by the Town Engineer.
A.
Basis for design. Basis for design of drainage improvements
for local drainage areas with small watersheds shall be based on a rainfall
with a return period of 10 years. Where flowing streams, as shown on the Drainage
Basin Plan (a map prepared by Metcalf and Eddy, dated March, 1975) are involved
or where drainage is conveyed past town, county or state roadways, a storm
with a return period of 100 years shall be used. The one-hundred-year storm
shall be determined using the Soil Conservation Service (SCS) method or approved
equal.
B.
General requirements.
(1)
Catch basins, inlets or storm manholes shall be located
on all changes in direction of storm drains and at intervals not to exceed
300 feet on all pipe lines 24 inches in diameter or smaller, unless otherwise
approved by the Town Engineer.
(2)
Gutters may carry flow for a maximum distance of approximately
600 feet and must then discharge into a storm sewer or laterally off the roadway
into an existing waterway, unless otherwise directed by the Town Engineer.
(3)
Grades over 10% shall require other than asphaltic concrete-type
gutters where no underground storm drainage is employed, unless, in the opinion
of the Town Engineer, the quantity of flow is insufficient to cause damage
to the gutter pavement.
C.
Detention basins. When detention basins are required
by the approving authority, the design of said structures shall be, as follows:
(1)
The runoff allowed shall be determined by using the SCS
methodology. The one-hundred-year storm return frequency shall be used for
determining the existing future peak discharges. The volume of storage shall
be computed by routing the future flows through the proposed detention basin
and limiting the discharge to that of the existing flows. The one-year, two-year,
five-year, ten-year, twenty-five-year, fifty-year and one-hundred-year storms
shall be routed through the new system.
(2)
In the case of subdividers, utilization of a portion
of land set aside for drainage control, conservation or park land may be permitted
by the Planning or Town Boards, depending on jurisdiction. Park lands shall
only be used if such use will not hamper the intended park use in fair weather.
In the case of industrial or commercial development, said developer shall
provide sufficient detention volume based upon utilization of subsurface storage,
roof storage or sufficient area of parking field to provide the correct storage
basin. However, the parking area shall only be used to provide storage volume
required beyond the fifty-year storm.
(3)
All areas in residential development established for
detention basing or drainage control, except conservation or drainage easements,
shall be deeded to the town by the developer. This deeding shall in no way
relieve the developer from the construction, maintenance and final rehabilitation
of the basin for acceptance by the town after all other items of improvements
are accepted.
(4)
The above requirements also hold for developments under
clustering, density or any other standards which may leave open space in the
hands of a neighborhood association, but the roads pass in title to the town,
except in the case of condominiums in which case the condominiums will own
and maintain the roads and drainage facilities.
(5)
Where the development has lands held by a central private
owner, landlord, etc., and the roads and/or parking areas are in such central
private ownership the drainage facility and its operation, maintenance, etc.,
shall remain a responsibility of said owner or landlord.
(6)
All detention basins shall be adequately fenced or otherwise
protected as ordered by the Town Engineer where necessary for the protection
of the public.
(7)
In all new projects, sediment basins shall be constructed
prior to any other construction in said project and shall serve to confine
on the site material eroded as a result project operations. Sediment basins
shall fulfill all the requirements of the approved Erosion and Sediment Control
Plan, in addition to those additional requirements hereinafter specified.
Chapter 165, Erosion and Sediment Control, shall also apply where applicable.
(8)
Cash escrow; liability and property insurance.
(a)
A cash escrow in an amount as determined by the Town
Engineer and separated from any other cash or bond amount shall be posted
with the Town of Yorktown by the project developer to insure construction
of this sediment basin and maintenance of such basin until such time as the
project is completed.
(b)
Prior to any construction, the developer shall enter
into an agreement with the Town of Yorktown granting permission to the personnel
of the Town of Yorktown or private contractor engaged by the Town of Yorktown
to enter upon the developer's property for the purpose of constructing or
maintaining said basin(s). The Town of Yorktown or its designated contractor
shall maintain the necessary liability and property insurance to cover the
period of this construction. This procedure shall be followed in the event
that the developer does not proceed with the required facility after the expiration
of a five-day notice from the Town Engineer, and after the Town Engineer has
been authorized by the Town Board to proceed with this action.
(c)
Said escrow funds shall also be utilized to rectify any
downstream filtration or other stream damage as a result of the developer's
operation.
(9)
Upon completion of the project, if the approved erosion
and sediment control plan allowed stormwater detention basins to be utilized
as sediment basins, said basins shall be thoroughly cleaned to the originally
approved grades and adequately seeded to provide stabilized slopes and bottoms
for erosion and dust control.
D.
Catch basins.
(1)
A three-inch structural masonry brick chimney shall be
placed beneath each frame for future adjustments.
(2)
Frames shall be set one inch below finished grade as
measured at a distance 1 1/2 inches in either direction along the gutter
line.
(3)
The catch basins shall be precast concrete as manufactured
by the Fort Miller Co., Inc., or approved equal. All concrete construction
shall conform to the requirements of NYSDOT Specifications Section 555, Structural
Concrete.
(4)
Precast concrete catch basins shall be cast with 4000
psi concrete (at 28 days). The steel shall conform to the requirements of
ASTM A615-A497. Air entrainment shall be a minimum of 5%. The loading shall
conform to AASHTO H-20 with 30% impact and equivalent soil pressure of 130
pounds per cubic foot.
(5)
Steps. All catch basins shall be constructed with aluminum
steps as manufactured by Alcoa Aluminum, Type No. 16207B or approved equal.
Steps shall be set 12 inches on center.
(6)
All pipe shall be cut flush with the interior walls of
the catch basins,
(7)
All catch basins shall be placed on a six-inch foundation
of three-fourths-inch washed crushed stone.
(8)
The catch basin frames and grates shall be cast-iron
Type 2541 Campbell Foundry or approved equal.
(9)
The cast-iron frames shall be set in a bed of mortar.
(10)
Catch basins shall have an 18 inch sump.
E.
Manholes.
(1)
Concrete for the base slab, if required, shall be formed
and shall be 1:2:4 concrete placed in accordance with requirements of NYSDOT
Specifications Section 555, Structural concrete.
(2)
Bricks for chimney adjustments shall conform with ASTM
Specifications. C-12 grade N. A. Brick and Masonry units shall be laid in
a full bed of mortar composed of one part Portland cement and two parts mortar
sand, by a competent mason in a workmanlike manner.
(3)
The drainage manholes shall be precast concrete as manufactured
by the Fort Miller Co., Inc., or approved equal. All concrete construction
shall conform to the requirements of NYSDOT Specifications Section 555, Structural
Concrete.
(4)
Precast concrete drain manholes shall be cast with 4,000
pounds per square inch (psi) concrete (at 28 days). The steel shall conform
to requirements of ASTM A615-A497. Air entrainment shall be a minimum of 5%.
The loading shall conform to AASHTO H-20 with 30% impact and equivalent soil
pressure of 130 pounds per cubic foot.
(5)
Steps. All drain manholes shall be constructed with aluminum
steps as manufactured by Alcoa Aluminum, Type No. 16207B or approved equal.
They shall be placed 12 inches on center. The steps shall have hooked ends.
(6)
All pipe shall be cut flush with the interior walls of
the drain manholes.
(7)
All drain manholes shall be placed on a six-inch foundation
of three-fourths-inch washed crushed stone.
(8)
The drain manhole frames and covers shall be cast-iron
Type 1203 Campbell Foundry or equal. The cover shall be entitled "drain."
(9)
The cast-iron frames shall be set in a bed of mortar.
(11)
A three-inch structural brick chimney shall be placed
beneath each flame for future adjustments.
(12)
Frames shall be set one inch below finished grade as
measured at a distance of 1 1/2 inches in all directions.
F.
Storm drains and culverts.
(1)
Pipes of the required sizes shall be located where necessary
to provide adequate drainage for the roadway.
(2)
In areas where there is bleeding of groundwater, the
developer shall install curtain drains to protect the road. In areas where
the road cut exceeds 30 inches, curtain drains shall be required.
(4)
All pipe shall meet the approval of the Town Engineer
before construction. The developer shall submit to the Town Engineer a certified
certificate from the manufacturers setting forth the type and size of pipe
to be used. If corrugated metal pipe is used, the manufacturer's certificate
shall specify gauge and coatings in addition to type and size.
(5)
Drainage pipes shall have a minimum inside diameter of
15 inches with a minimum cover of 24 inches to finished grade, unless otherwise
specified by the Town Engineer. Culvert grades shall, if possible, lie between
2% and 4% with a minimum of 1%. Inverts shall be 42 inches below finished
grade. A reinforced concrete pipe shall be installed in areas where it is
necessary to install a storm drain at a slope equal to or greater than 15%.
(6)
Concrete pipe shall be bedded in an earth foundation
which is firm, but slightly yielding, and carefully shaped to fit the lower
part of the pipe.
(7)
Bell and spigot reinforced concrete pipe shall have joints
sealed with flexible watertight elastomeric gaskets.
(8)
Culverts for stream crossings shall be reinforced concrete.
(9)
Pipe specifications.
(a)
Aluminized steel Type 2 corrugated steel pipe.
[1]
Scope. This specification covers aluminum coated (Armco
Aluminized Steel Type 2) corrugated steel pipe and pipe-arch for culverts
and sewers. Pipe shall be manufactured in accordance with AASHTO M-274-801.
[2]
Materials:
[a]
The coils from which the pipe is produced shall be coated
with one ounce per foot of commercially pure aluminum known as "Armco Aluminized
Steel Type 2." The weight of coating (total for both sides, ounces per foot)
shall conform to the following requirements:
[b]
Minimum check limit, triple-spot test: 1.00.
[c]
Minimum check limit, single-spot test: 0.90.
[d]
Aluminum bath analysis. The bath shall be produced from
commercially pure aluminum, and the bath analysis shall conform to the limits
given below:
|
Element
|
Percentage
| |
|---|---|---|
|
Iron (maximum)
|
3.0%
| |
|
Silicon (maximum)
|
0.35%
| |
|
Aluminum (minimum)
|
96.0%
| |
|
Magnesium (maximum)
|
0.50%
|
[e]
Sheet material supplied under this specification shall
meet the applicable requirements of the latest revision of ASTM Specification
A-525, unless otherwise specified herein.
[3]
Fabrication:
[a]
Pipe may be furnished circular or as a pipe-arch shape
as requested by the purchaser and shall be fabricated with helical corrugations
and a continuous weld or lock seam extending from end to end of each length
of pipe. Each end of each pipe shall have two annular corrugations reformed
to permit joining with Hugger Bands.
[b]
The corrugation shall have a pitch of 2 2/3 inch
and a depth of 1/2 inch, or a three inch pitch and one inch depth, or 125
millimeter pitch and 25 millimeter depth, as called for. The following shall
be dimensions for corrugations:
[c]
Nominal diameter of finished pipe: 12 to 21 inches.
[d]
Minimum pitch: 1 7/8 inches.
[e]
Maximum pitch: 2 3/4 inches.
[f]
Minimum depth: 7/16 inches.
[g]
Tolerances on thickness diameter, length of pipe and
corrugation size shall be as specified in the current AASHTO M-36 specifications
for CSP or as designated below:
[h]
Gauge. All steel aluminized pipe to be of the following
gauges unless otherwise stated.
|
Pipe Diameter
(inches)
|
Standard Gauge
|
Decimal Thickness
(inches)
| |
|---|---|---|---|
|
12 to 21
|
16 gauge
|
.064
| |
|
24
|
16 gauge
|
.064
| |
|
27 to 36
|
14 gauge
|
.079
|
[4]
Pipe-arch shape. Structures furnished as a pipe-arch
shape shall meet the dimensions per AASHTO M-36.
[5]
Coupling bands:
[a]
The field joints in corrugated steel aluminized pipe
shall be made with steel aluminized band couplers of the same metal as that
used in the pipe. Band couplers shall be seven inches wide for pipe diameters
six inches through 18 inches, and 12 inches wide for pipe diameters 21 inches
through 48 inches. Band couplers may be two gauges lighter than that of the
pipe.
[b]
If a one piece band coupler is used, it shall be fastened
with two galvanized steel bolts on a seven-inch band and three bolts on a
twelve-inch band. If a seven-inch two-piece coupler is used, it shall be fastened
with four galvanized steel bolts.
[c]
One-half inch diameter galvanized steel bolts shall be
used on steel aluminized metal coupling bands for pipe sizes 12 inches in
diameter and larger.
[6]
Perforations; perforated C.M.P. Perforations shall be
arranged in two groups of longitudinal rows placed symmetrically on either
side of an unperforated segment corresponding to the flow line of the pipe.
Within each group, the rows of perforations shall be spaced circumferentially
approximately one inch center to center, and in each row the perforations
shall be located either on the inside crests or on the neutral axes of all
corrugations, except that perforations are not required within four inches
of each end of each length of pipe or in the corrugations where seams are
located. The perforations shall have a diameter of not less than 1/4 inch
and not more than 3/8 inch.
[7]
Minimum depth. All steel aluminized curtain drain pipe
shall be placed a distance of not less than two feet from the finished grade
surface.
(10)
Pipe installation for and aluminized steel type.
(a)
The width of the trench in which the pipe is placed shall
be a minimum of two times greater than the diameter of the pipe to ensure
proper alignment of the pipe. The side walls of the trenches should be practically
vertical where possible.
(b)
A minimum six-inch bed of three-fourths-inch washed crushed
stone shall be placed beneath all pipe used as underdrain or curtain drain.
(c)
Placement of pipe. Proper facilities shall be furnished
for lowering the pipe into the trench. The pipe shall not be thrown from the
truck or into the trench. The pipe shall be laid carefully and true to the
lines and grades as shown on the approved plans. The connecting bands of C.M.P.
shall be placed with the clamping angles and bolts at the top of the pipe.
A gap greater than one inch shall not be permitted between ends of the pipe
at clamping points. All pipe shall be cut flush with interior walls of all
catch basins and drain manholes and the walls patched neatly and sealed tightly
around the pipe with mortar.
(d)
If soft, unstable material is encountered at the bottom
trench elevation, it shall be excavated to a grade suitable to the Town Engineer
and backfilled with three-fourths-inch washed crushed stone to provide a stable
foundation. If, however, the trench bed is solid, dry and stable, the pipe
may be placed directly on the existing subsoil for solid (nonperforated) pipes
only.
(e)
If solid rock is discovered in the trench line, it shall
be excavated to at least six inches below the proposed invert line and a minimum
of six inches all around. The excavation shall then be backfilled three-fourths-inch
washed crushed stone to provide a cushion for the pipe.
(f)
Installation of the drainage system shall start at the
downstream outlet to allow stormwater and groundwater to drain out the trench,
to keep the bottom of the trench as dry as possible during construction.
(g)
Underdrain trenches are to be backfilled with three-fourths-inch
washed crushed stone to within five inches (in shoulders) or 11 inches (in
road beds) of the finished grade.
(h)
All existing drain pipes encountered during the excavation
for the new drain pipes shall be tied into the new system (e.g., footing drains,
yard drains, etc.) (perforated C.M.P. only). However, no pipe shall penetrate
a new pipe.
(i)
The crushed washed stone for the drain will meet the
following gradation:
|
Sieve Size
|
Percent Passing by Weight
| |
|---|---|---|
|
1-inch
|
100%
| |
|
1/2-inch
|
30% to 100%
| |
|
1/4-inch
|
0% to 30%
| |
|
No. 10
|
0% to 10%
| |
|
No. 5
|
0% to 5%
|
(j)
Provide a synthetic filter material below finished grade
along all trenching as shown on the detail sheet.
[1]
The material shall be a woven polyproplene mesh, with
an equivalent opening size (EOS) of the United States Standard Sieve No. 70
(0.210 mm). The mesh shall have a percent of open area of 25% plus or minus
2%.
[2]
The mesh shall be placed five inches (in shoulders) or
11 inches (in road beds) below the finished grade of stone. The mesh will
be placed to run four inches up each side of the trench. The mesh shall be
inspected for tears and runs prior to placement. Damaged sections in place
shall be cut out and replaced with appropriate overlaps.
[3]
When additional lengths of material are placed, same
shall overlap previously laid material by a minimum of 16 inches.
(k)
Backfill material; nonperforated pipe.
[1]
Nonperforated pipe installed in the shoulder of the road
shall be backfilled with suitable excavated material from the project. If
none of the material is suitable, clean suitable fill shall be provided as
required by the Town Engineer. The backfilled material will be brought to
five inches of finished grade.
[2]
Nonperforated pipe installed in the bed of the road shall
be backfilled with NYSDOT item No. 304.05. The backfill material shall be
placed to five inches of finished pavement surface.
[3]
All backfilled material shall be compacted with an approved
mechanical tamper in lifts not to exceed eight inches.
[4]
A controlled density fill (CDF) such as K-crete may be
used as a substitute to the NYSDOT item No. 304.05 used for backfill of pipes
within town roads. The K-crete shall attain a minimum compressive strength
at 50 psi after 28 days and an allowable minimum compressive bearing strength
of 5,000 pounds per square foot (psf). The K-crete shall be placed in a fluid
form and uniform vertical lifts. The backfilled trench shall not be opened
to the traffic for a minimum of 24 hours after being installed.
G.
Headwalls and rip-rap. The natural, excavated and embankment
surface of the roadway adjacent to both ends of all culverts shall be protected
from erosion or displacement by precast concrete headwalls as shown on the
standard sections, unless terminated by catch basins or other drainage structures
approved by town authority. If required, in the opinion of the Town Engineer,
wing-walls shall be included in the headwall design. The upstream and downstream
areas at all headwalls shall be provided with a dumped rip-rap stone of irregular
shapes to dissipate the energy of the flowing stormwaters. The width of the
rip-rap pad shall be equal to the length of the pad plus the width of the
pipe diameter. The length shall be determined by using figures 23.4 and 23.5
of the Westchester County Best Management Practices Manual Series dated June
1981.
A.
All earth surfaces of slopes and disturbed areas related
in any way to roads being constructed shall be covered with a minimum of four
inches of topsoil and seeded. Work shall be performed in accordance with item
No. 610 of the State Highway Specifications.
B.
Topsoil shall be stripped from the road area and stockpiled
for this purpose. If insufficient topsoil is not available, it shall be imported.
C.
Seed shall be placed at a rate of 150 pounds per acre
in such a manner and of such consistency to produce a hardy grass that will
produce a turf which will stabilize the slope.
D.
All work and materials used under this section shall
meet the approval of the Town Engineer.
Guide rail may be of the corrugated-beam- or the box-beam-type. The
railing chosen shall be that which permits the greatest deflection without
exceeding the allowable deflection distance.
A.
Corrugated railing shall consist of 12 gauge corrugated
W-beams connected to a four-by-six-inch beam by a four-by-six-inch spacer
block set 27 to 30 inches above grade, meeting the requirements of the current
NYSDOT Standard Specifications for Construction and Materials, Sections 606
and 710.
B.
Box beam railing shall consist of six-by-six-by-three-sixteenths-inch
steel ASTM A-36 seamless structural tubing. Posts shall be item No. 315.7
beams and shall be spaced either six feet or three feet apart, depending on
the deflection design. The installation and materials shall conform to Section
606 and 710 of the current NYSDOT Standard Specifications for Construction
and Materials.
C.
End sections (approach and end treatments) shall be placed
in such a manner so as not to be a hazard. The end sections shall be flared
from the roadway. The end sections shall also be sloped to provide additional
safety for vehicles striking them, and they shall be anchored below ground
to a concrete dead-man to give stability to adjoining sections.
Road signs shall be installed at all street intersections as shown on
the approved plan or as directed by the Superintendent of Highways and Town
Engineer. Style and design of signs shall be of standard construction as required
by the Town Engineer.
In the cases of new roads under construction still under the ownership
of the developer, but after placement of the binder course, and existing roads
(for which a street opening permit has been obtained from the Highway Superintendent),
repair to or installation of drains or any underground utility line beneath
the roadbed shall be followed by backfilling the trench with NYSDOT item No.
304.05 to the top of the existing subgrade. Lifts shall not exceed 12 inches
uncompacted. Approved mechanical tampers shall be utilized.
A.
All construction is to be done in accordance with this chapter and Chapter 195, Land Development.
B.
Permanent survey monuments tied to the New York State
Coordinate System (NAD 83) shall be located where specified by the Town Engineer.
C.
Bench marks using USGS datum shall be located on the
northwest nut of the top flange of fire hydrants where specified by the Town
Engineer.
D.
Location of gas and water valves, electric and telephone
poles are to be determined by proper authorities and approved as to location
by the Town Engineer.
E.
Each dwelling constructed hereon shall be of such an
elevation that the ground will slope away from it in all directions.
F.
Roof leaders and footing drains shall empty into curtain
drains and other town storm drainage systems wherever possible. On plots where
this is not possible, then said drain shall empty on the surface of the property
in question a minimum distance of 20 feet from the back of curb. Elevation
of footings shall be adjusted accordingly to permit proper drainage. Under
no circumstances shall the discharge of groundwater or stormwater, either
by gravity or by pumping, be discharged to any sanitary sewer system. In some
circumstances, it is impossible to provide a free discharge on the property
in question. The discharge pipe must cross a common lot line in order to have
a free discharge. This will be acceptable, provided that a private easement
is filed.
G.
All existing underground drains encountered during construction
of proposed roads are to be connected to proposed drainage improvements.
H.
Interceptor drains are to be installed where required
by the Town Engineer during road construction.
I.
Minimum size of storm drains shall be 15 inches in diameter,
reinforced concrete, corrugated metal aluminized steel Type 2 or aluminum.
A minimum cover of 24 inches shall be maintained.
J.
All hydrants shall require two coats of electro farrothane,
plastic finish No. 44 red paint. All hydrants shall be Mueller centurions
with six-inch valves.
K.
Street signs shall be extruded aluminum .091 inch thick,
6 3/4 inches high, 30 inches long, green with white letters; heavy-duty
aluminum post caps for 2 3/8 inches outside diameter post; 90º aluminum
bracket with self-locking slots; galvanized tubular sign posts 2 3/8
inches outside diameter by 12 feet long; high-strength sign post (channel-type-green),
12 feet long, three pounds per foot.
L.
All site utility lines shall be placed underground,
M.
No topsoil shall be removed from the site.
N.
Two trees per lot shall be provided by the developer.
O.
Erosion and sedimentation control during construction
shall conform to Westchester County, New York, Best Management Practices Manual
on Construction Related Activities.
P.
Street opening permits from the Yorktown Highway Department
will be required for installations and driveway connections.
Q.
All trench openings in town roads will be backfilled
with either K-crete and two inches of asphaltic concrete top or compacted
item No. 4 and three inches of asphaltic concrete binder and two inches of
asphaltic concrete top (see detail).
R.
Town Engineering Department shall be notified 48 hours
before construction is started.
A.
Sanitary sewers are to be of SDR 35 PVC (or heavier,
if required by the Town Engineer due to loading conditions).
B.
Cement lined cast-iron Tyton joint Class 52 pipe shall
be used at all stream crossings for a distance of 100 feet on either side
and encased in concrete under stream beds and into banks on either side a
distance of 10 feet.
C.
Sanitary manholes shall be precast in accordance with
approved standards and shall be spaced a maximum of 300 feet on straight runs
and installed at every change in alignment and difference in elevation of
incoming and outgoing sewers. Manhole positioning shall be as to prevent the
entrance of surface water during storms.
D.
All building sewer connections shall have a cleanout
installed at the property line and/or easement line at time of construction.
E.
Leakage allowance shall be a maximum of 100 gallons per
24 hours per inch of diameter per mile of pipe.
F.
Infiltration, exfiltration and visual tests by means
of light flashing between manholes shall be as per requirements of the Town
Engineer. No tests shall be made until two weeks after backfilling of sanitary
sewers or longer if conditions, in the opinion of the Town Engineer, warrant
it.
G.
All house laterals shall be installed by plumbers, licensed in the Town of Yorktown in accordance with requirements set forth in Chapter 240, Sewers, adopted December 21, 1982. All work shall be inspected before backfilling. Failure to abide by this notice shall result in delay of issuance of certificate of occupancy until work is uncovered and inspected.
H.
All pipe shall be bedded (cushioned) on a minimum of
a six-inch thick layer of three-fourths-inch crushed stone. Additionally,
the three-fourths-inch crushed stone shall be placed the full height of the
pipe zone (haunching to spring line of the pipe thence to the crown of the
pipe).
I.
Sanitary sewer construction shall meet all sewer construction specifications for the Town of Yorktown (Chapter 240, Sewers).
J.
Sewer force main shall be Class 52 cement-lined ductile
iron pipe, except at manholes where Class 56 is required for grooved fittings.
The above construction specifications are detailed on twenty-four-by-thirty-six-inch
sheets and are available from the Town Engineer's office.
