1.1
Description of Work.
A.
The work consists of furnishing and installing a storm drainage system
including precast concrete drain manholes, catch basins, and drop
inlets with accessories, pipe and fittings, jointing, excavation and
backfill, bedding material, and all other related and appurtenant
work complete in place and in accordance with the requirements set
forth, or as directed.
1.2
Special Requirements.
A.
All Approvals and Permits as set forth in the Town of New Shoreham
Ordinance, including Approval from the Departments of Environmental
Management and Coastal Resources Management, must be obtained prior
to construction of a Storm Drainage System.
B.
The New Shoreham Public Works Department shall be notified 48 hours
in advance to inspect the construction.
1.3
Submittals.
A.
General. All submittals shall be submitted to the New Shoreham Director
of Public Works, P.O. Drawer 220, Block Island, Rhode Island 02807.
B.
Contract Drawings. Submit three sets of drawings of proposed sanitary
sewage system for review.
C.
Record Drawings. At completion of project, submit record drawings
of installed storm drainage piping showing a minimum of three ties
from permanent installations such as poles, hydrants, etc., for manholes
and catch basins.
2.1
Pipe.
A.
Polyvinyl Chloride Pipe (six inches - 15 inches) and Fittings. Polyvinyl
chloride (PVC) pipe and fitting shall be in accordance with the latest
issue of ASTM D3034, SDR35 and applicable documents. The PVC pipe
and fittings shall be composed of clean, virgin class 12364-C compounds
conforming to ASTM D1784 and shall be bell and spigot with rubber
ring joints. The bell shall consist of an integral wall section with
a solid cross section rubber ring securely locked in place to prevent
dislocation of the ring. Standard lengths shall be 20 feet and 12.5
feet, plus or minus one inch. Minimum "pipe stiffness": at 5% deflection
shall be 46 for all sizes when tested in accordance with ASTM Designation
D2412, external loading properties of plastic pipe by parallel-plat
loading. All fittings and accessories shall be manufactured and furnished
by the pipe supplier and have bell and/or spigot configurations compatible
with that of the pipe fittings and shall be of the same strength and
quality as the pipe.
B.
Polyvinyl Chloride Pipe (greater than 15 inches) and Fittings. Polyvinyl
chloride (PVC) pipe and fittings shall be in accordance with the latest
issue of ASTM F679. The PVC pipe and fittings shall be composed of
clean, virgin, Class 12454C or 13364C compounds and shall be bell
and spigot with rubber ring joints. The bell shall consist of integral
wall section with a solid cross section rubber ring. Standard lengths
shall be 13 feet plus or minus one inch. Minimum "pipe stiffness":
at 7 1/2% deflection shall be 46 for all sizes when tested in
accordance with ASTM Designation D2412. All fittings and accessories
shall be as manufactured and furnished by the pipe supplier and have
bell and/or spigot configurations compatible with that of the pipe
fittings and shall be of the same strength and quality as the pipe.
C.
Ductile Iron Pipe and Fittings. Ductile iron pipe shall be furnished
in accordance with ANSI Designation A21.51. The ductile iron pipe
shall be thickness Class 52. Pipes shall have normal laying lengths
of at least 18 feet. In addition, each length of pipe shall be cement
lined and receive a factory applied interior and exterior coating
of Kopper's Bitumastic Super Service Black or an approved coating
of equal specifications in accordance with ANSI Designation A21.4.
Ductile iron pipe shall be push-on type of joint which employs rubber
gasket. Joints shall be in accordance with the latest ANSI standard
for "Rubber Gasket joints for Ductile Iron Pressure Pipe and Fittings",
Designation A21.11. Fittings shall be in accordance with ANSI 23.53
with mechanical joints. The fittings shall be coated inside and outside
with a bituminous asphalt paint.
D.
Polyethylene Pipe. Polyethylene pipe and fittings shall be manufactured
from high density polyethylene resin compound which shall meet the
requirements of Type III, Class C, Category 5, Grade P34 per ASTM
1248.
E.
Bituminous Coated Corrugated Metal Pipe. Bituminous Coated corrugated
pipe shall conform to the requirements of AASHO M-36. Pipe shall be
manufactured of galvanized sheet gauge No. 12. Pipe and coupling bands
shall be fully coated with bitumastic material as specified for Type
C, in accordance with AASHO M-190. Coupling bands shall be manufactured
of galvanized sheet gauge No. 14. Special sections such as fittings,
elbows and flared end sections shall be manufactured from galvanized
sheet gauge No. 12 to conform to AASHO M-36 and AASHO M-190.
F.
Reinforced Concrete Pipe. Reinforced concrete pipe and flared end
sections shall conform to the requirements of ASTM C-76, ASTM C-655,
and AASHO M-170.
G.
Perforated Polyvinyl Chloride Pipe. Perforated polyvinyl chloride
(PVC) pipe shall conform to ASTM D-3034, SDR 35. Perforations shall
consist of 2 rows of 15 mm holes positioned at 120° radially on
the pipe and spaced to provide a minimum total cross-sectional hole
area of 1933 mm2 per meter of length. Pipe
shall be supplied with friction-fit bell ends.
H.
Porous Concrete Pipe. The porous concrete pipe shall conform to the
requirements of ASTM C-654 and AASHTO M-176.
2.2
Precast Concrete Drain Manholes and Catch Basins.
A.
Precast Concrete Drain Manholes. Manhole bases, risers, eccentric
cone and flat-slab-top shall consist of precast reinforced concrete
manufactured in accordance with ASTM C-478 and be designed for H20
wheel loading.
The horizontal joints between sections shall be sealed using
flexible butyl resin sealant and shall conform to Federal Specifications
SS-S-210A and AASHTO M-198B.
B.
Precast Concrete Catch Basins. Base, riser sections, and flat-slab-top
shall consist of precast reinforced concrete conforming to ASTM C-478
and be designed for H20 wheel loading. The horizontal joints between
sections shall be sealed using a flexible butyl resin sealant and
shall conform to Federal Specifications SS-S-210A and AASHTO M-198B.
C.
Pipe Connectors. Resilient complying with ASTM C923. For pipes up
to 24 inches, the pipe connectors shall be Kor-N-Seal and for pipe
over 24 inches, the pipe connector shall be A-Lok or equal.
D.
Manhole Steps. Manhole steps shall be of safety type and shall be
cast into the units during process of manufacture. Steps shall be
steel reinforced copolymer polypropylene plastic step conforming to
ASTM C478 or aluminum forgings alloy 6016, Temper T-16 and those parts
which are embedded in the concrete shall be thoroughly cleaned and
given a heavy coating of zinc chromate or other approved paint. In
addition, steps shall conform to OSHA regulations.
E.
Frames, Covers and Grates. Cast-iron manhole frames, covers and grates
shall conform to the requirements of AASHTO M105. Castings shall be
true to pattern and free from flaws. The bearing surfaces of the frames,
cover and grates shall be machined so as to give continuous contact
through their circumference and shall be non-rocking. The design on
the cover shall be diamond with the word "DRAIN" lettering cast into
the top surface.
F.
Brick Masonry and Mortar Cement. Brick shall be Grade SM, ASTM C-32
or Grade SM, AASHTO M-91. All brick shall be common hard rubber clay
brick and shall be uniform and regular in shape and size. Mortar cement
for masonry shall conform to ASTM Designation C-144. The mortar cement
shall be composed of one part masonry cement to 2 1/2 parts sand
with water not to exceed 4.1 gallons per 70 pound bag of masonry cement.
If using Portland cement, lime putty may be added in such amounts
that the hydrated lime does not exceed 15% by weight of cement.
2.3
Gravel base.
A.
Gravel shall be free of foreign material such as loam, silt, clay
and vegetable matter and meet the following requirements:
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Passing 1 1/4-inch sieve
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100%
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Passing 1/4-inch sieve
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30% - 65%
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Passing No. 40
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5% - 50%
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Passing No. 100
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0% - 10%
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2.4
Bedding Material.
A.
The bedding material shall be crushed stone consisting of durable
crushed rock or durable crushed gravel stone, free from ice, snow,
sand, clay, loam or other deleterious material. The crushed stone
shall conform to the requirements of 100% passing the 3/4 inch screen,
10% to 50% passing the one-half-inch screen, 0% to 20% passing the
three-eighths-inch screen and 0% to 5% passing the number four sieve.
2.5
Sand Blanket.
A.
The sand shall be free from ice, snow, roots, sod, rubbish, and other
deleterious or organic matter. The sand blanket shall conform to the
requirements of 100% passing the 1/2 inch screen, 85% - 100% passing
the 3/8 inch screen, 60% - 85% passing the number #4 sieve, 35% -
60% passing the number 16 sieve, 10% - 35% passing the number #50
sieve and 2% - 10% passing the number #100 sieve.
2.6
Backfill.
A.
Backfill shall be excavated material free-draining clean granular
soil suitable for backfill. Up to 20% of backfill material may be
rock-like materials not to exceed 0.05 cubic feet in volume, nor more
than six inches in length. The backfill shall not contain any debris,
pavement, frozen material, organic matter or peat.
3.1
Inspection.
A.
The New Shoreham Department of Public Works shall be notified prior
to installation of a storm drain system so that inspections can be
made throughout the project.
3.2
Product Handling.
A.
Each product shall be handled into its position in the trench in
such a manner and by such means as the manufacturer recommends as
satisfactory, and these operations will be restricted to those considered
safe for the workmen and such as to cause no injury to the product
or any property.
B.
The contractor will be required to furnish slings, straps, and/or
other devices to provide satisfactory support of the pipe when it
is lifted. Transportation from delivery areas to the trench shall
be restricted to operations which can cause no injury to the product.
The products shall not be dropped from trucks or into the trench.
C.
The contractor shall have on the job site with each crew, all the
proper tools to handle the products being installed. The use of hammer
and chisel or any other method which results in rough edges, chips
and damages, shall be prohibited.
3.3
Excavation and Backfill for Pipes.
A.
The width of the trench shall be held to a minimum consistent with
the space required to permit satisfactory jointing of the pipe and
tamping of the bedding and backfill material under and around the
pipe. In general, the maximum trench width shall be the pipe diameter
plus two feet or a minimum width of three feet, whichever is greater.
If necessary, sheeting and/or shoring shall be used to prevent overcutting
at the level of the top of the pipe and to maintain the trench sides.
The trench bottom should be smooth, level and all large stones or
rocks lying on or protruding from the trench bottom shall be removed.
Over-excavation shall be refilled in six-inch lifts with approved
granular material and compacted to 95% maximum density.
B.
Where unsuitable material is encountered at the trench bottom, the
material shall be excavated to a stable bottom and refilled with compacted
bedding material in six-inch lifts.
C.
Backfill from the centerline of the pipe to the height two feet above
the pipe shall be sand blanket material placed evenly the full width
of the trench and compacted. The remainder of the trench shall be
backfill material and compacted in twelve-inch layers. Cushion and
backfill material shall be compacted to 95% maximum density by tamping
and compacting in layers (one-foot maximum) to achieve the required
compaction.
3.4
Installation of Pipe.
A.
Each pipe length shall be inspected for cracks, defects in coating
or lining, and any other evidences of unsuitability. Before lowering
in place, the pipe shall be struck with a suitable tool to verify
its soundness.
B.
Pipe shall be laid in the dry and at no time shall water in the trench
be permitted to flow into the pipe.
C.
The pipe shall then be laid on the trench bedding as shown in the
trench detail, and the spigot pushed home. Jointing shall be in accordance
with the manufacturer's instructions and appropriate ASTM standards,
and the contractor shall have on hand for each pipe-laying crew, the
necessary tools, gauges, pipe cutters, etc. necessary to install the
pipe in a workmanlike manner. Pipe laying shall proceed upgrade with
spigot ends pointing in the direction of flow.
D.
Blocking under the pipe will not be permitted except where a concrete
cradle is proposed, in which case precast concrete blocks shall be
used.
E.
After the pipe has been set to grade, additional bedding material
shall be placed in six-inch layers up to the spring line of the pipe.
Tamping bars shall be carefully employed to assure compaction of the
bedding under the lower quadrants of the pipe for the full width of
trench excavation.
F.
If a trench box is being used and the trench box is below the spring
line of the pipe, the trench box shall be lifted vertically and the
stone bedding shall be thoroughly compacted to the trench wall. The
trench box shall not be pulled horizontally along the trench.
G.
At any time that work is not in progress, the end of the pipe shall
be suitability closed to prevent the entry of animals, earth, etc.
H.
Unsatisfactory work shall be dug up and re-installed to the satisfaction
of the Department of Public Works.
3.5
Installation of Drain Manholes and Catch Basins.
A.
Bases for all drain manholes and catch basins shall be placed on
a minimum of six inches of compacted bedding material. The excavation
shall be properly dewatered and maintained dry while placing bedding
material and setting the bases. Manholes shall be backfilled evenly
and in layers, maximum one-foot thick, with suitable backfill material
and compacted to achieve 95% maximum density.
B.
Sheeting and/or bracing shall be used when required.
C.
Manhole barrel and cone sections shall be set so as to be vertical
and in true alignment.
D.
Where required for future connections, openings shall be cast in
the manholes at the proper location and shall be sealed with plugs.
E.
The inverts of all drain manholes shall be constructed of brick and
formed in accordance with the details.
F.
Bricks shall be laid in a workmanlike manner, true to line and the
joints shall be carefully struck and pointed on the inside. Bricks
shall be thoroughly wet when laid and each brick shall be laid in
mortar so as to form full bed, end and side joints in one operation.
The outside of the brickwork shall be neatly plastered with 1/2-inch
layer of cement mortar as the work progresses. The brickwork shall
be satisfactorily bonded to the concrete and cast iron frame. No brick
masonry shall be laid in water, or any water allowed to rise on the
brickwork until the masonry has set for at least 24 hours.
G.
All lift holes shall be filled with non-shrinking mortar such as
Quick-Plug prior to backfilling.
3.6
Connections to Existing Drain Manholes.
A.
Connections to existing drain manholes shall be made so as not to
damage the structure. The crown of the new pipe shall be at the same
elevation as the main of the largest existing pipe. The openings shall
be cored and Kor-N-Seal boot shall be installed. The inverts shall
be modified as directed to accommodate flow from the new pipe.
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