B.
Quality assurance.
(1)
Reference standards.
(a)
American National Standards Institute (ANSI).
(b)
American Society for Testing and Materials (ASTM).
[1]
A53, Specification for Pipe, Steel, Black and Hot-Dipped Zinc-Coated,
Welded and Seamless.
[2]
A74, Specification for Cast Iron Soil Pipe and Fittings.
[3]
C425, Specification for Compression Joints for Vitrified Clay
Pipe and Fittings.
[4]
C564, Specification for Rubber Gaskets for Cast Iron Soil Pipe
and Fittings.
[5]
C700, Specification for Vitrified Clay Pipe, Extra Strength,
Standard Strength and Perforated.
[6]
D2241, Specification for Poly (Vinyl Chloride) (PVC) Pressure
Rated Pipe (SDR series).
[7]
D2321, Practice for Underground Installation of Termoplastic
Pipe for Sewers and other Gravity-Flow Applications.
[8]
D3034, Specification for Type PSM Poly (Vinyl Chloride) (PVC)
Sewer Pipe and Fittings.
[9]
D3139, Specification for Joints for Plastic Pressure Pipes Using
Flexible Elastomeric Seals.
[10]
D3212, Specification for Joints for Drain and Sewer Plastic
Pipes Using Flexible Elastomeric Seals.
[11]
F477, Specification for Elastomeric Seals (Gaskets) for Joining
Plastic Pipe.
[12]
F679, Specification for Poly (Vinyl Chloride) (PVC) Large-Diameter
Plastic Gravity Sewer Pipe and Fittings.
(2)
Materials contaminated with gasoline, lubricating oil, liquid or
gaseous fuel, aromatic compounds, paint solvent, paint thinner, or
acid solder will be rejected.
C.
Submittals.
(1)
Certificates. Submit two copies of each manufacturer's certification
attesting that the pipe, pipe fittings, valves, joints, joint gaskets
and lubricants and detectable warning tape meet or exceed specification
requirements.
(2)
Manufacturer's literature. Submit two copies of the manufacturer's
recommendations on installation, handling and storage of materials.
(3)
Details of bypass pumping operation and pump curves.
D.
(Reserved)
E.
Product delivery, storage and handling.
(1)
Delivery and handling.
(a)
Do not place materials on private property without written permission
of the property owner.
(b)
During loading, transporting and unloading, exercise care to
prevent damage to materials.
(c)
Do not drop pipe or fittings. Avoid shock or damage at all times.
(d)
Take measures to prevent damage to the exterior surface or internal
lining of the pipe.
B.
H.
Detectable warning tape. Detectable warning tape shall be metallic
and encased in a protective, high-visibility, green-color-coded inert
plastic jacket that is impervious to all known alkalis, acids, chemical
reagents and solvents found in the soil. Tape width shall be a minimum
of two inches and have the words "Caution Buried Sewer Line Below,"
or similar imprinted. Tape shall be approved by the Engineer prior
to installation.
I.
Valves.
(1)
Plug valves.
(a)
Plug valves shall be of the nonlubricated, eccentric type, and
shall be designed for a working pressure of 175 psi for valves 12
inches and smaller. Valves shall be of round port design. If a rectangular
style design is employed, port area shall be a minimum of 100% of
the corresponding pipe area.
(b)
Valves shall provide tight shut-off with rated pressure from
either direction, where required. The plug valves shall be manufactured
by Dezurik of Sartell, MN, Keystone Valve of Houston, TX, or approved
equal.
(c)
Plug valves shall be furnished with replaceable permanently
lubricated sleeve-type 18-8 stainless steel bearings in the upper
and lower journals. Valve seats shall be nickel with raised surface
completely covered to ensure that the plug face contacts only nickel.
(d)
Manual gear operators shall be totally enclosed worm and gear
type, permanently lubricated. Manual operator components shall withstand,
without damage, a pull of 80 to 200 pounds on the handwheel, with
buried service gear units capable of withstanding input torque on
the operating nut as required by AWWA C504, and AWWA C507. Gear segment
shall be of ductile iron, ASTM A536, Grade 56-45-12 supported on bronze
bushings.
(e)
Plug valves shall be tested in accordance with AWWA C504. The
leakage test shall be applied to the face of the plug tending to unseat
the valve. Certified copies of reports covering proof of design testing
shall be provided to the municipality.
J.
Pump stations.
(1)
New wet wells will be lined with extruded PVC or HDPE liner cast
integral with inside wall of manhole. Acceptable lining systems are
Ameron T-Lok PVC or AGRU Sure Grip HDPE. Engineer shall review shop
drawings for lined wet wells.
(2)
Wet well manhole shall meet the requirements of ASTM C478, six-foot
minimum inside diameter.
(3)
Pumps, enclosure, valving, fittings, fencing, landscaping and electric
service shall be in accordance with Standard Details DT 02610-3 and
DT 02610-4[1] and approved by the Engineer.
[1]
Editor's Note: Said Standard Details are included as an attachment to this chapter.
A.
Preparation.
(2)
Unless otherwise required by the municipality, provide for a minimum
cover of four feet above the top of pipe laid in trenches in nontraffic
areas, and five feet in traffic areas.
(3)
For PVC and cast iron pipe, use AASHTO No. 57 crushed aggregate pipe
bedding. Use select excavated material for ductile iron pipe bedding.
(4)
Provide AASHTO No. 10 crushed aggregate bedding for two-inch diameter
and smaller pressure sewers.
B.
Laying pipe in trenches.
(1)
Give ample notice to the municipality in advance of pipe-laying operations,
minimum 24 hours.
(2)
Maintain no less than three batter boards or their equivalent between
adjoining manholes during pipe-laying operations, or use laser alignment
instruments.
(3)
Lower pipe into trench using handling equipment designed for the
purpose to assure safety of personnel and to avoid damage to pipe.
Do not drop pipe or fittings.
(4)
Lay pipe proceeding upgrade with the bell or groove pointing upstream.
(5)
Lay pipe to a true uniform line with the barrel of the pipe resting
solidly in bedding material throughout its length. Excavate recesses
in bedding material to accommodate joints, fittings and appurtenances.
Do not subject pipe to a blow or shock to achieve solid bearing or
grade.
(6)
Lay each section of pipe in such a manner as to form a close concentric
joint with the adjoining section and to avoid offsets in the flow
line.
(7)
Clean and inspect each section of pipe before joining. Assemble to
provide tight, flexible joints that permit movement caused by expansion,
contraction, and ground movement. Use lubricant recommended by the
pipe and fitting manufacturer for making joints. If unusual joining
resistance is encountered or if the pipe cannot be fully inserted
into the bell, disassemble joint, inspect for damage, reclean joint
components, and reassemble joint.
(8)
Assemble joints in accordance with recommendations of the manufacturer.
(a)
Push-on joints.
[1]
Clean the inside of the bell and the outside of the spigot.
Insert rubber gasket into the bell recess.
[2]
Apply a thin film of gasket lubricant to either the inside of
the gasket or the spigot end of the pipe, or both.
[3]
Insert the spigot end of the pipe into the socket using care
to keep the joint from contacting the ground. Complete the joint by
forcing the plain end to the bottom of the socket. Mark pipe that
is not furnished with a depth mark before assembly to assure that
the spigot is fully inserted.
(b)
Mechanical joints.
[1]
Wash the socket and plain end. Apply a thin film of lubricant.
Slip the gland and gasket over the plain end of the pipe. Apply lubricant
to gasket.
[2]
Insert the plain end of the pipe into the socket and seat the
gasket evenly in the socket.
[3]
Slide the gland into position, insert bolts, and finger-tighten
nuts.
[4]
Bring bolts to uniform tightness. Tighten bolts 180° apart,
alternately.
|
Bolt Size, Inches
|
Torque Required Torque, Foot-Pounds
| |
|---|---|---|
|
5/8
|
45 to 60
| |
|
3/4
|
75 to 90
| |
|
1
|
100 to 120
|
(c)
Coupled joints: assemble in accordance with the manufacturer's
recommendations.
(9)
Disassemble and remake improperly assembled joints using a new gasket.
(10)
Cheek each pipe installed as to line and grade in place. Correct
deviation from line and grade immediately. A deviation from the designed
grade as shown on the drawings, or deflection of pipe joints, will
be cause for rejection.
(11)
Place sufficient compacted backfill on each section of pipe,
as it is laid, to hold firmly in place.
(12)
Clean interior of the pipe as work progresses. Where cleaning
after laying is difficult because of small pipe size, use a suitable
swab or drag in the pipe and pull forward past each joint immediately
after the jointing has been completed.
(13)
Keep trenches and excavations free of water during construction.
(14)
When the work is not in progress, and at the end of each work
day, securely plug open ends of pipe and fittings to prevent trench
water, earth, or other substances from entering the pipes or fittings.
(15)
Deflection. When it is necessary to deflect pressure sewer mains
from a straight alignment horizontally or vertically, do not exceed
the following limits:
(16)
Make connections in accordance with the drawings, and perform
any adjustments and ensure a watertight installation. Connections
to the existing sewers shall be made under the direct observation
of the municipality or his authorized representative. Do not permit
any water, earth, debris or other materials to enter the existing
sewer system.
(17)
As soon as connections are completed, install an adequately
sized plumber's stopper in the existing manhole and brace to
prevent a blowout. The stopper is to prevent flow from the new line
from entering the existing system and it shall not be removed until
written authorization to do so is given by the municipality. Routinely
remove any accumulated ground and surface water from the line upstream
and shall be totally responsible for any damages to existing facilities.
C.
Wye branches and tees.
(1)
Install wye branches or pipe tees at locations designated concurrent
with pipe-laying operations. Use standard fittings of the same material
and joint type as the pipeline into which they are installed.
(2)
For taps into an existing pipeline, install a wye or tee with stainless
steel clamps and watertight resilient boot.
(3)
Where specifically approved by the municipality, for taps into an
existing pipeline, use a saddle wye or tee with stainless steel clamps
or core drill pipe and install watertight resilient boot. Mount saddles
with gasket and secure with metal bands. Lay out holes with a template
and cut holes with a mechanical hole cutter.
(4)
Where lateral is not to be installed, install an approved watertight
plug, braced to withstand pipeline test pressure thrust.
D.
Laterals.
(1)
Construct laterals from the wye branch to a terminal point in accordance
with Standard Detail DT 02610-1.[1] Lateral risers are not permitted.
[1]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
(2)
Install an approved watertight plug, braced to withstand pipeline
test pressure thrust, at the termination of the lateral. Install a
temporary marker stake (minimum two inches by two inches) extending
from the end of the lateral to one foot above finished grade.
(3)
Laterals shall be installed at a slope of one-quarter-inch/foot (four-inch
diameter) or one-eighth-inch/foot (six-inch diameter) from the main
to the cleanout or plug. The minimum depth under streets shall be
five feet. Any deviations must be approved by the municipality prior
to installation.
F.
Cradles and encasement: Provide concrete cradles and encasement for
pipeline where indicated on the drawings, or as directed by the municipality,
and in accordance with Standard Detail DT 03050-1.[2]
[2]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
G.
Thrust restraint for pressure pipelines.
(1)
Provide all valves, tees, bends, caps, and plugs with concrete thrust
blocks in accordance with Standard Detail DT 03050-3.[3] Pour concrete thrust blocks against undisturbed earth.
Locate thrust blocks to contain the resultant force and so pipe and
fitting joints will be accessible for repair.
[3]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
(2)
Furnish and install, tie rods, clamps, set screw retainer glands,
or restrained joints if indicated on the drawings or required by the
municipality. Protect metal restrained joint components against corrosion
by applying a bituminous coating.
I.
Stream crossings.
(1)
Construct sanitary sewer pipeline stream crossings in accordance
with Standard Detail No. DT 02221-2.[4]
[4]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
(2)
Provide concrete-encased ductile iron pipe backfilled with minimum
three-inch size stone to the level of the stream bed, between the
limits of the stream crossing.
J.
Backfilling trenches.
(1)
Backfill pipeline trenches only after examination of pipe by the
municipality.
(3)
Install the detectable warning tape along the entire length of PVC
force main on top of the pipe bedding but no deeper than 48 inches
below finished grade. The pipe bedding (twelve-inch cover) shall maintain
sufficient separation between the tape and the line.
L.
Bypass pumping.
(1)
Provide one reliable pump capable of handling the existing wastewater
flows and daily fluctuations and enough discharge piping to bypass
pump from upstream manhole to downstream manhole. Provide one backup
pump on-site or provide evidence of ability to obtain backup pump
within 30 minutes in case of pump failure. Bypass pumping system shall
not allow backup in collection system beyond two manholes. Bypass
piping shall be watertight and not allow any discharge to the surface.
Any leaks in the system will be just cause to discontinue bypass operation
and pipe installation and tie piping back into gravity flow.
(2)
At the end of each workday, the bypass pumping shall stop and the
new PVC piping shall be connected to the existing piping with a watertight
flexible coupling. All trenches shall be properly backfilled and compacted
except in the immediate area of the tie-in. Open trenches in traffic
areas shall be protected with jersey barriers and steel plating and
all trenches shall be protected with construction fencing.
