[R.O. 2012 §410.140; Ord. No. 2438 §3, 6-8-1998; Ord.
No. 2936 §1(B), 11-8-2004; Ord. No. 3428 §1, 12-8-2008]
A. Materials Of Construction. Piping, valves and fittings shall
be furnished and installed in accordance with the manufacturer's requirements.
All pipe and materials shall be new and in a condition satisfactory
to the City of Union. Materials of construction for water supply pipes
and fittings shall be as follows:
1. Water main.
b. C900 PVC water mains. All water mains shall be designed
with a pressure rating of one and one half (1.5) times the operating
pressure. Water mains may be AWWA conforming C900 DR 14 Class 200.
Pipe must bear the seal and approval of the National Sanitation Foundation.
Net laying lengths must be twenty (20) feet. Joints shall be integral
bell position joints with single rubber gasket making a pressure tight
seal.
c. Ductile iron pipe. Ductile iron pipe for use on
water mains under these specifications shall be cement lined super
belt-tite push-on joint; manufactured of materials and methods meeting
the test set forth in the latest revision of ANSI A21.51 (AWWA C151)
for Class 50 ductile iron pipe. Pipe shall have a working pressure
of three hundred fifty (350) psi.
d. Fittings for PVC mains. For PVC pipe flanged and/or
mechanical joints cast-iron fittings for PVC pipe shall be used and
shall meet the requirements of ANSI A21.11 (AWWA C111). Fittings shall
include appropriate transition gaskets.
e. Valves for PVC. Valves for water lines shall be
Mueller Model A-2360-20 mechanical joint, non-rising stem, resilient
wedge gate valves or approved equal. Each valve shall include the
required Mueller mechanical joint accessories. Said valves shall be
of the size required in the approved plans. All valves shall be manufactured
in accordance with AWWA Standard C509.
f. Valve for ductile iron pipe. Valves for water lines
shall be Mueller Model A-2360-20 mechanical joint, non-rising stem,
resilient wedge gate valve or approved equal. Each valve shall include
the required Mueller mechanical joint accessories. Said valves shall
be of the size required in the approved plans. All valves shall be
manufactured in accordance with AWWA Standard C509.
g. Valve boxes. Valve boxes shall be Mueller Model
H-10360 buffalo-type with lid as manufactured by the Mueller Company
or approved equal.
h. Fire hydrants. Fire hydrants shall comply with American
Water Works Association specifications. Hydrants shall have: two (2)
piece standpipe; compression type main valve; five and one-fourth
(5¼) inch valve opening; two (2) two and one-half (2½)
inch hose nozzles; one (1) four and one-half (4½) inch pumper
nozzle; mechanical joint inlet with cast-iron retainer glands; seven-eighths
(⅞) inch pentagon operating nut to open counter-clockwise.
Cast-iron fitting shall be cement mortar lines with bituminous seal
coat inside and out. Inlet connection shall be ten (10) inch mechanical
joint. Fire hydrants shall be Model 423 as manufactured by the Mueller
Company or approved equal. Said hydrants shall be equipped with auxiliary
gate valve and valve box and Mueller transition gland (A-399).
i. Tapping sleeve. Tapping sleeves for water lines
shall be Mueller Mechanical Joint Model H-304, stainless steel, and
flanged outlet as manufactured by the Mueller Company or approved
equal.
j. Tapping valve. Tapping valves for water lines shall
be Mueller flanged to mechanical Model T-2360-16, non-rising stem,
resilient wedge seat tapping valves or approved equal. Each valve
shall include the required Mueller transition glands (A-399). Said
valves shall be of the size required in the approved plans. All valves
shall be manufactured in accordance with AWWA Standard C509.
k. Detectable locator tape. Detectable location tape
shall be three (3) inches wide, bonded layer plastic with magnetic
foil core, Terra Tape Detectable, as manufactured by Griffolyn Company
of Houston, Texas, and shall have the words "Caution: Water Main Buried
Below", or approved equal.
l. Water line locator wire. Water line locator wire
shall be no. 12 copper wire, solid or strand, insulated for six hundred
(600) V with splice points near valve boxes.
2. Water service.
a. Service saddles. Service saddles for water lines
two (2) inches to twelve (12) inches shall be Mueller Bronze H-13000
series or approved equal, with tapped outlet as manufactured by the
Mueller Company or approved equal.
b. Corporation stops. Corporation stops for service
connections three-fourths (¾) inch to two (2) inches shall
be Mueller B-25008 or approved equal, "CC" thread with compression
connections. Larger sizes to be approved by the City of Union.
c. Curb values. Curb valves for service connections
three-fourths (¾) inch to two (2) inches shall be Mueller H-15209
or an approved equal, compression connections both ends. Larger sizes
to be approved by the City of Union. All curb valves to be Minneapolis
pattern.
d. Curb box. Curb box for service connections three-fourths
(¾) inch to one (1) inch shall be Mueller H-10316; one and
one-half (1½) inches to two (2) inches shall be Mueller H-10336
or approved equal, thirty-six (36) inches to forty (40) inches bury.
e. Service piping. Three-fourths (¾) inch to
two (2) inch service piping shall be Type K copper tubing or HDPE
CTS class 200 PE 3608 or PE 3710 SDR 9 ASTM D2737 or approved. PVC
SDR 21 class 200 is acceptable for two (2) water services. All service
piping shall have thirty-six (36) inches of minimum cover.
(1)
All non-metallic service piping must have #12 copper stranded
or solid tracing wire continuous with service piping, brought to surface
at curb valve.
(2)
All service piping under roadways must be in schedule 40 pvc
conduit, extended a minimum of twelve (12) inches past the curb line.
There shall be no service pipe joints under roadway.
(3)
All residential water service piping three-fourths (¾)
inch to two (2) inches located from the building interior to fifteen
(15) feet outside of building interior must be type K copper tubing.
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Service lines must be inspected by the City of Union prior to
backfilling.
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f. Meters. Service meters shall be a Schlumberger T-10 five-eighths
(⅝) inch to two (2) inches available from the City of Union.
All meters must be proceeded immediately by a ball valve. Meter shall
also be equipped with an ASSE approved dual check valve. Meters are
to be installed horizontal and sizes larger than two (2) inches to
be approved by the City of Union.
When necessary to install meter in an outside pit, plans and
specifications shall be submitted to the City of Union for approval.
3. All pipe and materials described above shall be of new materials
in a condition satisfactory to the City of Union.
4. All pipe and fittings shall be unloaded, hauled, and handled with
care to prevent injury to the pipe. Proper methods and equipment shall
be used for safe handling. Should a defect, gouge or crack be discovered
in any pipe, the crack or defective portion shall be cut off before
being installed so that the pipe will be perfectly sound. The cut
shall be made in the sound barrel at a point at least twelve (12)
inches beyond the visible limit of the defect.
5. The interior of the pipe shall be thoroughly cleaned of all foreign
matter and shall be kept clean during operations by means of plugs
or other approved methods. At all times when work is not in progress,
all open ends of pipes and fittings shall be securely closed. Tees
and fittings at bends in pipe shall be promptly braced with substantial
concrete thrust blocks.
B. Excavation Of Trenches.
1. General.
a. The contractor shall control the grading in the vicinity of pipe
trenches so that the surface of the ground will be properly sloped
to prevent water from running into the excavated areas. Any water
or other liquid wastes which accumulate in the excavations shall be
removed promptly.
b. The contractor shall perform all excavation work necessary for and
incidental to the proper construction of the water lines as shown
on the approved plans or directed by the City of Union. Excavation
shall include the removal of trees, shrubs and undesirable material.
Excavation shall be done along the lines indicated on the approved
plans and shall be continuous and straight without improper bends
and kinks. Trenches shall be only of sufficient width to provide a
free working space on each side of the pipe. During excavation, material
suitable for backfilling shall be stockpiled in an orderly manner
a sufficient distance from the banks of the trenches to avoid overloading
which might cause slides or cave-ins. All excavated materials not
suitable for backfill shall be removed by the contractor and disposed
of in a manner approved by the City of Union. The contractor shall
provide all barricades, lights, temporary crossings, warning signs,
etc., that may be necessary to properly protect the public and the
work from injury or damage.
2. Depth. Trenches for water pipe shall be opened to
a sufficient depth to obtain a minimum of forty-two (42) inches of
cover over the top of the pipe. All excavations shall be made so as
to provide a continuous bearing for the barrel of the pipe. Bell holes
shall be excavated to sufficient size to permit ample room for making
joints. The bottom of trenches shall be free from rocks, clods, debris
and other unsuitable material and shall consist of properly shaped
earth or tamped granular material as specified herein. The contractor
shall be careful not to excavate below grade except to remove undesirable
material, or as directed by the City of Union.
3. Width. No excavated trench shall be wider than one
and four-tenths (1 4/10) times the pipe diameter in inches plus twelve
(12) inches (width = 1.4d" + 12") or two (2) feet wide or as designated
by the City of Union.
4. Trench excavation classifications. All excavation
shall consist of two (2) classifications, vis: Class "A" and Class
"B".
a. Class "A" excavation. Class "A" excavation shall
consist of all other materials not mentioned in Class "B". The decision
of the City of Union shall be final on the determination of the proper
classification.
b. Class "B" excavation. Any material shall be considered
Class "B" excavation which in the opinion of the City of Union, cannot
be excavated by any process other than drilling and blasting or drilling
and wedging. This classification shall not be extended to include
the materials which can be removed by other means, but which for reasons
of economy in excavation, it is preferred to remove by drilling and
blasting or drilling and wedging. Such excavation shall include detached
pieces of rock or boulders one (1) cubic yard or more in content and
masses of solid, well-defined ledges of stone or masses of rock, slate,
shale or soapstone and other similar substances. Class "B" excavation
shall be stripped for measurement in sections of such length as the
City of Union may direct, and no rock excavated or blasted before
such measurements will be allowed. "Stripping" shall
mean the removal of all other materials so as to expose the surface
of the rock.
(1)
Explosives. Explosives shall only be used of
such character and strength and in such manner as may be permitted
by the City of Union. All necessary precautions shall be taken to
prevent accidents and injury or damage to adjacent buildings. Blasts
shall be completely and carefully covered with heavy timbers or other
adequate protection and shall be made only between such hours as may
be designated by the City of Union. The contractor shall be liable
for all injuries or deaths of persons or damages to property caused
by blasting or explosives.
(2)
Measurement. All Class "B" excavation shall
be measured in place by the cubic yard. No loose, shaken or previously
blasted rock will be allowed as Class "B" excavation, nor shall any
excavation exterior to the maximum limits of measurement be allowed.
C. Pipe Laying.
1. General. Laying of the pipe shall be commenced immediately
after the excavation is started, and the contractor must use every
means at his/her command to keep pipe laying closely behind the trenching.
The City of Union may stop the trenching when, in his/her opinion,
the trench is open too far in advance of the pipe laying operation.
The contractor may lay pipe in the best manner adapted to securing
speed and good results. It shall, however, be in accordance with the
manufacturer's instructions and recommendations, and in a manner that
will not damage the pipe.
2. Thrust blocking. Lines shall be thrust blocked at
bends, tees and hydrants to prevent movement of lines under pressure.
The concrete blocking shall be placed between solid ground and the
filling to be anchored in such a manner that the pipe and fitting
joints will be accessible for repairs. Thrust blocks shall be constructed
in accordance with the following table.
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SQUARE FEET OF THRUST BLOCK AREA RECEIVED
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Pipe Size
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Dead End Tee Or In-Line Valve
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90° Elbow
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45° Elbow
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22½° Elbow
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2 inches
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Minimum
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Minimum
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Minimum
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Minimum
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4 inches
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Minimum
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Minimum
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Minimum
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Minimum
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6 inches
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Minimum
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Minimum
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Minimum
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Minimum
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8 inches
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2' x 2' 3"
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2' 8" x 2' 8"
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Minimum
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Minimum
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10 inches
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2' 10" x 2' 10"
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3' 6" x 3' 6"
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2' 6" x 2' 6"
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Minimum
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Minimum thrust block bearing to be two (2) square feet.
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3. Laying. Damaged or unsound pipe or fittings will
be rejected. Pipe shall be laid with bells facing the direction of
laying. Joints shall be made as specified above. Before joining the
pipe, all lumps, blisters, excess coating material, and any grease
or oil shall be removed from gaskets and the bell and spigot ends
of the pipes.
4. Pipe bedding. Pipe shall be laid in a flat bottom
trench with backfill material approved by the City of Union deposited
into the trench uniformly at both sides of the pipeline for the full
width of the trench, up to the horizontal diameter of the pipeline.
D. Backfilling For Trenches.
1. General. When the pipe is laid, the contractor shall
backfill under and around the pipe until the pipe is covered with
sufficient material to hold the pipe in position when firmly tamped.
The remainder of the trench shall then be carefully backfilled simultaneously
on both sides of the pipe. Broken concrete or pavement, blasted rock
and large boulders shall not be used as backfill materials. Any trenches
improperly backfilled, or where settlement occurs, shall be repaired
as directed by the City of Union. The ground shall be graded to a
reasonable uniformity and the required amount of mounding over the
trenches left in a uniform and neat condition. Before final acceptance
is made, the contractor shall travel the line with the City of Union
and any settled places shall be repaired as directed by the City of
Union. It is the intent of these specifications to secure a condition
where no further settlement of trenches will occur after backfilling
is completed.
2. Backfilling for trenches in unpaved areas. The entire
backfill for trenches in areas other than areas to be paved as indicated
in the approved plans shall be repaired as directed by the City of
Union. It is the intent of these specifications to secure a condition
where no further settlement of trenches will occur after backfilling
is completed.
3. Backfill in paved areas. In areas of existing or
proposed pavement or rock surfaces, the entire backfill shall consist
of well graded one (1) inch minus crushed limestone. The backfill
material shall be compacted by an acceptable method to insure that
no settlement of the completed backfill will occur. All areas of existing
pavement damaged during construction shall be repaved with two (2)
inches of Type C asphaltic pavement and installed in accordance with
the latest edition of the Missouri Standard Specifications for Highway
Construction. Edges of the existing pavement shall be neatly cut in
a straight line, removing all damaged pavement, prior to repaving.
4. Responsibility of contractor for backfill settlement. The contractor shall be responsible for the satisfactory compaction
of backfill material described. If any trenches or other excavation
are found to have settled, they shall be immediately reworked by the
contractor and restored to the specified grades. In addition, the
contractor shall be responsible for all damage or damages which might
result from settlement of backfill made by him/her of the fulfillment
of his/her contract within and during the period of one (1) year from
and after the date of final acceptance thereof by the City of Union.
5. Finish grading. The finishing of side slopes, cuts
and fills shall be reasonably smooth uniform surfaces that will merge
with the adjacent terrain without noticeable break.
6. Protection of existing sewers, structures or utilities. Where new lines approach, cross, connect to, or run parallel to
existing sewer, structures, or other utilities, the contractor shall
be held completely responsible for protecting, preserving, and otherwise
maintaining existing improvements during construction of the new lines.
Any damage inflicted must be promptly repaired to the satisfaction
of the City of Union. Costs involved for any and all repairs shall
be at the contractor's expense.
7. Testing water lines.
a. All newly laid lines shall be tested before being placed in service.
Trenches may be backfilled as the pipe is laid; or where practicable,
trenches or bell holes may be left open for visual inspection during
tests. Prior to making tests, all air shall be expelled from the pipes.
If hydrants or blow-offs are not available at high points of the lines,
suitable taps shall be provided at such points.
b. A one (1) hour hydrostatic test shall be made on the pipeline between
valves or temporary plugs at a test pressure of at least fifty percent
(50%) in excess of normal operating pressure. Any open trench or bell
holes made over dry joints may be backfilled following this test.
Where trenches have been backfilled prior to making the test, any
leaks evident at the surface shall be remade and retested. All pipes,
fittings, valves, hydrants and other materials found defective under
this test shall be removed and replaced.
c. After hydrostatic tests have been satisfactorily completed, a two
(2) hour leakage test shall be made on the pipeline valves or temporary
plugs at a constant test pressure of seventy-five (75) pounds per
square inch. Leakage in the test system shall be measured through
a meter or approved measuring device. The allowable leakage shall
not be greater than seventy (70) gallons per twenty-four (24) hour
day per mile of pipe per inch nominal diameter of pipe. Should tests
disclose leakage greater than the allowable amount, locate and repair
defective joint(s) until the leakage is within the specified allowance.
E. Water Mains Near Sewers.
1. Horizontal separation. Whenever possible, a water
main shall be laid at least ten (10) feet horizontally from any sanitary
sewer, storm sewer or manhole. When local conditions prevent a lateral
separation of ten (10) feet, a water main may be laid closer than
ten (10) feet of (or in the same trench as) a sanitary or storm sewer,
provided that the water main is laid in a separate trench, or on an
undisturbed earth shelf located on one (1) side of the sewer at such
an elevation that the bottom of the water main is at least eighteen
(18) inches above the top of the sewer. When it is impossible to obtain
properly horizontal and vertical separation as stipulated above, both
the water main and sewer must be constructed of mechanical, slip-on,
or lead joint cast-iron pipe, or pre-stressed concrete cylinder pipe,
and should be pressure-tested to assure water-tightness before backfilling.
2. Vertical separation. Whenever a water main must
cross sanitary sewers, house sewers or storm drains, the water main
shall be laid at such an elevation that the bottom of the water main
is eighteen (18) inches above the top of the drain or sewer. A full
length of water main pipe shall be centered over the sewer line to
be crossed so that the joints will be equally distant from the sewer
line to be crossed so that the joints will be equally distant from
the sewer and as remote therefrom as possible. This vertical separation
shall be maintained for that portion of the water main located within
ten (10) feet horizontally of any sewer or drain it crosses.
3. Unusual conditions. Where conditions prevent the
minimum vertical separation set forth above from being maintained,
or when it is necessary for the water main to pass under a sewer or
drain, the water main shall be laid with mechanical joint cast-iron
pipe and the cast-iron pipe shall extend off each side of the crossing
to a distance from the sewer of at least ten (10) feet. In making
such a crossing, a full length of water main pipe must be centered
over or under the sewer to be crossed, so that the joints will be
equi-distant from the sewer and as remote therefrom as possible. The
sewer line must also be constructed of cast-iron pipe with slip-on,
leaded, or mechanical joints until the normal distance from the sewer
line to the water main is at least ten (10) feet. Where a water main
must cross under a sewer, a vertical separation of eighteen (18) inches
between the bottom of the sewer and the top of the water main shall
be maintained, with adequate support, especially for the larger sized
sewer line to prevent them from settling on and breaking the water
main. The sewer shall be constructed of cast-iron pipe for a distance
of ten (10) feet on either side of the crossing, or other suitable
protection as approved by the Division of Health shall be provided.
Where these conditions cannot be met, the Division of Health shall
be consulted as to the precautions to be taken to protect the public
water supply.
4. Sewer manholes. No water pipes shall pass through,
or come into contact with, any part of the sewer or sewer manhole.
F. Disinfecting Water Lines.
1. General.
a. The interior of all pipe, fittings, and other accessories shall be
kept free as possible from dirt and foreign matter at all times.
b. Every precaution shall be used to protect the pipe against the entrance
of foreign material before the pipe is placed in the new line. At
the close of the day's work or whenever the workmen are absent from
the job, the end of the last laid section of pipe shall be plugged,
capped or otherwise tightly closed to prevent the entry of foreign
material of any nature. If the pipe laying crew cannot put the pipe
into the trench and in place without getting earth into it, the City
of Union may require that before lowering the pipe into the trench,
a heavy, tightly woven canvas bag of suitable size shall be placed
over each end, and left there until the connection is to be made to
the adjacent pipe.
c. At times when pipe laying is not in progress, the open ends of pipe
shall be closed by a water-tight plug or other means approved by the
City of Union. Joints of pipe in the trench shall be made before the
work is stopped. This provision shall apply during the noon hour as
well as overnight.
2. Flushing and sterilizing completed pipelines.
a. Sterilizing of the completed line shall be done in a manner approved
and recommended by the Missouri Division of Health.
b. Prior to chlorination, the main shall be flushed as thoroughly as
possible with the water pressure and outlets available. Flushing shall
be done after the pressure tests are made. It must be understood that
such flushing removes only the lighter solids and cannot be relied
upon to remove heavy material allowed to get into the main during
laying.
c. Unless extreme care and thorough inspection is practiced during the
laying of water mains, small stones, pieces of concrete, particles
of metal, or other foreign material may gain access to mains newly
laid. If it is believed that such foreign material may be in the main,
it shall be thoroughly flushed and valves carefully inspected after
flushing to see that the entire valve operating mechanism is in good
condition.
d. Subsequent to flushing, the following procedure shall be followed
in disinfecting the water mains.
(1)
Close off section of distribution system that is to be disinfected.
(2)
Prepare one percent (1%) chlorine solution as shown in the following
Table:
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Product
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Amount of Compound
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Quantity of Water to Add to Make 1% Solution
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High test calcium
Hypo-Chlorite (65 — 70% Chlorine, HTH
Parachloron, etc.)
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1 lb.
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7.5 gal.
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Chlorinated Lime
(32 — 35% Chlorine)
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2 lbs.
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7.5 gal.
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Liquid laundry
bleach (Purex or Clorox)
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1 gal.
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4.25 gal.
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(3)
The amount of chlorine required per one hundred (100) foot length
of various pipe sizes is as shown in the following Table:
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Pipe Size
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Volume of 100 ft. Length
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Amount Required to Give 25 ppm Chlorine
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(in)
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(gal)
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100% Chlorine (lb)
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1% Chlorine/
Water (gal)
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2
|
16.4
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0.0034
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1/24
|
|
4
|
65.3
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0.0135
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1/6
|
|
6
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146.5
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0.0305
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⅜
|
|
8
|
261.0
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0.054
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2/3
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10
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408.0
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0.085
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1
|
|
12
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588.7
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0.123
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1½
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(4)
Introduce the chlorine solution with a positive displacement
type pump at the same point where the water will be introduced into
the section to be disinfected.
(5)
Fill the pipe slowly and be sure not to trap any air in the
pipe. Close the section off that is to be disinfected when the pipe
is full and under slight pressure. The solution should be allowed
to remain in the pipe for twenty-four (24) hours.
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Note:
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The detention time may be cut to three (3) hours, provided a
one hundred (100) ppm chlorine solution is used in place of the twenty-five
(25) ppm chlorine solution.
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(6)
All valves or other appurtenances in the line being disinfected
should be operated while the system is being filled with the chlorine
solution.
e. Following sterilizing, all treated water shall be thoroughly flushed
from the newly laid pipeline at its extremities until the replacement
water throughout its length shall, upon test, be proved comparable
to the quality of water approved by the public health authority having
jurisdiction. The contractor or his/her representative shall arrange
for any bacteriological testing of water samples that may be required.
This quality of water delivered by the new main should continue for
a period of at least two (2) full days, as demonstrated by laboratory
examination of samples taken from a tap located and installed in such
a way as to prevent outside contamination. Samples should never be
taken from an unsterilized hose or from a hydrant, because such samples
seldom meet current bacteriological standards.
f. Should the initial treatment fail to result in the condition specified
in the preceding paragraph, the sterilizing procedure shall be repeated
until such results are obtained.
G. Cleaning Of The Grounds. During the progress of the work,
the contractor shall remove and properly dispose of all debris and
waste material. Upon completion and acceptance of the work, remove
from the property of the City of Union all equipment and facilities
and unused material provided by him/her in connection with the work
and leave the grounds in a clean and orderly condition.
H. Restoration Of Disturbed Area. Any and all areas that are
disturbed as a result of construction shall be restored to an "as
good or better" condition as existed prior to being disturbed.
[R.O. 2012 §410.150; Ord. No. 2438 §3, 6-8-1998]
A. Materials — PVC Solid Wall Sewer Pipe. Pipe and fittings
under these specifications shall be PVC solid wall pipe with bell
and spigot gasketed joints, manufactured of materials and methods
meeting the tests set forth in the latest revision of ASTM D-3034
and ASTM D-3212. PVC sewer pipe shall have a maximum standard dimension
ratio of thirty-five (35).
B. Underground Pipe Construction.
1. Underground pipe construction shall be in accordance with the recommended
practice as outlined by the pipe manufacturer.
2. All excavations shall be made to such depths and widths as will give
ample room for building all structures, sewers and appurtenances as
detailed on the approved plans.
3. Clearing and grubbing the site of work, excavation of earth or other
materials, sheeting and bracing, pumping and drainage, backfilling,
rough grading, and cleaning up shall all be done as specified. In
addition, all work maintaining or replacing existing fences, roadways,
drives, lawns or structures disturbed by the work, safety precautions
and other miscellaneous general work not specified under specific
items is to be included in the work done under this Section.
C. Sewer Pipes.
1. All sewer pipe shall be laid accurately to the line and grades indicated
on the approved plans. The trench excavation shall be of sufficient
width to properly construct the joints and to allow for inspection
of proper bedding of the pipe. In all cases, the bottom quadrant of
the pipe trench should be carefully shaped at proper intervals so
that no part of the load is supported by the pipe bells. The full
load should rest on the barrel of the pipe.
2. To assure stable pipe bedding, mechanical excavation should be made
four (4) inches below the bottom of the pipe grade. A layer of compacted
granular material at least four (4) inches thick shall be provided
to stabilize the trench bottom.
3. The grades to which all sewer lines are laid shall be accurately
controlled, providing grade stakes and batter board at twenty-five
(25) foot intervals and checking invert elevations with a grade rod
from an established grade line.
4. A laser beam may be used to attain proper alignment of sewer pipe
during construction. However, if such a device is used, a blower of
sufficient capacity to prevent defraction of the beam by fumes from
joint lubricant must be used.
5. No pipe shall be installed in the trench until the bottom of the
trench has been properly shaped and its conditions, line and grade
has been approved by the City of Union.
6. All sewers must be laid in a straight line so that a light can be
seen from one end to the other. Pipe shall be laid with the spigot
end downstream entering the bell to full depth, and in such manner
as not to drag earth into the joints. Pipe sections shall be fitted
together and matched so that, when laid, they will form a sewer with
a smooth and uniform invert. Installation shall be in accordance with
manufacturer's recommendations.
7. Wherever obstructions are encountered during the progress of the
work and interfere to such an extent that an alteration in the plan
is required, the City of Union shall have the authority to change
the approved plans and order a deviation from the line and grade or
arrange with the City of Union of the structures for the removal,
relocation or reconstruction of the obstructions.
D. Cutting And Trenching Excavation.
1. If local conditions permit their reuse, all surface materials suitable
for reuse in restoring the surface shall be kept separate from the
general excavation material.
2. All excavated material unsuitable for backfill shall be removed and
disposed of off the site, by and at the expense of the contractor.
3. All excavated material shall be piled in a manner that will not endanger
the work and that will avoid obstructing walks and driveways. Ditches
shall be kept clear or other satisfactory provisions made for drainage.
4. All excavations shall be made to such depths and widths as detailed
on the approved plans, or as embodied in the specifications or as
will give ample room for carrying on the required construction operations.
5. No excavated trench shall be wider than one and four-tenths (1 4/10)
times the pipe diameter in inches plus twelve (12) inches (width =
1.4d" + 12") or two (2) feet wide or as designated by the City of
Union.
6. Granular backfill material shall be tamped into the trench uniformly
on both sides of the pipeline for the full width of the trench, up
to the horizontal diameter of the pipeline.
7. No large rocks shall be allowed in contact with the pipe either in
the bed or the backfill. Large rocks occurring in the bed shall be
removed and the resulting hole filled with gravel.
8. Bell holes shall be of ample depth to permit the barrel of the pipe
totally flat on the trench bottoms, but they shall not be larger than
necessary or properly making the joint.
E. Trench Excavation Classifications. All excavation shall
consist of two (2) classifications, vis: Class "A" and Class "B".
1. Class "A" excavation. Class "A" excavation shall
consist of all other materials not to be mentioned in Class "B". The
decisions of the consultants shall be final in the determination of
the proper classification.
2. "Class "B" excavation. Any materials shall be considered
Class "B" excavation which, in the opinion of the consultant, cannot
be excavated by any process other than drilling and blasting or drilling
and wedging. The classification shall not be extended to include the
materials which can be removed by other means, but which, for reasons
of economy in excavation, it is preferred to remove by drilling and
blasting or drilling and wedging. Such excavation shall include detached
pieces of rock or boulders one (1) cubic yard or more in contents
and masses of solid, well-defined ledge of stone or masses of rock,
slate, shale, or soapstone and other similar substances. Class "B"
excavation shall be stripped for measurement in sections of such length
as the consultant may direct, and no rock excavated or blasted before
such measurements will be allowed. "Stripping" shall
mean the removal of all other materials so as to expose the surface
of the rock.
a. Explosives. Explosives shall only be used of such
character and strength and in such manner as may be permitted by the
City of Union. All necessary precautions shall be taken to prevent
accidents and injury or damage to adjacent buildings. Blasts shall
be completely and carefully covered with heavy timbers or other adequate
protection and shall be made only between such hours as may be designated
by the City of Union. The contractor shall be liable for all injuries
or deaths of persons or damages to property caused by blasting or
explosives.
b. Measurement. All Class "B" excavations shall be
measured in place by the cubic yard. No loose, shaken or previously
blasted rock will be allowed as Class "B" excavation, nor shall any
excavation exterior to the maximum of measurements be allowed.
F. Sheeting And Bracing.
1. Furnish, put in place, and maintain such sheeting, braces, rangers,
and other timbering as may be required to support the sides of the
excavation and to prevent any movement which could in any way injure
the sewers, diminish the necessary width of the excavation or otherwise
injure or delay the work or endanger adjacent pavements, buildings,
sewers, pipes, drains, conduits or other structures, or the lives
or workmen employed thereon.
2. The City of Union may direct that sheeting in the trench be cut off
at any specified elevation and in no case without permission shall
timber be left in the ground above an elevation eighteen (18) inches
below the surface of the ground.
3. All timber which may not be left in place under the foregoing provisions
of this specification shall be removed in such manner as not to endanger
adjacent pavements, structures or property, or to cause movement of
the pipe or endanger the structure built in the excavation from which
the timber of sheeting is being removed or adjacent thereto. All voids
left by withdrawal of sheeting shall be immediately refilled with
sand or fine earth by ramming with tools especially adapted to that
purpose, by watering, or otherwise as may be directed by the City
of Union.
G. Laying Pipe.
1. The pipe lines shall be constructed of such sizes and laid accurately
to such lines and grade as are shown in the approved plans. Pipe material
shall meet the requirements of the material specifications. Branches,
fittings, and specials shall be provided, and when not to be immediately
used shall be closed with earthenware or pre-cast concrete stoppers
sealed in place with bituminous mastic. When immediate use is to be
made of them, they may be closed with a plywood stopper. The sewer
at the end of the day's laying shall be closed with dirt-tight temporary
stopper.
2. The interior of the sewers shall, as the work progresses, be cleared
of all dirt, cement and superfluous materials of every description.
On all diameter sewer, an approved swab or drag shall be kept in the
pipeline and pulled forward past each joint immediately after its
completion.
3. Variance from established line and grade shall not exceed one-half
(½) inch, provided that any such variation does not result
in a level or reverse sloping invert; provided also, that variation
in the invert elevation between adjoining ends of pipe due to non-concentricity
of joining surface and pipe interior surfaces does not exceed one-fourth
(¼) inch maximum.
4. Unless otherwise permitted, as least four (4) finished joints shall
be left exposed for inspection throughout the working day, and any
and all sections of pipe laid shall be made accessible for inspection
at any time while the work is progressing.
5. Pipe shall not be laid in water. No walking on or walking over the
pipe will be permitted after they are laid except as may be necessary
for backfilling and tamping.
6. Pipe shall be laid true to line and grade shown in the approved plans
and shall be firmly supported for its entire length when laid in trench.
H. Backfilling For Trenches.
1. General. When the pipe is laid, the contractor shall backfill under and around the pipe as specified in Section
410.160(D)(1). The remainder of the trench shall then be carefully backfilled simultaneously on both sides of the pipe. Broken concrete or pavement, blasted rock and large boulders shall not be used as backfill materials. Any trenches improperly backfilled, or where settlement occurs, shall be repaired as directed by the City of Union.
2. Backfill in paved areas. In areas of existing or
proposed pavement or rock surfaces, the entire backfill shall consist
of well-graded one (1) inch minus crushed limestone. The backfill
material shall be compacted to ninety percent (90%) of the modified
proctor density by an acceptable method to ensure that no pavement
settlement of the completed backfill will occur. All areas of existing
pavement damaged during construction shall be repaved with three (3)
inches of Type C asphaltic pavement and installed in accordance with
the latest edition of the Missouri Standard Specifications for Highway
Construction. Edges of the existing pavement shall be neatly cut in
a straight line, removing all damaged pavement prior to repaving.
3. Backfill in areas that are not paved. The entire
backfill for trenches in these areas shall be compacted to eighty-five
percent (85%) of the modified proctor density as directed by the City
of Union. It is the intent of these specifications to secure a condition
where no further settlement of trenches will occur after backfilling
is completed.
4. Compaction. Care shall be exercised not to disturb
pipe when placing backfill. All backfill or trenches shall be placed
in uncompacted lifts not to exceed eight (8) inches in thickness,
and each lift shall be compacted in a manner approved by the City
of Union.
5. Responsibility of contractor for backfill settlement. The contractor shall be responsible for the satisfactory compaction
of backfill material described. If any trenches or other excavation
are found to have settled, they shall be immediately reworked by the
contractor and restored to the specified grades. In addition, the
contractor shall be responsible for all damage or damages which might
result from settlement or backfill made by him/her on the fulfillment
of his/her contract within and during the period of one (1) year from
and after the date of final acceptance thereof by the City of Union.
6. Finish grading. The finishing of side slopes, cuts
and fills shall be reasonably smooth uniform surfaces that will merge
with the adjacent terrain without noticeable break. Finishing shall
be done in accordance with grades shown on the approved plans and
without variations that are readily discernible.
I. Testing Of Sewers.
1. General. After construction and backfilling are
completed and before any services are connected to the sewers, the
completed lines shall be tested for leaks and visually checked for
straightness of line and cracked pipe. If any deficiencies in line
or grade are found which will be detrimental to the proper functioning
of the sewer, the deficiencies shall be corrected. Any damaged or
cracked pipe shall be excavated and relayed in a manner satisfactory
to the City of Union. Any section of sewer which is found to be leaking
in excess of the allowable quality shall be repaired.
2. Acceptance tests Each reach of sewer shall meet
the requirements of the following acceptance tests. All defects shall
be lamped. Lamping will be performed by the City of Union.
a. Lamping. Each section of sewer line between manholes
shall be straight and uniformly graded. Each such section shall be
repaired to the satisfaction of the City of Union.
b. Exfiltration. The total exfiltration shall not exceed
two hundred (200) gallons per inch of nominal diameter per mile of
pipe per day. For purposes of determining maximum allowable leakage,
manholes shall be considered section of forty-eight (48) inch pipe.
c. Infiltration. Pipe joints shall be protected from
damage in the field prior to laying. Lubricants, primers, adhesives,
etc., shall be recommended by the pipe manufacturer's specifications
to obtain the degree of water-tightness required. The maximum rate
of infiltration shall not exceed two hundred (200) gallons per inch
of pipe diameter per day per mile when tested in accordance with the
testing procedure set up in ASTM Designation C-425. If infiltration
exceeds this rate, the leakage source(s) shall be located and repairs
made as necessary.
J. Sewers Near Water Mains.
1. Horizontal separation. Whenever possible, sanitary
sewers and manholes shall be located at least ten (10) feet, horizontally,
from any water main. When local conditions prevent a lateral separation
of ten (10) feet, a sewer may be laid closer than ten (10) feet to
a water main, provided that the water main is at least eighteen (18)
inches above the top of the sewer. When it is impossible to obtain
proper horizontal and vertical separation as stipulated above, both
the water main and sewer must be constructed of mechanical slip-on
joint pipe and should be pressure-tested to assure water-tightness
before backfilling.
2. Vertical separation. Whenever sanitary sewers or
house sewers must cross water mains, the sewer shall be laid at such
an elevation that the bottom of the water main is eighteen (18) inches
above the top of the drain or sewer. A full length of water main pipe
shall be centered over the sewer line to be crossed as that the joints
will be equally distant from the sewer and as remote therefrom as
possible. This vertical separation shall be maintained for the portion
of the water main located within ten (10) feet, horizontally, of any
sewer or drain it crosses.
3. Unusual conditions. Where conditions prevent the
minimum vertical separation set forth above from being maintained,
or when it is necessary for the water main to pass under a sewer or
drain, the water main shall be laid with mechanical joint cast-iron
pipe, and the cast-iron pipe shall extend on each side of the crossing
to a distance from the sewer of at least ten (10) feet. In making
such a crossing, a full length of water main pipe must be centered
over or under the sewer and as remote therefrom as possible. The sewer
line must also be constructed of cast-iron pipe with slip-on joints
until the normal distance from the sewer line to the water main is
at least ten (10) feet.
[R.O. 2012 §410.160; Ord. No. 2438 §3, 6-8-1998]
A. Material Specifications, PVC Pressure Rated Pipe And Fittings.
1. PVC force main.
a. Pipe. Water mains shall be PVC Class 200. Pipe shall
conform to ASTM D2241 and shall be pressure rated at two hundred (200)
psi at seventy-three degrees Fahrenheit (73°F) with a standard
dimension ratio of SDR 21. PVC pipe must bear the seal of approval
of the National Sanitation Foundation. Net laying lengths must be
twenty (20) feet. Joints shall be integral bell push-on joints with
single rubber gasket making a pressure tight seal. Said pipe shall
be in accordance with ANSI/ASTM D2241-78 or the latest revision thereof.
b. Fittings for PVC pipe. Fittings for pipe sizes two
(2) inches through three (3) inches shall be made of the same quality
as pipe meeting the requirements of PS 22-70, ASTM D-2241 and ASTM
D-1784 and shall have elastomeric seal joints. For pipe sizes greater
than six (6) inches, flanged and/or mechanical joints cast-iron fittings
for PVC pipe shall be used and shall meet the requirements of ANSI
A21.11 (AWWA C111). Fittings shall include appropriate transition
gaskets.
c. For pipe sizes greater than four (4) inches, mechanical joint cast-iron
fittings for PVC pipe shall be used and shall meet the requirements
of ANSI Specification A21.11 (AWWAC111). Fittings shall include appropriate
transition gaskets.
2. Pipe and fitting compound. PVC compounds shall be
white in color for improved exposure resistance and shall comply with
ASTM D-1784, Rigid Poly (Vinyl Chloride) Compounds with physical properties
and chemical resistance of cell classifications for pipe of 12454-B,
12454-C or 14333-D and cell classifications for fittings of 12454-B,
12454-C or 13343-C. Different cell classifications having one (1)
or more superior properties and clean rework material generated by
the manufacturer's own production shall be acceptable.
3. Joints. Joints of both pipe and fittings shall comply
with ASTM D-3139, Joints for Plastic Pressure Pipes Using Flexible
Elastomeric Seals. Qualification test of the joint design shall result
in no leakage under various laboratory test conditions of joint alignment
at two (2) times rated pressure and at twenty-two (22) inch mercury
vacuum.
4. Gaskets. Gaskets shall be molded from a high grade,
properly vulcanized, elastomeric compound consisting of either a basic
natural or synthetic rubber. Gaskets shall be marked to show pipe
size and type.
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Note:
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Specifications for Elastomeric Seals for Thermoplastic Pipes
are being developed by ASTM. Until they are published, the compound
for elastomeric seal rubber gaskets shall generally comply with modified
physical requirements of ASTM Standard Specifications: D-1869, Rubber
Rings for Asbestos Cement Pipe; C361, Reinforced Concrete Low-Head
Pressure Pipe; and AWWA Standard C111 for Rubber Gasket Joints for
Cast-Iron Pressure Pipe and Fittings.
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5. Valves. Valves for force mains shall be Mueller
mechanical joint, non-rising stem, resilient wedge Model A-2360-20
seal, gate valves or approved equal. Each valve shall include the
required Mueller mechanical joint accessories. Said valves shall be
of the size required in the approved plans. All valves shall be manufactured
in accordance with AWWA Standard C-509.
6. Valve boxes. Valve boxes shall be Mueller Model
H-10360 buffalo-type with lid as manufactured by the Mueller Company
or approved equal.
7. Air release valves. Air release valves shall be
Valmatic Model 48 or approved equal with steel floats, resilient seating
and cast-iron housing.
8. Air/vacuum release valves. Air/vacuum release valves
shall be Valmatic Model 301 or approved equal with steel floats, Buna-N
seating and cast-iron housing.
B. Materials Of Construction.
1. Responsibility for materials.
a. Responsibility for material furnished by contractor. The contractor shall be responsible for all material furnished by
him/her and shall replace at his/her own expense all such material
found damaged or defective. This shall include the furnishing of all
material and labor required for the replacement of installed material
discovered defective prior to the final acceptance of the work.
b. Responsibility for safe storage. The contractor
shall be responsible for the safe storage of material furnished by
or to him/her and accepted by him/her and intended for the work until
it has been incorporated in the completed project. The interior, as
well as all sealing surfaces of all pipe, fittings and other accessories,
shall be kept free from dirt and foreign matter at all times. Fittings
shall be drained and stored in a manner that will protect them from
damage by freezing. Any material furnished by the City of Union that
becomes damaged after acceptance by the contractor shall be replaced
by the contractor at his/her own expense. Pipe stored outside for
a period longer than one (1) month shall be covered with canvass or
other opaque material. Clear plastic sheets shall not be used. Air
circulation shall be provided under covering.
2. Handling of pipe and accessories. Pipe and accessories
shall, unless contrary instructions are received, be unloaded at the
point of delivery and hauled to and distributed at the site of the
project by the contractor. They shall at all times be handled with
care to avoid damage.
C. Work To Be Performed.
1. Alignment and grade. All pipe shall be laid to and
maintained at the required lines and grades. Fittings shall be installed
at the required locations. No deviation shall be made from the required
line or grade without approval from the City of Union.
a. Deviations occasioned by other structures. Temporary
support, adequate protection and maintenance of all underground and
surface utility structures, drains, sewers, and other structures encountered
in the progress of the work shall be furnished by the contractor at
his/her own expense. Where the grade or alignment of the pipe is obstructed
by the existing utility structures such as conduits, ducts, pipes,
branch connections to main sewers or main drains, the obstruction
shall be permanently supported, relocated, removed or reconstructed
by the contractor in cooperation with the City of Union of such utility
structures. Whenever necessary to determine the location of existing
underground utility structures, the contractor, after an examination
of available records, shall make all explorations and excavations
for such purpose as may be directed by the City of Union. All pipe
shall be laid to depth shown on the approved plans or as directed
by the City of Union. The depth shall be measured from the established
street grade or the surface of the permanent improvement to the top
of the pipe barrel.
2. Excavation and preparation of trench.
a. General. The trench shall be dug to the required
alignment and depth shown on the approved plans or as subsequently
approved in writing by the City of Union, and only so far in advance
of pipe laying as permitted by the City of Union. Unless specified
otherwise, the minimum depth of pipe cover shall be forty-two (42)
inches.
b. Trench stability. Where necessary to prevent caving,
trench excavations in unstable soil shall be adequately supported.
Where sheeting and bracing are used the trench width shall not be
less than that specified hereafter. As backfill is placed and sheeting
is withdrawn, the void left by the withdrawn sheeting shall be filled
and compacted before withdrawing the next increment.
c. Preparation of trench bottom. The trench bottom
shall be so constructed so as to provide a firm, stable, and uniform
support for the full length of the pipe. Bell holes at each joint
shall be provided to permit the joint to be made properly.
d. Trench excavation classifications. All excavation
shall consist of two (2) classifications, vis: Class "A" and Class
"B".
(1)
Class "A" excavation. Class "A" excavation
shall consist of all other materials not mentioned in Class "B". The
decision of the City of Union shall be final on the determination
of the proper classification.
(2)
Class "B" excavation. Any material shall be
considered Class "B" excavation which, in the opinion of the City
of Union, cannot be excavated by any process other than drilling and
blasting or drilling and wedging. This classification shall not be
extended to include the materials which can be removed by other means,
but which, for reasons of economy in excavation, it is preferred to
remove by drilling and blasting or drilling and wedging. Such excavation
shall include detached pieces of rock or boulders one (1) cubic yard
or more in content and masses of solid well-defined ledges of stone
or masses of rock, slate, shale, or soapstone and other similar substances.
Class "B" excavation shall be stripped for measurement in sections
of such length as the City of Union may direct, and no rock excavated
or blasted before such measurements will be allowed. "Stripping" shall mean the removal of all other materials so as to expose the
surface of the rock.
(a)
Explosives. Explosives shall only be used of
such character and strength and in such manner as may be permitted
by the City of Union. All necessary precautions shall be taken to
prevent accidents and injury or damage to adjacent buildings. Blasts
shall be completely and carefully covered with heavy timbers or other
adequate protections and shall be made only between such hours as
may be designated by the City of Union. The contractor shall be liable
for all injuries or deaths of persons or damages to property caused
by blasting or explosives.
(b)
Measurement. All Class "B" excavation shall
be measured in place by the cubic yard. No loose, shaken or previously
blasted rock will be allowed as Class "B" excavation, nor shall any
excavation exterior to the maximum limits of measurement be allowed.
e. Stockpiling of excavated material. All excavated
material shall be stockpiled in a manner that will not endanger the
work and will avoid obstructing sidewalks and driveways. Hydrants
under pressure, valve pit covers, valve boxes, curb stop boxes, fire
and Police call boxes, or other utility controls shall be left unobstructed
and accessible until the work is completed. Gutters shall be kept
clear or other satisfactory provisions made for street drainage and
natural watercourses shall not be obstructed.
3. Laying of pipe.
a. Lowering pipe and accessories into trench.
(1)
General. Proper implements, tools and facilities
satisfactory to the City of Union shall be utilized by the contractor
for the safe and efficient execution of the work. All pipe, fittings,
valves and accessories shall be carefully lowered into the trench
using suitable equipment in such manner as to prevent damage to pipe
and fittings. Under no circumstances shall the pipe or accessories
be dropped or dumped into the trench.
(2)
Inspection of pipe and accessories. The pipe
and accessories shall be inspected for defects prior to lowering into
trenches. Any defective, damaged, or unsound material shall be repaired
or replaced as directed by the City of Union.
(3)
Pipe kept clean. All foreign matter or dirt
shall be removed from the interior of the pipe before lowering into
position in the trench. Pipe shall be kept clean by means approved
by the City of Union during and after laying.
b. Joining pipe sections. The sealing surface of the
pipe, the bell to be joined, and the rubber ring shall be cleaned
immediately before assembly, and assembly shall be made as recommended
by the manufacturer. When pipe laying is not in progress, the open
ends of installed pipe shall be closed to prevent entrance of trench
water into the line. Whenever water is excluded from the interior
of the pipe, enough backfill shall be placed on the pipe to prevent
floating. Any pipe that has floated shall be removed from the trench
and the bedding restored. No pipe shall be laid when the trench conditions
or the weather are unsuitable for proper installation as determined
by the City of Union.
c. Cutting pipe. The pipe shall be cut in a neat and
workmanlike manner without damage to the pipe so as to have a smooth
end at right angles to the axis of the pipe.
d. End preparation. Pipe ends shall be cut square and
beveled in accordance with the pipe manufacturer's recommendations.
e. Joining PVC pipe to fittings and accessories.
(1)
General. PVC pipe shall be manufactured with "iron pipe size" outside diameters. Each valve or fittings
connected to PVC plastic pipe shall be equipped with a bell having
a profile that permits a seal to be made directly between the pipe
end and the bell of the fitting with a rubber gasket. The rubber gaskets
shall be supplied by the fittings or accessory manufacturer.
(2)
Push-on joints. The push-on joint shall be
a rubber gasket joint. It shall be assembled by the positioning of
a rubber ring gasket in an annular recess in the fitting socket and
then forcing the end of the pipe into the socket. The pipe end compresses
the gasket radially to form a positive seal. The gasket and annular
recess shall be designed, sized and shaped so that the gasket is locked
in place against displacement. Care should be taken to use the correct
gasket to match the fitting gasket groove profile. Assembly of the
gasket within the groove should be in accordance with the manufacturer's
recommendations.
f. Setting of valves and fittings.
(1)
General. Valves and fittings shall be provided
and installed as shown on the approved plans as specified. They shall
be inspected and cleaned prior to installation.
(2)
Thrust blocking. Thrust blocking shall be provided
at each valve, bend, tee, and at reducers or fittings where changes
in pipe direction occurs.
4. Pressure and leakage tests.
a. General. Sufficient backfill shall be placed prior
to fillings with water and field testing to prevent lifting of the
pipe. When local conditions require that the trenches be backfilled
immediately after the pipe has been laid, the testing may be carried
out after backfilling has been completed. At least seven (7) days
shall elapse after the last concrete thrust blocking has been cast
with normal (Type I) Portland cement. This elapsed time may be reduced
to three (3) days with the use of high-early strength (Type III) Portland
cement.
b. Procedure. The following procedure is based on the
assumption that the pressure and leakage test will be performed at
the same time. Separate tests may be made if approved by the City
of Union. If separate tests are made, the pressure test shall be made
first (1st), the duration of the pressure test may be reduced to one
(1) hour and the test pressure for the leakage test may be reduced
to the maximum working pressure that will occur on that last portion
of the line. Each section of the pipeline shall be slowly filled with
water and all air expelled by means by taps at high points. The specified
test pressure shall be applied by means of a pump connected to the
pipe in a manner satisfactory to the City of Union. The test pressure
shall be maintained by additional pumpage if necessary for the specified
time during which all exposed pipe, fittings, valves and hydrants
shall be carefully examined. All defective elements shall be repaired
or removed and replaced and the test repeated until all visible leakage
has been stopped and the allowable leakage requirements have been
met.
c. Allowable leakage. The contractor shall furnish
the gauges and measuring device for the leakage test, pump, pipe,
connections and all other necessary apparatus and shall furnish the
necessary assistance to conduct the test. The duration of each leakage
test shall be two (2) hours and during the test the main shall be
subjected to the pressure required above or as specified in the purchaser's
addendum to this standard. "Leakage" shall be defined
as the quantity of water that must be supplied into the newly laid
pipe or any valved section thereof to maintain the specified leakage
test pressure after the pipe has been filled with water and the air
in the pipeline has been expelled. No installation will be accepted
if the leakage is greater than that determined by the formula:
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L = ND√P
7,400
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P = 50 psi
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L is the allowable leakage in gallons per hour; N is the number
of joints in the length of pipeline tested; D is the nominal diameter
of the pipe in inches; and P is the average test pressure during the
leakage test in pounds per square inch gauge.
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D. Backfilling.
1. Pipe bedding. Pipe shall be laid in a flat bottom
trench with backfill material approved by the City of Union deposited
in the trench uniformly at both sides of the pipeline for the full
width of the trench, up to the horizontal diameter of the pipeline.
This backfill material shall be tamped into layers and shall be sufficiently
damp to permit thorough compaction under and on each side of the pipe
to provide support free from voids. When pipe is to be laid in a trench
excavated from rock, an overdig of four (4) inches shall be maintained
and a four (4) inch thick sand layer provided to cushion the pipe.
2. Backfilling procedure before tests. If visual inspection
during the hydrostatic test is not required by the City of Union,
the pipe and joints shall be embedded as specified above and a cushion
of material placed over the pipe and joints to an average depth of
twelve (12) inches. If the joints are to be exposed during the test,
additional backfill material shall be placed between the joints in
order to hold the line securely during the test. The average depth
of material in this instance shall be twelve (12) inches over the
top of an eight (8) inch diameter and smaller pipe and twenty-four
(24) inches over larger pipe.
3. Backfill procedure after tests. On completion of
pressure and leakage tests, exposed joints shall be embedded as specified
above and backfill placed to a depth of twelve (12) inches above the
top of the pipe. The balance of backfill shall contain no stones more
than six (6) inches in their largest dimension. Trenches shall be
backfilled to a compaction density of ninety percent (90%) as determined
by the American Association of State Highway and Transportation Officials
Method T99 for Compaction and Density of Soils. Additional backfill
material shall be supplied if needed to completely backfill the trenches
or to fill depressions caused by subsequent settlement.
E. Restoration Of Surfaces And/Or Structures. The contractor
will restore and/or replace paving, curbing, sidewalks, gutters, shrubbery,
fences, sod or other disturbed surface or structure to a condition
equal to that existing before the work began and to the satisfaction
of the City of Union. Public street repairs shall be in accordance
with the requirements of the approved plans and specifications.
F. Cleaning Up. All dirt, rubbish, and excess earth from excavations
shall be disposed of by the contractor in compliance with applicable
laws and ordinances and these specifications. The construction site
shall be left clean to the satisfaction of the City of Union.
[R.O. 2012 §410.170; Ord. No. 2438 §3, 6-8-1998]
A. Pre-Cast Manholes.
1. Pre-cast manholes shall be forty-eight (48) inches in diameter and
conform with ASTM C478 and with design dimensions. Cones and sections
shall be substantially free from fractures, large or deep cracks and
surface roughness.
2. All lift holes shall be thoroughly wetted and then be completely
filled with mortar, smoothed and pointed to insure water-tightness.
3. All joints between pre-cast elements on manholes shall be made with
an approved bitumastic material or an approved rubber gasket.
4. The first (1st) pre-cast barrel section shall be positioned and carefully
adjusted to true grade and alignment. Manhole connections for inlet
pipes shall be in accordance with the approved plans. All inlet pipes
shall be properly installed with the base section so as to form an
integral water-tight unit. The base section shall be cast in place
to form a water-tight unit with the first (1st) barrel section.
5. Pre-cast sections shall be placed and aligned to provide vertical
sides and vertical alignment of the ladder rungs. The completed manholes
shall be rigid, true to dimensions, and water-tight.
6. Tops of manholes shall be built up to the elevations indicated on
the approved plans. Where no evaluation is indicated, they shall be
built to the existing ground surface unless the City of Union shall
direct otherwise.
B. Frames And Covers. Frames and covers shall be of the type
of duty shown on the approved plans. Iron castings shall conform to
the latest revision of ASTM Specifications A-48, Class 20. All castings
shall be true to pattern in forms and dimensions, free from faults,
sponginess, cracks, blowholes, and other defects affecting their strength.
Bearing surfaces between cast frames and covers shall be machined,
fitted together, and match-marked to prevent rocking.
[R.O. 2012 §410.175; Ord. No. 2842 §1, 7-14-2003]
A. Design Standards. All sanitary sewer lift stations constructed
within the City of Union, Missouri, shall be designed and constructed
in accordance with Division 20, Chapter 8 of Title 10 of the Code
of State Regulations (10 CSR20-8), a copy of which is on file in the
office of the City Engineer for the City of Union, Missouri.
B. Access. Access to all sanitary sewer lift stations constructed within the City of Union, Missouri, shall have access thereto constructed in accordance with Section
405.780 of the Code of Ordinances of the City of Union, Missouri, and such access shall be provided by means of a properly dedicated easement.