Section VI – Sewage Force Mains
PART 1 – GENERAL
1.01 WORK INCLUDED
A. The work under this Section includes providing pressure pipe and appurtenant items for sewage force mains.
B. Related Work Specified Elsewhere:
1. Section I – Trenching, Backfilling and Compacting for Utility System
2. Section III – Concrete
1.02 QUALITY ASSURANCE
A. Design Requirements:
1. Force mains shall be laid with a minimum cover of 30-inches and a maximum cover of 72-inches below finished grade, unless otherwise indicated.
2. Sewage force mains shall be constructed of the materials as set forth herein.
3. Force mains 12-inches and smaller shall be constructed of Class 200 PVC pipe with Class 350 ductile iron fittings, and mains larger than 12-inches shall be constructed of ductile iron pipe with ductile iron fittings, unless otherwise indicated.
4. Changes in vertical and horizontal alignment of less than twenty-two (22) Degrees may be achieved through use of allowable pipe joint deflection in lieu of fittings at the Contractor’s option, but subject to approval of the Engineer. Said deflection shall not exceed limits set forth in applicable AWWA Standards and/or the pipe manufacturer’s recommendation.
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B. Pipe Inspection: The Contractor shall obtain from the pipe manufacturers a certificate of inspection to the effect that the pipe and fittings supplied for this Contract have been inspected at the plant and that they meet the requirements of these specifications. All pipe and fittings shall be subjected to visual inspection at time of delivery by rail or truck, also just before they are lowered into the trench to be laid, and joints or fittings that do not conform to these specifications will be rejected and must be removed immediately by the Contractor. The entire product of any plant may be rejected when, in the opinion of the Owner, the methods of manufacture fail to secure uniform results, or where the materials used are such as to produce inferior pipe or fittings.
C. Prevention of Electrolysis:
1. Where deemed necessary, electrolytic action through the contact of dissimilar metals, shall be prevented by either:
a. The separation of one material from the other by means of an insulating or dielectric coupling, or
b. The use of alternative materials, as directed by the Engineer.
A. Shop Drawings:
1. In general, 6 copies of the following shop drawings shall be submitted to the Engineer for approval prior to construction:
a. Mill test certificates or certified test reports on pipe
b. Details of restrained and flexible joints
c. Valve vaults
d. Valves and valve boxes
e. Air release valves
f. Pipe laying schedule
g. Temporary plug and anchorage system for hydrostatic pressure test
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2. A copy of the approved shop drawings shall be sub mitted to the Owner prior to delivery of materials.
B. Record Information: Record drawings shall be prepared and submitted to Gulf Shores Utilities. These record drawings shall specifically locate via discrete, manual measurements of each and every component of the installed system, including: main line alignment and depth, transitions in main line pipe material, main line fittings, valves, air release valves, blow-offs, and any other such items or project elements as may be required. Location by triangulation measurements will be strictly enforced. Stationing of features from a remote initiation point will not be acceptable. Use of intangible features (e.g. Survey Lines, Property Lines, etc.) as a reference point will not be acceptable.
1.04 JOB CONDITIONS
A. Water in Excavation: Water shall not be allowed in the trenches while the pipes are being laid and/or tested. The Contractor shall not open more trench than the available pumping facilities are able to dewater to the satisfaction of the Engineer. The Contractor shall assume responsibility for disposing of all water so as not to injure or interfere with the normal drainage of the territory in which he is working. In no case shall the pipelines being installed be used as drains for such water, and the ends of the pipe shall be kept properly and adequately blocked during construction by the use of approved stoppers and not by improvised equipment. All necessary precautions shall be taken to prevent the entrance of mud, sand, or other obstructing matter into the pipelines. If on completion of the work any such material has entered the pipelines, it must be cleaned as directed by the Engineer so that the entire system will be left clean and unobstructed. (See Section IV-1.05).
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PART 2 – SEWER FORCE MAINS
EFFECTIVE JANUARY 1, 2014, ALL MATERIALS SHALL MEET NSF/ANSI 61 STANDARDS (LEAD FREE MATERIALS)
APPROVED PRODUCT PVC PIPE: SDR 21 CLASS 200 DUCTILE IRON PIPE: CLASS 51 FITTINGS: CLASS 350 DUCTILE IRON JOINT RESTRAINT: M.J. RETAINER GLANDS, EBBA IRON SERIES, 1100 MEGALUG GATE VALVE: RESILIENT SEAT M.J. W/2″ OPERATING NUT, MUELLER, CLOW OR AMERICAN DARLING
CHECK VALVE: TAPPING SLEEVE(PVC): STAINLESS STEEL JCM 452, JCM 459, JCM 462 or Smith-Blair 665. TAPPING SLEEVE(D.I.): JCM 452, JCM 459, JCM 462 or Smith-Blair 665
TRACING WIRE: 12 GAUGE, COATED GREEN I.D. TAPE: NON-METALLIC GREEN LABELED “SEWER LINE”
VALVE BOXES: CAST IRON VALVE MARKERS: FIBERGLASS/PLASTIC, 66″IN LENGTH MARKED “SEWER” VALVE
PIPELINE MARKERS: FIBERGLASS/PLASTIC, “66” IN LENGTH MARKED SEWER LINE
B. Ductile Iron Pipe And Fittings:
1. Ductile Iron Pipe: Ductile iron pipe shall conform to the requirements of ANSI Standard A21.51, Class 51 unless otherwise specified. Joints for ductile iron pipe shall be mechanical or push on joints, unless as otherwise specified. Pipe interior shall have polyethylene lining. Exterior of pipe shall have a bituminous coating applied by the airless spray method. Field damage to polyethylene lining shall be repaired to manufacturer’s specifications.
a. All ductile iron fittings shall be Class 350 mechanical joint or single gasket, push on type with a minimum pressure rating of 150 psi and shall conform to the requirements of ANSI Standard A21.10.
b. Mechanical joint and/or single gasket, push on type fittings shall be polyethylene lined, seal coated and outside coated as specified above for ductile iron pipe.
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PRESET LOW PRESSURE SEWER SERVICE/PRODUCT LINE
All new subdivisions shall be equipped with pre-set Low Pressure Sanitary Sewer Service for residential lots. Pre-set Low Pressure Sewer service installations shall consist of the following materials:
1″ Low Pressure Sewer Pre-Set Service
Service saddle, Ex: JCM #406-IP, Smith-Blair 317-IP or Ford FC202-IP. Epoxy Coated w/Double Stainless Steel Bale’s & Hardware. All service saddles are to be equipped with a 1″ AWWA(IP) outlet thread. Sewer Service connections established on ductile iron piping are to direct tapped utilizing a 1″ AWWA (IP) drill tap & installing a 1″ ground key corporation stop style valve.
1″ Ground Key Corporation Stop IPE, PE Mueller H-15029 or Ford F1101-4Q
1″ Curb Ball Stop IPS, PE Quarter turn check w/lock wing, Mueller B-25196 or Ford B61-444-WQ
1-1/4″ Check Valve, Bronze – Kitz #104, 1-1/4″ Bronze single swing check valve, fip x fip.
Brass Service Materials ****Domestic Source Only****
1″ x close Brass pipe nipple 1-1/4″ x 1″ Brass hex bushing reducer, mip x fip 1-1/4″ Brass tee 1-1/4″ Brass plug 1-1/4″ x close Brass pipe nipple
Service Line – 1″ IPS PET, 1″ SDR 7 IPS Pet, Driscopipe 5100 ultraline or Orangebury equivalent Service Line Color Black or Green, solid color Tubing Insert – 1″ IPS, stainless steel tubing liner – Ford #53-72 (1.049 ID) or Mueller Equivalency, #505142.
Service Valult PVC Carson Brooks Model 1220B Series CB 1220-12B(Base)color green
CB 1220-5B(Lid) color green, solid, stamped Sewer
Security Locks Highfield firomatic #6 Barrel lock & cap, stainless steel w/dust cap #6 Firomatic lock #93180128 w/dust cap #9311016
Locater Wire 12AWG, Solid green (ATTACHED TO 1″ IPS PET SERVICE LINE)
VI – 4a 3. Joints: Mechanical joints consisting of bell, socket, gland, gasket, bolts and nuts shall conform to ANSI Standard A21.11. Bolts shall be high strength, annealed, cast iron, or high strength low allow steel, T-head type having hexagonal nuts. Bolts and nuts shall be machined true and nuts shall be tapped at right angles to a smooth bearing surface. Single seal gasket push on type joints shall conform to the requirements of ANSI A21.11 and shall be “Tyton”, “Fastite”, “Super Bell Tite”, “Altite”, or approved equal.
4. Restrained Joints: Joint restraints shall be Series 1100 Megalug Ductile Iron retainer glands as manufactured by EBAA Iron.
5. Gaskets: Gaskets shall be of neoprene and shall have plain tips unless otherwise specified.
C. Polyvinyl Chloride Pipe And Fittings:
a. Polyvinyl chloride (PVC) pipe 2-inches and larger in diameter shall conform to the requirements of ASTM Designation D 2241, Class 1120 or 1220, SDR 21 for a minimum pressure rating of 200 psig at 73.4-1/4F and green in color for sewer. All PVC pipe shall bear the approval seal of the National Sanitation Foundation (NSF) for potable water pipe.
b. Polyvinyl chloride pipe smaller than 2-inches shall conform to the requirements of ASTM Designation D 1785, Class 1120 or 1220, Schedule 80 pipe with a minimum pressure rating of 400 psig. at 73.4-1/4F for unthreaded pipe.
c. All polyvinyl chloride (PVC) pipe shall be laid with 14 AWG THHN solid wire, green in color, buried one foot above and parallel to the pipe. The locator tape shall be at least two inches wide and shall be lettered, “CAUTION; SANITARY SEWER BURIED BELOW” and laid two feet above and parallel to the pipe.
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a. PVC pipe fittings 2-inches and 3-inches shall be molded and shall be furnished by the manufacturer of the pipe with which they are used and conform to the requirements of ASTM Designation D 2467. All PVC pipe shall conform to requirements of ASTM Designation D 2467. All PVC pipe fittings shall bear the approval seal of the National Sanitation Foundation (NSF) for potable water pipe.
b. Fittings for PVC pipe smaller than 2-inches shall be Schedule 80 PVC with threaded joints and conform to the requirements of ASTM Designation D 2467 and D 2464 respectively.
c. Fittings for PVC pipe 4-inches to 12-inches shall be ductile iron fittings with transition gaskets. Ductile iron fittings shall be Class 350 mechanical joint with a minimum pressure rating of 150 psi, and shall conform to the requirements of ANSI Standard A21.10.
d. All PVC pipe fittings shall bear the approval seal of the National Sanitation Foundation (NFS) for potable water pipe.
a. PVC pipe 2-inches and larger shall have provision for expansion and contraction provided in the joints. All joints shall be designed for push on make up connection. A push on joint shall be a coupling manufactured as an integral part of the pipe barrel consisting of a thickened section with an expanded bell with a groove to retain a rubber sealing ring of uniform cross section. Joints shall conform to the requirements of ASTM Designation D 3139 and provide for the pressure rating of the pipe.
b. Joints in PVC pipe smaller than 2-inches shall be threaded or push-on in accordance with the recommendations of the pipe manufacturer. Threaded joints shall be used only with Schedule 80 pipe or better. At threaded joints between PVC and metal pipes, the metal shall contain the socket end and the PVC side the spigot. A metal spigot shall not, under any circumstances, be screwed into a PVC socket.
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C. Gate Valves:
1. Gate valves 2-inches in diameter and larger shall be iron body, nonrising stem, bronze mounted resilient type gate valves, mechanical joint conforming to requirements of the AWWA Standard C509 and shall be provided with a 2-inch square operating nut. Valves shall turn to the left (counterclockwise) to open. All valves shall be provided with O-ring seals while in service without undue leakage. All valves shall be Mueller or Clow.
2. Gate valves for pipe less than 2-inches in diameter shall conform to the requirements of Federal Specifications WW-Y-54 for Class A, Type I, and shall be bronze, single wedge, nonrising stem, screwed bonnet, 125 pound S.P., 300 pound W.O.G. with stuffing box repackable under pressure and all parts renewable. Ends shall be as shown on the Drawings.
3. Valve Stem Extension: All Valves in which the operating nut is greater than 4 feet below finish grade shall be provided with extension stems to bring the operating nut to within 2 feet of the finished grade. The extension stem shall be provided with a 2-inch square operating nut on top and a coupling to connect the extension to the operating nut of the valve. A stem guide shall be provided to keep the valve stem extensions concentric with the valve box. Extension stems shall be of the same diameter as the valve stem unless otherwise specified.
D. Check Valves:
1. Swing check Valves 4-inches and larger shall have a cast iron or cast steel body with a bronze or stainless steel seat ring, non-corrosive shaft for attachment of weight and lever and a 300 psi hydrostatic test pressure rating. Check valves shall absolutely prevent the return of water back through the valve when the inlet pressure decreases below the delivery pressure. The valve must be full opening, tight seating and its seat ring shall be renewable and must be securely held in place by a threaded joint; the valve disc shall be of cast iron or cast steel and shall be suspended from a noncorrosive shaft which will pass through a stuffing box. A tapped boss with plug shall be provided on the check valve bonnet for future use with a pressure gauge. All check valves shall be Mueller or Clow with weight and lever.
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2. Check valves smaller than 4-inches shall be bronze, bronze disc, swing check valves with lever and weight conforming to Federal Specification WW-V-51E, Type 4 Class A-125 pound. Ends shall be as shown or indicated on the Drawings.
E. Valve Vaults: Valve vaults shall be of precast concrete of the type shown on the Drawings and shall conform to the applicable requirements of Section III. The cover for the nontraffic bearing vault shall be constructed of 3/16-inch steel floor plate with reinforcement or 1/4-inch aluminum diamond plate rated at 150 psi. After fabrication, the steel covers shall be galvanized by the hot dip method in conformance with the requirements of ASTM Designation A 123.
F. Valve Boxes: Cast iron valve boxes shall be provided for all valves installed underground. The valve boxes shall be adjustable to fit the designated depth of earth cover over the valve and shall be designed so as to prevent the transmission of surface loads directly to the valve or piping.
Valve boxes shall be 3 piece type and have an interior diameter of not less than 5-inches. The valve boxes shall be provided with covers marked with the word “SEWER”. The covers shall be so constructed as to prevent tipping or rattling. Boxes shall be equal to Clow Corporation No. F-2450, or Mueller Co. No. H-10357. Extension sections shall be ductile or cast iron. Each box shall have an at-grade 2′ diameter by 4″ thick protective ring constructed of Class B concrete. (See Section III)
G. Air Release Valves:
1. Automatic air release valves shall be APCO Model 400, or approved equal manufactured for sewage service. The valves shall be so designed that they will not stick shut or leak water under continued long VI – 8
Operating conditions and to insure opening under high internal pressure. The design shall incorporate a solid settling chamber or trap and a flushing system by which the trap and the entire valve can be back flushed and cleaned.
H. Concrete: Concrete shall conform to the requirements of Section III.
I. Castings: Gray iron castings for manhole frames, covers and other items shall conform to the ASTM Designation A48, Class 30. Castings shall be true to pattern in form and dimensions and free of pouring faults and other defects in positions which would impair their strength, or otherwise make them unfit for the service intended. The seating surfaces between frames and covers shall be machined to fit true. No plugging or filling will be allowed. Lifting or “pick” holes shall be provided, but shall not penetrate the cover. Casting patterns shall conform to those shown on the drawings. The words ” GULF SHORES SANITARY SEWER” shall be cast in the manhole cover. The manhole frame and cover shall be traffic bearing – Vulcan Foundry V-1418-1B, Type 2 Pick Hole or approved equal.
J. Tie Rods: Steel for tie rods and tie bolts shall conform to the requirements of ASTM Designation A 242, and rods shall be galvanized in conformance with requirements of ASTM Designation A 123. Tie rods and tie bolts shall be Super Star Tierod Figure No.SS12 and Tiebolt Figure No.SST7 respectively as manufactured by Star National Products.
K. Coal Tar Epoxy: Coal tar epoxy shall be Kopper’s Bitumastic 300M, Tnemec 46-413 Tneme-Tar or approved equal.
L. Tapping Sleeves: Tapping sleeves shall have full encirclement end gaskets so as to completely encapsulate the tap zone. Tapping sleeves shall be as manufactured by Mueller or Clow or JCM 452.
M. Additional Work: Additional items of construction, necessary for the complete installation of the systems, shall conform to specific details shown on the Drawings and shall be constructed of first-class materials conforming to the applicable portions of these specifications.
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PART 3 – EXECUTION
1. Pipe Cradle: Upon satisfactory installation of the pipe bedding material as specified in Section I, a continuous trough for the pipe barrel and recesses for the pipe bells or couplings shall be excavated by hand digging. When the pipe is laid in the prepared trench true to line and grade, the pipe barrel shall receive continuous, uniform support and no pressure will be exerted on the pipe joints from the trench bottom.
2. Cleanliness: The interior of the pipes shall be thoroughly cleaned of all foreign matter before being gently lowered into the trench and shall be kept clean during laying operations by means of plugs or other approved methods. During suspension of work for any reason at any time, a suitable stopper shall be placed in the end of the pipe last laid to prevent mud or other foreign material from entering the pipe.
1. Sewer force mains shall be installed as generally located on the plans. All fittings and valve assemblies shall be restrained to at least one full joint of ductile iron pipe in each direction. Additional joint restraint may be required in poor soil conditions. Pipe shall not be laid in trenches that contain water. Approved means, shall be used by the Contractor to assure conformance to required grade. Pipe shall not be laid in trenches that contain water. Sewer force mains shall be located a minimum of five (5) feet from any paved areas or sidewalks to allow room for service taps. Sewer force mains shall be installed with a minimum of 30 inches of cover unless groundwater is encountered. In no case shall the sewer force main be installed with less than 24 inches of cover. In areas subject to vehicular traffic, ductile iron pipe may be required.
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2. Pipe Joint Deflection: Pipe shall not be “bent” between joints to attain desired alignment. Deflection is allowable only at joints and in amounts in accordance with pipe manufacturer’s recommendations. Required deflection shall be achieved by use of appropriate fittings.
3. Rejects: Any pipe found defective shall be immediately removed and replaced with sound pipe at the Contractor’s expense.
4. Anchors: Concrete thrust blocks shall be placed at all bends, tees, plugs and other fittings to provide lateral support, except when restrained joints are specified. Thrust blocks shall conform to the details shown on the Drawings.
5. PVC: Polyvinyl chloride pipe may be damaged by prolonged exposure to direct sunlight and the Contractor shall take necessary precautions during storage and installation to avoid this damage.Pipe shall be stored under cover and sufficient backfill to shield it from the sun shall be placed as the pipe is installed.
B. Ductile Iron Pipe Joints:
1. Type: The joints of all pipelines shall be made absolutely tight. The particular joint used shall be approved by the Owner prior to installation. Where shown on the Drawings or where, in the opinion of the Owner, settlement or vibration is likely to occur, all pipe joints shall be bolted.
2. Mechanical Joints: All types of mechanical joint pipes shall be laid and jointed in full conformance with manufacturer’s recommendations, which shall be submitted to the Engineer for review and approval before work is begun. Torque wrenches set as specified in AWWA Standard C111, shall be used; or spanner type wrenches not longer than specified therein may be used without the permission of the Engineer.
3. Push On Joints: Push on joints shall be made in strict, complete compliance with the manufacturer’s recommendations. Lubricant, if required, shall be an inert, nontoxic,, water soluble compound incapable of harboring, supporting, or culturing bacterial life. Manufacturer’s recommendations shall be submitted to the Engineer for review and approval before work is begun.
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4. Restrained Joints: Joint restraints shall be Series 1100 Megalug Ductile Iron retainer glands as manufactured by EBAA Iron.
C. Polyvinyl Chloride Pipe Joints:
1. PVC pipe 2-inches and larger shall have provision for expansion and contraction provided in the joints. All joints shall be designed for push on make up connection. A push on joint shall be a coupling manufactured as an integral part of the pipe barrel consisting of a thickened section with an expanded bell with a groove to retain a rubber sealing ring of uniform cross section. Joints shall conform to the requirements of ASTM Designation D 3139 and provide for the pressure rating of the pipe.
2. Joints in PVC pipe smaller than 2-inches shall be threaded or pushed on. Threaded joints shall be used only with Schedule 80 pipe, or better. At threaded joints between PVC and metal pipes, the metal shall contain the socket end and the PVC side the spigot. A metal spigot shall not, under any circumstances, be screwed into a PVC socket.
D. Installing Valves And Boxes:
1. Valves: Valves shall be carefully inspected, opened wide and then tightly closed and the various nuts and bolts shall be tested for tightness. Special care shall be taken to prevent any foreign matter from becoming lodged in the valve seat. Valves, unless shown otherwise, shall be set with their stems vertically above the center line of the pipe. Any valve that does not operate correctly shall be removed and replaced.
2. Valve Boxes: Valve boxes shall be carefully centered over the operating nuts of the valves so as to permit a valve key to be fitted easily to the operating nut. Valve boxes shall be set to conform to the level of the finished surface and held in position by a ring of concrete placed under the support flange as shown on the Drawings. The valve box shall not transmit surface loads to the pipe or valve. Care shall be taken to prevent earth and other material from entering the valve box. Any valve box which is out of alignment or whose top does not conform to the finished ground surface shall be dug out and reset. Before final acceptance of the work all valve boxes shall be adjusted to finish grade. Valve boxes shall be of
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the appropriate length to extend from the valve to the surface when properly adjusted. No field-fabricated extensions shall be accepted. Valve box shall be centered on the operating nut of the valve and shall be held in place by a 2-foot quare concrete collar or a pre-cast collar. Valve box lids shall be marked “SEWER”. Valve markers shall be placed adjacent to each valve parallel with the pipe. Pipeline markers shall be placed parallel to the main at 500-foot intervals and each way from fittings to indicate any change in direction.
1. After pipe has been laid, inspected, and found satisfactory, sufficient backfill shall be placed along the pipe barrel to hold the pipe securely in place during the conduction of the preliminary hydrostatic test. Backfill material shall be dry and free from materials that may damage pipe(stumps, rocks, etc.) In wet conditions, select fill materials may be required. Dead end sewer force mains shall be terminated with an approve d flushing assembly. No backfill shall be placed over joints until the preliminary test is satisfactorily completed, leaving them exposed to view for the detection of visible leaks.
2. Upon satisfactory completion of the preliminary hydrostatic test, backfilling of the trench shall be completed. (See Section I)
F. Identification: All polyvinylchloride (PVC) pipe shall be laid with locator wire buried one foot above and parallel to the pipe. The locator wire shall be at least two inches wide and shall be lettered, “CAUTION: SANITARY SEWER BURIED BELOW.” 14 AWG THHN solid green will be laid two feet above and parallel to the pipe. Where transitions from PVC to DI or DI to PVC occur, provision must be made to insure continuity of locator tape/wire. Also insure continuity at fittings and valves.
G. Location In Relation To Water Lines: Refer to Section IV, Paragraph 3.02.H. Non metallic tape identifying the pipe as a sewer line shall be installed directly above the wire.
3.03 FIELD QUALITY CONTROL
A. Flushing: All force mains shall be flushed to remove all sand and other foreign matter. The velocity of the flushing water shall be at least 4-feet per second. VI – 13
Flushing shall be terminated at the direction of the Engineer. The Contractor shall dispose of the flushing water without causing a nuisance or property damage. No flushing shall be performed without approval from Gulf Shores Utilities (GSU).
B. Cleaning: Prior to pressure and leakage testing, the interior of each main shall be cleaned of accumulation of sand and other foreign matter by pressure or hand methods. Hand cleaning methods may consist of shoveling the material and pressure cleaning with a water hose. Care shall be exercised in cleaning to prevent damage to the pipe lining.
C. Hydrostatic Tests:
1. All components of the force main system, including fittings, connections and valves shall remain uncovered until tested and accepted; provided, however, that pipe trenches under traveled streets or roads or in unstable soil conditions may be backfilled with the permission of the Engineer. No testing shall be done until all concrete thrust blocking is in place and set. If high-early strength concrete is used, testing may be conducted 48 hours after the concrete is placed; otherwise thrust block concrete must cure 5 days before pressure testing commences. In testing, the part of the system under test shall be filled with water and subjected to a sustained pressure of 100 pounds per square inch. The piping may be tested in sections, thereby testing each valve for secure closure. While the system is being filled, air shall be carefully and completely exhausted. If permanent air vents are not located at all high points, the Contractor shall install corporation stops or fittings and valves at such points so the air can be expelled as the pipe system is slowly filled with water.
2. Test pressure shall be maintained for 2 hours until all sections under test have been checked for evidence of leakage. Rate of loss shall not exceed that specified hereinafter. Visible leaks shall be corrected regardless of total leakage shown by test.
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3. All pumps, gauges and measuring devices shall be furnished, installed and operated by the Contractor and all such equipment and devices and their installation shall be approved by the Engineer. Contractor shall provide a recording pressure gauge with minimum twelve inch (12″) diameter chart and certification of calibration for same. All pressure and leakage testing shall be done in the presence of a representative of the Owner.
4. Water for testing and flushing shall be potable water provided by the Contractor from a source approved by the Engineer.
5. Preliminary pressure testing may be waived by the Engineer for pipe 24-inches in diameter and larger.
D. Allowable Limits For Leakage:
1. The hydrostatic pressure tests shall be performed as hereinabove specified and no installation, or section thereof, will be acceptable until the leakage is less than the number of gallons per hour as determined by the formula:
SD % P L = ——– 133200
L = Allowable leakage, in gallons per hour S = Length of pipe being tested in feet D = Nominal pipe diameter; in inches P = Average test pressure during the test, in psi gauge. Pressure must be maintained +/- 5 psi by pump-ups. Last step in test will be to add water to verify the final pressure of 100 psi.
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2. For a 1000-foot segment of main with average test pressure of 100 psi the following table may be used.
Pipe Allowable Pipe Allowable Diameter(D) Leakage(L) Diameter(D) Leakage(L) Inches Gal./Hr. Inches Gal./Hr. ----------- ---------- ----------- ----------- 3 0.23 14 1.05 4 0.30 16 1.20 6 0.45 18 1.35 8 0.60 20 1.50 10 0.75 24 1.80 12 0.90 30 2.25
3. Water shall be supplied to the main during the test period as required to maintain the test pressure as specified. The quantity used, which shall be compared to the above allowable quantity, shall be measured by pumping from a calibrated container. A 5/8-inch meter installed on the suction side of the pump may be used to measure the leakage for large mains when approved by the Engineer.
E. Correction Of Work: Where leakage exceeds the allowable limit, as specified hereinbefore, the defective pipe or joints shall be located and repaired. If the defective portions cannot be located, the Contractor shall remove and reconstruct as much of the work as is necessary in order to conform to the specified limits. Any visible leaks or any defective pipe or joint shall be repaired or replaced as directed by the Engineer even though the total leakage is within the specified allowable limits. No additional payment will be made for the correction of defective work, or to damage to other parts of the work resulting from such corrective work.
A. Connection To Existing System:
1. All connections to existing mains shall be made to conform with the requirements and under the direction of Gulf Shores Utilities (GSU). Valves separating the mains being installed from existing mains shall be operated by or under the direction of GSU. Some connections may require night work when peak flows are not anticipated. The cost of the work in making the connections shall be paid for by the Contractor.
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2. In the event the proposed main is to be connected to a main which is in service, a temporary plug or cap shall be installed on the new main until the pressure tests are completed. Upon satisfactory completion, the cap or plug shall be removed from both mains and the connection made. The connection shall be made as swiftly as possible and any water in the ditch shall be kept below the level of the pipe. The pipeline shall then be placed in service by Gulf Shores Utilities personnel.
3. In the event any existing users will be without service while a connection is being made, the Contractor shall notify GSU of when the service will be turned off and when he estimates service will be resumed. In some instances, these connections may have to be made at night. No user shall be without service for more than two hours. In some cases, Gulf Shores Utilities may require the Contractor to provide temporary service to these affected customers.
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