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    SECTION 02663

    CLEANING AND RELINING WATER MAINS

   PART 1 GENERAL

   1.01 SECTION INCLUDES

    A. Restoration of existing water mains (4-inch and larger new and old steel, ductile iron and cast iron water pipelines that have been previously installed) by lining the mains with a machine that progresses uniformly through the pipe, applies cement mortar against the pipe surfaces and has an attachment for mechanically troweling the mortar to obtain a smooth lining of uniform thickness with smooth transitions over joints. The lining of bends, specials, and areas adjacent to valves are restored by machine sprayed and hand troweled or where machine placing is impractical, lining will be performed by hand methods.

   1.02 REFERENCES

    A. Codes, Specifications, and Standards:

    1. Codes, specifications, and standards referred to by number or title shall form a part of this specification to the extent required thereto. Latest revisions shall apply, unless otherwise shown or specified.

    2. All pipe materials incorporated in the project shall be approved by the Tennessee Department of Environmental and Conservation for the application used prior to the receipt of bids.

    B. American Society for Testing and Materials (ASTM) Standards:

    C40 Test Method for Organic Impurities in fine Aggregates for Concrete.

    C143 Standard Test Method for Slump of Portland Cement Concrete.

    C150 Standard Specifications for Portland Cement.

    C494 Standard Specifications for Chemical Admixtures for Concrete.

    C618 Standard Specifications for Fly Ash and Raw or Calcined Natural Pozzolan for Use as a Mineral Admixture in Portland Cement Concrete.

    E11 Standard Specification for Wire-Cloth Sieves for Testing Purposes.

    C. American Water Works Association (AWWA) Standards:

    C500 Standard for Gate Valves for Water and Sewerage Systems.

    C504 Standard for Rubber-Seated Butterfly Valves.

    C509 Standard for Resilient-Seated Gate Valves for Water and Sewerage Systems.

   1.03 SUBMITTALS

    A. Submit the following:

    1. Manufacturer’s Certificate of Compliance certifying compliance with the applicable specifications and standards.

    2. Certified copies of test reports of factory tests required by the applicable standards and this Section.

    3. Manufacturer’s installation instructions and procedures.

    4. Contractor’s procedures and materials for service renewal, including time and duration of water service unavailability.

   1.04 DELIVERY, STORAGE, AND HANDLING

    A. The Contractor shall be responsible for the delivery, storage, and handling of products. No products shall be shipped to the job site without the approval of the Owner’s Representative.

    B. Keep products safe from damage. Promptly remove damaged products from the job site. Replace damaged products with undamaged products.

   PART 2 - PRODUCTS

   2.01 GENERAL

    A. Except as specifically stated otherwise in this Section, all products shall conform to the applicable requirements of the AWWA Standard C602, latest revision, for Cement-Mortar Lining of Water Pipelines, 4-inch and larger, in place.

    B. The finished pipe liner shall be fabricated from materials which when complete is chemically, will withstand internal exposure and is non-hazardous to potable water systems.

    C. Field measurements of the existing pipe diameters, ovality and length shall be taken at all access points.

   2.02 CEMENT MORTAR LINING

    A. All cement mortar linings shall comply with the American Water Works Association Standard C602-89, latest revision, or the intent thereof as determined by the Engineer.

    B. The mortar for the lining shall be composed of cement, sand, and water well mixed and of proper consistency to obtain a dense homogeneous lining that will firmly remain in place on the pipe surface. The sand shall be dry bagged, not bulk, with no organics and a certified analysis of the sand shall be presented to the Engineer and Owner. Sand shall be well-graded and pass a No. 16 mesh screen with no more than 5 percent passing a No. 100 sieve. All Portland cement used in the mortar for the lining shall comply with the latest revisions of ASTM Designated C150 Type II. Only Type II Portland Cement shall be used.

    C. The cement mortar lining shall be placed by machine, the essentials of which shall be a head, revolving at high speed projecting the mortar against the wall of the pipe at a high velocity. The impelling force shall be centrifugal and no air shall be utilized in the process of mixing, conveying or application and there shall be attachments troweling a smooth surface finish to the applied mortar. The trowel arrangement shall be such that the pressure applied to the lining will be uniform and produce a smooth surface without spiral shoulders and of uniform thickness. Nothing shall come in contact with the troweled surface until it has attained its initial set.

    D. Only machines that have successfully placed cement mortar linings similar to that herein specified and which have been in service and proved satisfactory for at least three (3) years will be acceptable.

    E. Acceptable C-factor (Hazen-Williams Coefficient)

    1. The cement-mortar lined pipe shall yield the following C Factor:

    Pipe Inside Diameter C-Factor

    in (mm)

    4 (100) 90

    6 (150) 100

    8 (200) 110

    10 (250) 115

    12 (300) 120

    14-20 (350-500) 125

    >20 (>500) 130

    F. The Thickness of the cement-mortar lined pipe must at least conform to the following table:

   Type of Pipe (US Customary Units)

    Old and New Cast Iron

    Old Steel and Ductile Iron New Steel

   Nominal

   Nominal

   Nominal

   Nominal

   Nominal

   Nominal

   Diameter

   Thickness

   Diameter

   Thickness

   Diameter

   Thickness

   In.

   of Lining*

   In.

   of Lining*

   In.

   of Lining*

   In.

   In.

   In.

   4-12

   1/4

   4-10

   1/8

   4-12

   3/16

   14-22

   5/16

   12-36

   3/16

   14-36

   1/4

   24-60

   3/8

   >36

   1/4

   42-60

   3/8

   >60

   1/2

   66-90

   7/16

   >90

   1/2

   Type of Pipe (Metric Units)

    Old and New Cast Iron

    Old Steel and Ductile Iron New Steel

   Nominal

   Nominal

   Nominal

   Nominal

   Nominal

   Nominal

   Diameter

   Thickness

   Diameter

   Thickness

   Diameter

   Thickness

   mm

   of Lining*

   mm

   of Lining*

   mm

   of Lining*

   mm

    mm

   mm

   100-300

   6.4

   100-250

   3.2

   100-300

   4.8

   350-500

   7.9

   300-900

   4.8

   350-900

   6.4

   600-1500

   9.5

   >900

   6.4

   1050-1500

   9.5

   >1500

   12.7

   1700-2300

   11.1

   >2300

   12.7

    *For badly deteriorated pipe or abnormal use, the purchaser should specify such greater thickness of lining as engineering judgment indicates. In all instances, tolerance for lining thickness shall be +1/8 in. (+3.2 mm) with no minus tolerance.

   PART 3 - EXECUTION

   3.01 PREPARATION

    A. Cleaning the Water Main

    1. The interior surfaces of the pipe to be lined shall be cleaned by hand cleaning, with a mechanical cleaning machine, hydraulic cleaning machine, approved by the Engineer or Owner. The cleaning method must remove: corrosion products; chemical or other deposits; loose and deteriorated remains of old coating materials; oil; grease; and accumulations of water, dirt and debris.

    2. The contractor shall take precautions against the obstructions of lateral pipe lines and service connections with debris from cleaning operations, and will be required to restore to normal conditions any pipes so obstructed. After the cleaning operation, the Contractor and the Engineer shall determine whether the pipe is sufficiently clean and whether any repairs to the pipe are required prior to the application of the cement mortar lining.

    B. Live Inspection

    1. All joints must be inspected prior to lining, and any separated joints shall be packed with the cement mortar grout to enhance a smooth finished liner.

    2. Any defective section of pipe shall not be lined with the cement mortar until it has been repaired by the Owner or released to the Contractor by the Owner.

    C. Temporary Bypass to Customers

    1. Temporary bypass facilities must be performed to customers connected to the water main being cleaned and lined. It is the responsibility of the Contractor to provide this service. The Contractor must design the system and provide service to the customers and provide temporary fire hydrants.

    Depending on the service requirements the bypass line may be laid above ground and in diameters of 2 inch, 4 inch, 6 inch, or larger if needed to supply the existing operating pressure.

    D. Obstructions

    It is intended that all fittings and other obstructions to the free passage of the lining machine are shown on the plans. When obstruction are encountered which are not shown on the plans, it will be the Contractor’s responsibility to free such obstructions.

   3.02 INSTALLATION

    A. Prior to lining, the Contractor must supply the results of the slump test to the Engineer. The results must comply with the ASTM Standard C143.

    The lining shall be applied in one course or more by a machine traveling through the pipe and distributing the mortar uniformly across the full section and long radius bends of the pipe. The discharge shall be from the rear of the machine so that the newly applied mortar will not be marked. The rate of travel of the machine and the rate of mortar discharge shall be mechanically regulated to produce a smooth surface and uniform thickness throughout. The mortar shall be densely packed and adhere where ever applied. There shall be no injuries rebound.

    B. In pipe 24 inch and larger in diameter, where machine placing of cement-mortar lining is impractical (such as sharp bends, specials, or areas closely adjacent to valves), lining shall be performed by hand. The cement mortar for handwork must be the same material as the mortar for machine placed lining.

    C. The mortar lining shall be trowled as specified in Section 2.02 C of this section. The troweling must produce a smooth surface without spiral shoulders and it must produce uniform thickness. There may be places where mechanical troweling is not practical, in such a case hand troweling is allowed. All hand finishing work in a section of pipeline shall be completed within 24 hours after completion of the machine application of mortar lining to that section.

    D. For pipes less than 24 inches in diameter, after the mortar lining has been placed but before it takes final set, laterals and services 2 inches and smaller in diameter shall be cleared by backflushing with air or water wherever necessary or as required by the Owner. The backflushing shall be accomplished in a manner that will not damage the freshly applied lining. Unless it is to be cleaned and lined, no lateral shall be excavated.

    The Contractor shall clean all interior surfaces of main-line valves after the lining machine has passed. The Contractor may, with the Owner’s approval, remove the bonnets and gates from main-line gate valves to accomplish the cleaning. The Bonnets and gates shall then be replaced. The Contractor shall, with the Owner’s approval, remove all butterfly valves from the main-line when necessitated by the operations and then reinstall them after the lining operation. New bolts and gaskets for bonnet or valve replacement meeting the requirements of the applicable AWWA valve standard (AWWA C500, AWWA C504, or AWWA C509) shall be supplied by the Contractor, unless otherwise provided.

    E. For pipes 24 inch and larger in diameter, before the lining is placed, the opening in the water main leading to air valves, blowoffs, manholes, and appurtenances, as well as to laterals and connections from the water main, shall be temporarily covered or plugged with suitable devices.

    These shall be removed later without damaging the cement mortar. When working inside the pipe is impractical, the Contractor may clear connecting pipelines by flushing and with the Owner’s approval, clean gate valves by removing bonnets and gates. The Contractor shall remove all butterfly valves from the main line when operations necessitate such removal. New bolts and gaskets for bonnet or valve replacement that meet the requirements of the applicable AWWA valve standard shall be supplied by the Contractor, unless otherwise provided.

   3.03 POST INSTALLATION (CURING)

    A. Curing operation must begin immediately after completion of the cement mortar lining and hand finishing of a section of the pipeline. The pipe shall be closed and a moist atmosphere must be maintained in this section of the pipeline to keep the lining damp and to prevent evaporation of the water from the mortar lining. All curing must be in accordance with AWWA C602-89, latest revision, Section 4.7, Curing.

    B. The Contractor shall be responsible for careful curing of the mortar lining until the section is filled with water by the Owner, or until the lining has been accepted by the Owner, but in no case more than seven days. If the Owner cannot fill the pipeline within seven days after the lining has been placed, the Owner may direct the Contractor to extend the curing period.

    C. The mortar lined pipe shall be filled with water as soon as possible, however, care must be taken not to damage the liner, and no pressure should be imposed on the liner for at least 24 hours. The filling of the mortar lined pipe shall be done by the Owner.

    D. The exterior surface of pipe exposed to sunlight shall be sprinkled with water in the daytime during the period of lining, finishing, and curing when such sprinkling is required, as determined by the Contractor, to prevent cracking of the liner.

   3.04 TESTING

    A. After installation is complete, the following tests must be completed the at Contractor’s expense prior to the Owner’s acceptance.

    1. Pressure Test - As defined in Section 02660, 3.2, B of this document.

    2. Leakage Test - As defined in Section 02660, 3.2, C of this document.

    3. Bacteriological Water Sample Test - As defined in Section 02660, 3.2, D, 5 of this document.

    4. Lining Thickness Test - The thickness of the liner must be measured at every construction access point at the 12, 3, 6 and 9 o’clock position prior to curing and must conform to the table in 2.02 F of this section.

    5. Hazen Williams Coefficient (C-Factor) Test. - The flow test must be conducted by an independent testing firm and the results must conform at least to the standard of 2.02, E of this section. If more than one section is tested in a continuous stretch, a weighted average by length may be computed for means of determining the coefficient.

   3.05 RECORDS

    The Contractor shall furnish to the Owner:

    A. A certified copy from the manufacturer of the laboratory test report of the chemical and physical analysis of the Type II cement and natural cement of pozzolonic material.

    B. An analysis of the sand to show conformity with the specifications.

    C. A written record when cement mortar lining is applied which shall show:

    1. Location of Work.

    2. Diameter of pipe lined.

    3. Linear feet of pipe lined.

    4. Slump test results.

    5. Pressure test results.

    6. Leakage test results.

    7. Bacteriological water sample test.

    8. Hazen Williams Coefficient.

   3.06 CLEAN-UP

    After the installation work has been completed and all testing acceptable, the Contractor shall clean up the entire project area and return the ground cover to grade. All excess material and debris not incorporated into the permanent installation shall be disposed of by the Contractor. Easement, sidewalks, and street surfaces shall be restored as specified or to the original condition.

   3.07 PATENTS

    The Contractor shall warrant and save harmless the Owner and Engineer against all claims for patent infringement and any loss resulting therefrom.

   END OF SECTION