§ 6.4. Execution.

6.4.1 Pipeline installation.

1)

Proper and suitable tools and appliances for safe and convenient handling and laying of pipe and fittings shall be used. Great care shall be taken to prevent the pipe coating from being damaged particularly cement linings on the inside of the pipes and fittings. Any damage shall be remedied as directed.

2)

All pipe and fittings shall be carefully examined by the contractor for defects just before laying and no pipe or fitting shall be laid which is defective. If any defective pipe or fitting is discovered after having been laid, it shall be removed and replaced in a satisfactory manner with a sound pipe or fitting by the contractor at his own expense.

3)

No pipe shall be laid in water. The contractor will be required to operate pumps, if necessary, to remove water (whether from ground or surface sources) from the trench while pipe is being laid and joints are being made. When work is not in progress the ends of the pipe shall be closed to prevent water or other foreign material from entering the pipe. Valves installed on existing mains shall be kept closed until after the line is tested, disinfected, and accepted for service.

4)

Pipe laid in trenches shall be laid true to line and grade on a firm and even bearing for its full length at depths and grades as indicated. Adequate precautions shall be taken to prevent floatation of pipelines prior to backfilling. Installation of ductile iron pipe in underground pressure piping systems shall conform to the requirements of AWWA C600. Excavation of trenches and backfilling around pipes shall conform to the requirements of the section entitled "Excavation, Trenching and Backfilling" of these regulations.

5)

All water mains shall have a minimum of 48 inches of cover above the top of the pipe or 48 inches below edge of pavement, whichever is greater.

6)

Water mains shall maintain a minimum of ten feet edge-to-edge horizontal separation from sewer lines, whether gravity or pressure. If the main cannot be installed in the prescribed easement or right-of-way and provide the ten feet separation, the separation may be reduced provided the bottom of the water main has a minimum vertical separation of 18 inches above the top of the sewer. Should neither of these two separation criteria be possible, the water main shall be installed below the sewer with a minimum vertical separation of 18 inches. Where waterline cross under gravity sewer lines, encase sewer line fully in concrete for a distance of at least ten feet on each side of the crossing. Lay water line which cross sewer force mains and inverted siphons at least two feet above these sewer lines; when joints in the sewer line are closer than three feet horizontally from the water line, encase these joints in concrete. Do not lay waterline in the same trench with gas lines, fuel lines or electric wiring. No water main shall pass through or come in contact with any part of a sanitary sewer manhole.

7)

All elbows, tees, branches, crosses, and reducers in pressure piping systems shall be adequately restrained against thrust. Underground pressure piping containing unharnessed push-on or mechanical joints or expansion joints shall be restrained by thrust blocks. The contractor may use forms or earth walls to mold the thrust blocks. When earth walls are used, they shall be cut true to shape and all excess earth removed. The work shall be conducted so that no loose earth will become mixed with the concrete. At the end of 24 hours, damp earth may be placed over the concrete to retain moisture.

8)

All lumps, blisters, excess coating, dirt and other objectionable substances shall be removed from the bells and spigots. Bells and spigots shall be wiped clean and dry. Bells shall be centered in the trench and spigots driven home.

9)

The contractor shall keep a transit and appurtenances on the job to be used for laying out the angles required for making bends and other works of this nature.

10)

Add casing to all roads with transversing waterlines.

11)

Bends, valves and other points where deemed necessary shall be blocked and harnessed to resist thrust. This shall be accomplished by methods and means approved by the department. All forms used to form concrete for blocking shall be removed before backfilling. All fire hydrants shall be harnessed as directed by the department and concrete blocking will be required to resist the thrust on fire hydrants. All stress points and ends of mains shall be inspected before backfilling.

12)

Blow-off valves shall be installed at terminus of all dead end mains. Method of installation shall be approved by the department. Refer to standard details for two-inch blow-off details.

13)

Whenever pipe requires cutting to fit the lines or install fittings, the work shall be done in such manner as to leave a smooth end at right angles to the axis of the pipe. Special care shall be exercised to guard against breaking or splitting the existing piping.

14)

All cutting of ductile iron pipe shall be done with a cutting saw. All burrs shall be removed from the inside and outside edges of all cut pipe.

15)

Mechanical joints and restrained joints shall be made in strict accordance with the pipe manufacturer's instructions. The gaskets and follower rings shall be kept clean and carefully centered in the bell with the bolts and boltholes always parallel with the centerline of the pipe. The coating and lining of the pipe shall not be damaged. The nuts on all bolts shall be started and tightened evenly around the entire circumference of the pipe. No one nut shall be tightened more than ½ turn tighter than the remainder of the nuts of the joint. When the joint is complete, the follower ring shall be equal distance from (parallel with) the face of the bell. Bolts shall not be over-stressed and shall be tightened just enough to compress the gasket sufficient to prevent leakage. Just prior to assembly, the gasket shall be cleaned of all foreign material and shall be brushed with soapy water just before slipping the gasket over the spigot and into the bell of the pipes. The joint shall be in straight alignment during assembly. Any deflection required shall be made after assembly but before tightening bolts. Bolts shall be tightened with torque wrenches with the following torque loads applied:

Range of Torque

Bolt Size (inches)	Foot Pounds
5/8	45—60
¾	75—90
1	100—120
1¼	120—150

 

16)

Push-on type joints shall be made in strict accordance with the pipe manufacturer's instructions. All joints shall be completely "belled-up" and all spigots shall be "home". The gasket seat in the socket, the gasket and the plain end of the pipe to be entered shall be wiped clean before assembly. After the gasket has been inserted into the gasket recess, a thin film of lubricant shall be applied to the inside surface of the gasket and to the outside surface of the spigot end of the pipe to be jointed. After lubricating, the end of the pipe shall not be allowed to touch the bottom or side of the trench causing dirt to adhere to the joint surface. When pipe is cut in the field, the cut end of the pipe shall be beveled with a file or grinder. The joint shall be in straight alignment while pushing the pipe to make assembly. Any deflection required shall be made after the joint is assembled.

17)

Set screw type retainer glands shall be installed in strict accordance with the fitting manufacturer's instructions. After making up the mechanical joint as previously specified, the set screws shall be run down until they are in firm contact with the pipe. The set screws shall then be tightened once completely around the joint to approximately 40 foot-pounds torque. Finally, the set screws shall be tightened twice completely around the joint to the following torques, unless a "break-away" torque is used:

Three inches through 12 inches glands - 80 foot - pounds

14 inches through 24 inches glands - 65 foot - pounds

18)

Wedge type retainer glands shall be installed in strict accordance with the manufacturer's instructions. Impact wrenches shall be prohibited for used with "break-away" nuts for final tightening.

19)

Retainer gland joints shall be made in straight alignment and any deflection required shall be made before tightening the joint bolts or set screws.

20)

Deflection of any pipe at joints for long radius curves or for avoiding obstacles shall be permitted only upon approval of the department.

21)

Where deflection of joints is permitted, such deflection shall be made in accordance with manufacturer's recommendations.

6.4.2 Connections to water mains.

1)

Connections shall be made to existing pipe lines in accordance with instructions from the water, sewer and environmental services department.

2)

Before laying pipe, locate the points of connection to existing water mains and uncover as necessary for the department to confirm the nature of the connection to be made.

3)

Interruption of services - Make connections to existing water mains only when system operations permit. Operate existing valves only with the specific authorization and direct supervision of the department.

4)

Tapping sleeves:

(a)

Prior to attaching the sleeve, the pipe shall be thoroughly cleaned, utilizing a brush and rag, as required.

(b)

Before performing field machine cut, the water tightness of the sleeve assembly shall be pressure tested. The interior of the assembly shall be filled with water. An air compressor shall be attached, which will induce a test pressure as specified in this article. No leakage shall be permitted for a period of five minutes.

(c)

After attaching the sleeve to an existing main, but prior to making the tap, the interior of the assembly shall be disinfected. All surfaces to be exposed to potable water shall be swabbed or sprayed with a one-percent hypochlorite solution.

5)

Connecting to existing side street mains:

(a)

Before taking existing side street mains out of service, taps for air removal shall be made at each high point along the section of existing main to be temporarily taken out of service. With the department's approval at each location, existing service lines may be used to expel air.

(b)

Close service line curb stops along the section or sections that will be dewatered and close all connecting main valves.

(c)

Take existing main out of service, cut and complete connection as detailed on the standard details.

(d)

Open appropriate valve and after expelling all air, return existing main to service and re-open all service line curb stops.

(e)

At all taps to remove air, install brass cap on corporation stop, backfill, and replace pavement where required.

6.4.3 Hydrant installation.

1)

Prior to installation, inspect all hydrants for direction of opening, nozzle threading, operating nut and cap nut dimensions, tightness of pressure-containing bolting, cleanliness of inlet elbow, handling damage and cracks. Defective hydrants shall be corrected or held for inspection by the department.

2)

All hydrants shall stand plumb and shall have their nozzles parallel with or at right angles to the roadway, with pumper nozzle facing the roadway, except that hydrants having two-hose nozzles 90 degrees apart shall be set with each nozzle facing the roadway at an angle of 45 degrees.

3)

Hydrants shall be set to the established grade, with the centerline of the lowest nozzle at least 18 inches above the ground or as directed by the department.

4)

Each hydrant shall be connected to the main with a hydrant tee or a six-inch branch.

5)

Hydrants shall be located as shown on the standard details or as directed by the department.

6)

Fire hydrants shall be installed at property line not to exceed five-feet maximum distance from water main, unless approved by the department.

7)

Hydrants shall be placed on ground in accordance with the standard details.

6.4.4 Valve and fitting installation.

1)

Prior to installation, valves shall be inspected for direction of opening, number of turns to open, freedom of operation, tightness of pressure-containing bolting and test plugs, cleanliness of valve ports and especially seating surfaces, handling damage and cracks. Defective valves shall be corrected or held for inspection by the department. Valves shall be closed before being installed.

2)

Valves, fittings, plugs and caps shall be set and joined to the pipe except that 12 inch and larger valves shall be provided with special support, such as treated timbers, crushed stone, concrete pads or a sufficiently tamped trench bottom so that the pipe will not be required to support the weight of the valve. Valves shall be installed in the closed position.

3)

A valve box shall be provided on each underground valve. They shall be carefully set, centered exactly over the operating nut and truly plumbed. The valve box shall not transmit shock or stress to the valve. The bottom flange of the lower belled portion of the box shall be placed below the valve operating nut. This flange shall be set on brick, so arranged that the weight of the valve box and superimposed loads will bear on the base and not on the valve or pipe. Extension stems shall be installed where depth of bury places the operating nut in excess of 30 inches beneath finished grade so as to set the top of the operating nut 30 inches below finished grade. The valve box cover shall be flush with the surface of the finished area or such other level as directed by the department.

4)

If valve boxes are installed concurrently with valves, the contractor shall be responsible for maintaining valve boxes until the warranty period expires. All lost or damaged valve boxes shall be replaced by the contractor, at the contractor's own expense.

5)

A concrete pad shall be required around each valve box, the top flush with the cover as detailed on the standard details. Precast valve pads will only be allowed where approved by the department. Precast pads shall not be used on slopes or in ditches.

6)

In no case shall valves be used to bring misaligned pipe into alignment during installation. Pipe shall be supported in such a manner as to prevent stress on the valve.

7)

Where main valves are shown on the standard details adjacent to fire hydrant tees or intersection tees, install the valves no more than four feet from the tee unless shown or specified otherwise.

8)

Nonrestrained and push-on joints shall not be installed within 15 feet of restrained joints at valves or fittings, unless shown otherwise on the standard details or approved by the department.

6.4.5 Jack and bore.

1)

The contractor shall provide to the department, for approval, a detailed plan for the methods proposed for the construction of the casing. These plans shall include the methods proposed for groundwater control and face protection.

2)

In general, jack and bore operations shall conform to the requirements of the Georgia Department of Transportation as presented in their Standard Specifications for the Construction of Roads and Bridges , latest edition. If a conflict between these regulations and the Georgia Department of Transportation Specifications exists, the more stringent specifications shall govern.

3)

Install the steel casing pipe by the dry boring method. Bore the hole and install the casing through the soil simultaneously by a cutting head on a continuous auger mounted inside the casing pipe. Fully weld lengths of casing pipe to the preceding section in accordance with AWS recommended procedures. After the boring and installation of the casing is complete, install a cleaning plug on the rig and clean the casing.

4)

After construction of the casing is complete, and has been accepted, install the pipeline in accordance with the detailed standard details and/or these regulations.

5)

Check the alignment and grade of the casing and prepare plan for approval to set the carrier pipe at proper alignment, grade and elevation. The carrier pipe shall be supported by stainless steel casing spacers to preclude movement within the casing. One spacer shall be placed not more than two feet from each end of the casing. Subsequent spacers shall be placed at six feet - ten feet intervals within the casing.

6)

Provide all necessary bracing, bulkheads, and shields to ensure complete safety to all traffic at all times during the work. Perform the work in such a manner as to not permanently damage the roadbed or interfere with normal traffic over it.

7)

Begin the boring operation in a pit, sheeted and shored as necessary and begin at and proceed from one end. Observe all applicable requirements of Georgia DOT regulations.

8)

Conduct the operations in such a manner that all work will be performed below the level of the roadbed. Coordinate and schedule all of the work with Georgia DOT.

9)

Complete all boring work at one particular location before boring work is started at another location.

10)

If the casing installation work is being conducted in an unsafe manner or in a manner detrimental to the overpassing roadway or to the safety of the traveling public, all operations of boring shall cease until the necessary corrections have been made. In the event that distress occurs to the roadway due to the boring, the contractor shall be required to submit a plan to repair the roadway. The plan must be acceptable to the Georgia Department of Transportation and the Paulding County Water, Sewer and Environmental Services Department.

6.4.6 Free boring.

1)

The contractor may construct a driveway crossing by the free bore method, in lieu of making a pavement cut, where indicated on the standard details and approved by the department. The free bore method shall be accomplished by the dry auger boring method without jetting, sluicing, or wet boring.

2)

The diameter of the free bore shall not exceed the pipe bell outside diameter or the pipe barrel outside diameter plus one inch, whichever is greater.

3)

Free boring is allowable only under residential driveways. Free boring is not allowed under commercial driveways or any roadway.

4)

The contractor shall be responsible for any settlement of the driveway caused by the free bore construction activities.

5)

If the contractor elects to free bore and an acceptable installation does not result for any reason, the contractor shall install a casing pipe by the bore and jack method.

6.4.7 Double check backflow preventers.

1)

A double check backflow preventer shall be provided immediately downstream from the customer's water meter. The backflow preventer shall be housed in the same meter box or vault as per the detail.

2)

One and one-half inch and smaller backflow preventers require a minimum of six inches below, eight inches behind, eight inches in front of, and three inches above the highest point on the device or its valves.

3)

Two-inch and larger backflow preventers require a minimum of 12 inches below, 12 inches behind, 24 inches in front of and three inches above the highest point on the device or its shut off valves.

4)

A minimum of six inches between the pit walls and the large device's valves and three inches between the pit walls and the valves on the small devices is required.

5)

The dimensions given above assume a standard "shallow" installation. If the depth exceeds 12 inches to the top of the device the other dimensions will need to be increased accordingly and be approved by the department.

6.4.8 Double detector check valve assemblies.

1)

A double detector check valve assembly shall be installed in all fire mains and fire sprinkler service lines as close to the system main as is possible. The backflow prevention assembly shall be housed in an approximately sized vault.

2)

Typically, a minimum of 12 inches below, 12 inches behind, 24 inches in front of and three inches above the highest point on the device or its shut off valves is required.

3)

A minimum of six inches shall be provided between the pit walls and the outside edge of the devices' shut off valves.

4)

The dimensions given above assume a standard "shallow" installation. If the depth exceeds 12-inches to the top of the device the other dimensions will need to be increased accordingly and be approved by the department.

6.4.9 Water meters and service lines.

1)

A water service connection shall consist of a corporation tapped into the main, a service line to a curb stop inside a meter box, a meter backflow preventer and meter set fittings.

2)

All service lines crossing under existing pavement shall be installed by boring. All service line taps shall be made with system pressure on the main and any visible leaks shall be repaired. After each meter service has been completed, the entire assembly shall be flushed to remove any foreign matter. All service lines shall have a minimum bury depth of 48 inches under ditches and shoulders, and 48 inches under the roadway.

6.4.10 Locator wire.

1)

A continuous or properly spliced Number 14 AWG THHN solid plastic coated copper wire shall be placed along all approved C900 PVC pipe installations.

2)

Care shall be taken during backfilling to prevent damaging or cutting of the locator wire.

3)

All splices shall be made by using copper wire "U" bolt assemblies and then wrapping with electrical tape.

4)

Wire shall be wrapped around pipe such that at least four "wraps" are produced per length of pipe.

5)

In lieu of "wrapping", the tracer wire may be strung along the top of pipe provided it is taped to the pipe every five feet to ensure proper positioning during backfilling.

6)

Locator wire shall be brought up to ground surface to all valve boxes and fire hydrants.

6.4.11 Valve markers.

1)

Markers shall be installed with the top of the marker protruding 36 inches above the ground surface. Valve markers shall be located in a suitable location approved by the department's inspector during construction.

2)

A marker shall be located within 20 feet or less from all in-line valves and/or taping valves. One marker may be used to reference the location of more than one valve provided the valves are within 20 feet of the marker. No marker is to be installed within three feet of direct line of operation of a fire hydrant. Valve marker shall be installed in ditch line being in direct line with water main.

3)

The brass disc shall be stamped with the distance between the valve(s) and marker. The marker shall be installed such that the disc faces the valve.

6.4.12 Field pressure testing.

1)

After the pipe has been installed, the complete pipeline shall be subjected to a hydrostatic pressure test.

2)

Except as hereinafter allowed, the line shall be tested in sections not to exceed the distance from one line valve to the next adjacent line valve. Testing two sections through an open intermediate valve will not be allowed unless adjacent line valves are less than 300 feet apart. In no case will leakage from two or more adjacent sections be "averaged" to determine that the total section meets the leakage test. Each section of line or valved section of the line shall be tested as follows:

(a)

At all high points, where air release valves or fire hydrants have not been installed, the contractor shall install corporation cocks to expel the air as the pipe is being slowly filled with water. After the pressure and disinfecting tests have been completed, the corporation cocks shall be capped with brass caps and left in place. The location of said corporation cocks shall be marked on record standard details with dimensions measured from three permanent structures.

(b)

A test pump shall be installed at the low point of the section being tested and the pipe shall be slowly filled with water.

(c)

After expelling all air at the high point, the corporation cocks shall be closed and the pressure increased to the required pressure at the test pump location. The test pressure shall be maintained within five psi for the duration of the test.

(d)

The volume of water required by the test pump to maintain this excess pressure, which will represent the leakage, shall not exceed 0.14 gallons per hour per inch diameter per 1,000 feet of pipe.

(e)

Excess pressure and leakage test shall be successfully conducted for not less than two consecutive hours. Provide an accurate pressure gage with graduation not greater than five psi.

(f)

The contractor shall, at his own expense, locate and make repairs as necessary until the leakage is within the specified allowance.

(g)

All visible leaks shall be repaired regardless of the amount of leakage.

3)

The contractor shall furnish all labor, equipment, and material necessary to conduct tests, and shall furnish and install all temporary plugs and valves necessary to isolate the test sections. Water for test purposes will be furnished by the department.

6.4.13 Disinfecting pipelines.

1)

After successfully pressure testing each pipeline section, disinfect in accordance with AWWA C 651 for the continuous-feed method and these regulations.

2)

Chlorination:

(a)

Apply chlorine solution into the new water main. Retain chlorinated water for 24 hours minimum.

(b)

After 24 hours, the contractor shall obtain samples at every outlet. Samples of water shall contain at least 25 milligrams per liter free chlorine. Re-chlorinated if required results are not obtained on all samples.

3)

Disposal of chlorinated water. Reduce chlorine residual of disinfection water to less than one milligram per liter if discharged directly to a body of water, or to less than two milligrams per liter if discharged onto the ground prior to disposal. Treat water with sulfur dioxide or other reducing chemicals to neutralize chlorine residual. Flush all lines until residual is equal to existing system.

4)

Bacteriological testing. After final flushing and before the main is placed into service, the contractor shall collect samples from the line to have tested for bacteriological quality. Testing shall be performed by the contractor at a laboratory certified by the State of Georgia. Re-chlorinate lines until the required results are obtained. Contractor shall open all valves being a part of the system being tested upon approval of bacteriological testing.

6.4.14 Guarantee against taste, odor or color. The contractor shall guarantee for a period of one year against taste, odor or color caused by pipe lining materials. The contractor shall at his own expense provide all necessary treatment to counteract any such taste, odor, or color. Bonafide complaints of taste, odor, or color in the area served by the new mains shall be deemed caused by pipe lining materials.