Paulding County › Unified Development Ordinance
Title 3 — Development Regulations, Chapter 460 — Water Design and Construction.
§ 460-10
General
460-10.01 Reference Documents and Standards.
This section provides the minimum guidelines for the design and construction of water transmission and distribution systems. The latest editions of the following specifications, standards and publications setting the minimum requirements for quality, safety and performance of work and materials form a part of these regulations as though fully repeated herein. The method of design and/or construction shall be in accordance with these Design and Construction Standards and Specifications and the following:
A.Georgia Rules for Safe Drinking Water Chapter 391-3-5 promulgated under the Georgia Safe Drinking Water Act of 1977 – O.C.G.A. 12-5-170
B.Georgia Environmental Protection Division Minimum Standards for Public Water Systems, Latest Edition
C.American Association of State Highway and Transportation Officials (AASHTO) Green Book, Latest Edition
D.American Concrete Institute (ACI) Standards, latest editions
E.American Society of Testing Materials (ASTM)
F.American National Standards Institute (ANSI)
G.American Water Works Association (AWWA)
H.Manual on Uniform Traffic Control Devices, latest editions
I.Occupational Safety and Health Administration (OSHA)
J.Applicable Federal, State and Local Requirements
460-10.02 Conflicts.
In the event of conflicts among the various sources cited above, the most stringent criteria shall take precedence. See Section 460-40.
§ 460-20
Design Flows
Each water system component shall be designed to meet certain flow requirements to ensure that water will be available in adequate quantities to meet demand characteristics throughout the system. The various flow requirements are described below.
460-20.01 Annual Average Daily Flow (AADF).
The average daily demand expresses the average amount of water used in a system during an average day. One Equivalent Residential Unit (ERU) is the equivalent demand that can be expected for one residential connection. The AADF shall be 350 gallons per day per ERU.
460-20.02 Maximum Daily Flow (MDF).
The maximum daily demand expresses the maximum amount of water used in a system in one day during peak demand. Normally expressed in gallons per day, the MDF is normally used in the design of water production and storage facilities.
460-20.03 Peak Hourly Flow (PHF).
The peak hourly demand expresses the maximum amount of water used in any hour during a day. Normally expressed in gallons per minute, PHF is used, in conjunction with fire flow requirements, in the design of water distribution systems.
460-20.04 Fire Flow Requirements.
A minimum fire flow of 1000 gallons per minute for two hours with an absolute minimum residual pressure of 20 psi at the fire hydrant shall be required. However, the fire flow required is based on the nature, type and location of the development and the minimum flow may be upwardly adjusted based upon the written recommendation of the Paulding County Fire Marshall setting forth any special conditions of the development which require additional flow. Designs should be in accordance with Paulding County Fire Marshall requirements.
460-20.05 Design Pressure.
The water distribution system shall be designed to maintain a minimum pressure of 35 PSI at ground level at all points in the distribution system and a maximum pressure of 150 psi. Pressure reducing valve (PRV) installations are used to control pressures within distribution systems. When water main extension plans are submitted for review, PRVs needed for the development are to be included on the plans with the elevation and the upstream and downstream hydraulic grade line and pressure.
§ 460-30
Sizing of Water Mains
Water distribution systems must be designed to maintain an absolute minimum residual pressure of at least 20 psi at each service connection and at all points in the distribution system under all conditions of flow, including fire flow. All construction plan submittals shall be accompanied by a hydraulic analysis prepared by a Professional Engineer registered in the State of Georgia, demonstrating compliance with these design and construction standards and specifications. The hydraulic analysis shall clearly state the basis for the design flows.
460-30.01 Major Transmission Mains.
The size of major transmission mains or extensions to such mains, throughout the system shall be in accordance with Paulding County Water Master Plan, latest revision found at http://www.paulding.gov/226/Documents-Forms-Links
460-30.02 Distribution Mains.
A.The minimum water main size in residential subdivisions to which fire hydrants are connected shall be eight inches in diameter. Subdivisions with two points of access shall be designed with two feeds from a distribution main external to the project. In cases where two points of access are not available, the size of the single main extension serving the development must be verified in the hydraulic analysis.
B.Distribution mains of six inches in diameter will be considered on a dead end with no more than five ERU's being served.
460-30.03 Velocities in Water Mains.
The hydraulic analysis must demonstrate that expected velocities in new distribution mains do not exceed five feet per second at the PHF.
460-30.04 Hazen Williams Coefficient.
The hydraulic analysis shall use roughness coefficients (C-factors) in the Hazen-Williams formula in accordance with the following:
Hf = 0.002083 x L x (100/C)1.85 x (Q1.85 / D4.8655)
Where: Hf = head loss in feet of water L = length of pipe in feet Q = flow rate of water in gallons per minute C = Hazen-Williams friction coefficient D = inside diameter of the pipe in inches
Table 460.1
| Pipe | C-Factor |
|---|---|
| Ductile iron pipe (16 inches in diameter and above) | 120 |
| Ductile iron pipe (Less than 16 inches in diameter) | 130 |
| PVC pipe (All sizes) | 140 |
| HDPE pipe (All sizes) | 140 |
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§ 460-40
Material Specifications
460-40.01 General Requirements.
A.The contractor shall furnish potable water piping systems in accordance with the material specifications in this section.
B.All references in these Paulding County Standards and Specifications to industry standards (including but not limited to ASTM, ANSI, AWWA, OSHA) shall be to the latest revision unless stated otherwise.
C.All materials shall be new.
D.These material specifications include a list of preferred acceptable manufacturers for the various water system components (See Appendix 4.0, Section 4-20). The contractor may choose freely from the preferred acceptable manufacturers list and material submittals for such items are not required. Only products and materials from the preferred acceptable manufacturer's lists herein may be used in the work.
E.All water mains shall be ductile iron pipe.
F.All service lines shall be copper tubing unless otherwise specified by the Water System for extenuating circumstances.
G.All materials must be made in the USA.
H.Any pipe, fittings and appurtenances used in the installation or repair of water mains or services shall be lead-free pipe.
I.Any item required but not specified herein, or any product or manufacturer other than those listed will be considered a alteration. Material submittals are required for such items. Substitutions will not be allowed without the prior written approval of the Paulding County Water System. Substitutions, if allowed, shall meet all criteria of the detailed specifications. The burden of proof for compliance of any proposed substitution rests with the Contractor/Developer/Owner. Paulding County Water System will be the sole judge as to the acceptance of a proposed substitution and such decisions will be final.
§ 460-50
Potable Water Mains
460-50.01 Ductile Iron Pipe.
A.Ductile iron pipe shall be manufactured in accordance with AWWA C151. All pipes shall be furnished in standard lengths of 18 to 20 feet. All pipes shall be a minimum Pressure Class 350, unless otherwise specified or shown on the approved construction Drawings. All pipes shall be pressure rated as shown in the following table:
Table 460.2
| Pipe Sizes (inches) | Pressure Class (psi) |
|---|---|
| 4-12 | 350 |
| 14-18 | 350 |
| 20 | 300 |
| 24 | 250 |
| 30-54 | 200 |
| 60-64 | 200 |
fittings. Push-on and mechanical joints shall conform to AWWA C111.
Provide and install the appropriate gaskets, nuts and bolts for mechanical joints. Nuts shall be steel with American Standard Regular hexagonal dimensions, all as specified in ANSI B 17.2.
2.The only acceptable restrained joint systems are identified in the table below. See list of preferred acceptable manufacturers. No field welding of restrained joint pipe will be allowed.
Table 460.3
| Pipe Sizes (inches) | ACIPCO | U.S. Pipe |
|---|---|---|
| 4-12 | Fast-Grip Flex Ring | Field Lok, TR Flex |
| 16-24 | Fast-Grip Flex Ring | Field Lok, TR Flex |
| 30-36 | Flex Ring | TR Flex |
| 42-48 | Lok-Ring | TR Flex |
| 54-64 | Lok-Ring | TR Flex |
shall be specifically designed for clear spans.
2.On ductile iron fittings, mechanical joint restraints shall be incorporated into the design of the follower gland.
3.Restraint devices shall consist of multiple gripping wedges incorporated into the follower gland and meeting the requirements of ANSI A21.10 (AWWA C110). Gland body, wedges and wedge actuating components shall be ductile iron in accordance with ASTM A536. Dimensions of the gland shall be such that it can be used with the standard mechanical joint bell and tee head bolts. Twist off nuts (same size as the tee head bolts) shall be used to ensure proper actuation of the restraining device. The mechanical joint restraint shall be designed to accommodate the full working pressure of the pipe with a minimum safety factor of 2.0.
4.Where called for on the plans, joints on ductile iron piping may be restrained by utilizing a joint restrained gasket which includes a stainless-steel locking segment vulcanized into the rubber gasket. The gasket shall be rated for operating pressures up to 250 psi in accordance with ANSI A21.11 (AWWA C111).
5.Where it is necessary to restrain existing PVC pipe bells adjacent to valves and fittings, a harness restraint device shall be used in lieu of thrust blocking. The restraint shall be manufactured of ductile iron in accordance with ASTM A536. A split ring shall be used behind the pipe bell with a serrated ring to grip the pipe. A sufficient number of steel tie rods/bolts shall be used to connect the bell ring and the gripping ring. The harness restraint device shall accommodate the full working pressure of the pipe with a minimum safety factor of 2.0.
6.The use of concrete thrust blocks as a method of joint restraint shall be limited to situations such as ties to or work associated with existing systems where exposing several joints of pipe is not feasible due to existing ground conditions.
7.Where tie rods are used as a method of restraint at mechanical joint fittings and valves, offset eyebolts shall be used to connect tie rods to the fitting.
Tie rods shall be steel, threaded as required and installed with a washer and nut (same material as the rod) on either side of the joint. The size and number of tie rods shall be in accordance with the Standard Detail G11.
8.Flanged joints shall meet the requirements of ANSI B16.1, Class 125
9.Provide the appropriate gaskets for mechanical and flange joints. Gaskets for flange joints shall be made of 1/8-inch thick, cloth reinforced rubber;
gaskets shall be full-face type.
Title 3: Chapter 460
10.Bolts and Nuts.
(a)Provide the necessary bolts for connections. All bolts and nuts shall be threaded in accordance with ANSI B1.1, Coarse Thread Series, Class 2A external and 2B internal fit. All bolts and nuts shall be made in the United States.
(b)Bolts and nuts for mechanical joints shall be Tee Head Bolts and nuts of high strength low-alloy steel in accordance with ASTM A 242 to the dimensions shown in AWWA C111/ANSI A21.11.
(c)Flanged joints shall be bolted with through stud or tap bolts of required size as directed. Bolt length and diameter shall conform to ANSI/AWWA C115 for Class 125 flanges shown in ANSI/ASME B16.1.
(d)Bolts for exposed service shall be zinc plated, cold pressed, steel machine bolts conforming to ASTM A 307, Grade B. Nuts for exposed service shall be zinc plated, heavy hex conforming to ASTM A 563. Zinc plating shall conform to ASTM B 633, Type II.
(e)Bolts for submerged service shall be stainless steel machine bolts conforming to ASTM A 193, Grade B8. Nuts shall be heavy hex, stainless-steel conforming to ASTM A 194, Grade 8.
G.Mechanical joint glands shall be ductile iron.
H.Welded Outlet: Welded outlets may be provided in lieu of tees or saddles on mains with a diameter greater than or equal to 24-inches. The pipe joint on the outlet pipe shall meet the joint requirements specified above. The minimum pipe wall thickness of the parent pipe and the outlet pipe shall be Pressure Class 350. The welded outlet shall be rated for 250 psi working pressure. Each welded outlet shall be hydrostatically tested at 500 psi. The welded outlet shall be fabricated by the manufacturer of the parent pipe. The maximum outlet diameters shall not exceed those listed in the Table 460.4.
Table 460.4
| Parent Pipe Diameter (inches) | Maximum Outlet Diameter (inches) |
|---|---|
| 24 | 16 |
| 30 | 20 |
| 36 | 24 |
| 42 | 30 |
| 48 | 30 |
| 54 | 30 |
| 60 | 30 |
| 64 | 30 |
approved construction Drawings and where soil conductivity is found at levels detrimental to DIP. Polyethylene film shall be in accordance with AWWA C105.
J.Thrust collars shall be welded-on ductile iron body type designed to withstand thrust due to 250 psi internal pressure on a dead end.
K.Approval of workmanship and installation will be on the basis of the Water System Engineering Technician's inspection, the manufacturer's written certification that the pipe was manufactured and tested in accordance with the applicable standards and a stamped letter from the Professional Design Engineer that the installation is approved to be in accordance with the design after Professional Design Engineer’s field inspection. See Section 460-110.04.
460-50.02 Copper Pipe.
A.Pipe shall be rolled copper tubing, ASTM B 88, Type K.
B.Where required, sweat to screw adapters shall be cast bronze ANSI B16.18, wrought solder joint ANSI B16.22. Unions shall be cast bronze or bronze with solder connections. Joints shall be made with 95/5 solder for Type K pipe
460-50.03 Glands and Fittings.
A.Retainer Glands.
1.MJ Field Lok Gaskets /Retainer glands shall be provided at all mechanical joints, including fittings, valves, hydrants and other locations as shown on the approved construction drawings.
2.Retainer glands shall be ductile iron and shall be manufactured in the United States. All retainer glands on the Project shall be the product of a single manufacturer. See Water System Preferred Acceptable Manufacturers List.
Table or figure — shown as printedverify at source ↗
3. Retainer glands shall be equivalent to the following type: 1100
MEGALUG® Series. See Water System Preferred Acceptable
Manufacturers List. Compact/lightweight retainer glands shall not beallowed. The minimum working pressure and minimum weight, excluding set screws and gasket material, shall be as listed in Table 460.5.
Table 460.5 Retainer Gland Specifications
Table or figure — shown as printedverify at source ↗
Retainer Minimum Minimum
Gland Size Working Weight
(inches) Pressure (pounds)(psi)
Table or figure — shown as printedverify at source ↗
4 350 6.0 6 350 11.8 8 250 16.0 12 250 24.8 16 200 50.0 20 200 72.5 24 150 85.0
4.Hydrant Tees: Hydrant tees shall be equal to ACIPCO A10180 or U.S. Pipe U-592.
5.Anchor Couplings: Lengths and sizes shall be as shown on the Standard Details. Anchor couplings shall be equal to ACIPCO A 10895 or U.S. Pipe U-591.
6.Hydrant Connector Pipe: The connector pipe shall be ductile iron meeting the requirements of AWWA C153; 24-inch offset design so that the hydrant can be adjusted to ensure placement at the proper grade; shall have an anchoring feature at both ends so that when used with M.J. split glands a restrained joint is provided; cement lined in accordance with AWWA C104.
7.Detection Tape: Detection tape shall be composed of a solid aluminum foil encased in a protective plastic jacket. Tapes shall be color coded in accordance with APWA color codes with the following legends: Water Systems, Safety Precaution Blue, “Caution Water Line Buried Below”.
Colors may be solid or striped. Tape shall be permanently printed with no surface printing allowed. Tape width shall be a minimum of two inches when buried less than 10-inches below the surface. Tape width shall be a minimum of three inches when buried greater than 10-inches and less than 20 inches.
Title 3: Chapter 460
460-50.04 Gate Valves (GV).
Gate Valves (GV) shall be used for water mains up to 36-inches in diameter and shall be made in the United States.
A.Gate valves shall be resilient-seated type conforming to the requirements of AWWA C509, latest edition or AWWA C515, latest edition.
B.Gate valves size three inches up to 12-inches shall be resilient seat wedge type and shall conform with the specifications of the American Water Works Association, Designation C509, latest edition rated for 250 psi minimum working pressure. Gate valves shall be equipped with "O" ring stem seals above and below stem thrust collar. Gate valves for use on mechanical joint ductile iron pipe and slip joint ductile iron pipe shall have manufacturer's standardized mechanical joint ends. Gate valve body and bonnet shall be ductile or cast iron and shall be fusion bonded, interior and exterior.
C.Valves less than three inches in diameter shall have threaded ends. Larger valves shall be mechanical joint unless shown otherwise on the approved construction Drawings. Gate valves two and a half inches in diameter and smaller shall be bronze, heavy duty, rising stem (two and a half inches and smaller only), rated for 200 psi WSP. Valves shall conform to Federal Specification WW-V-54, Class A, Type II.
D.All internal ferrous surfaces shall be coated with epoxy to a minimum thickness of four mils. The epoxy shall be non-toxic, impart no taste to the water and shall conform to AWWA C550, latest edition.
E.Water mains in which the valves are installed shall be tested as specified and the valve must remain water tight under this pressure in each direction.
F.Valves shall open counter clockwise (no exceptions will be allowed); shall be designed for vertical installation; and shall be the non rising stem type.
G.Valves shall be equipped with valve boxes. Provide extension stems where required to bring the operating nut to within 30 inches of ground surface and shall have a 24 inches x 24 inches x ten inches concrete collar poured in place.
Trowel level with ground surface.
H.All seals between valve parts, such as body and bonnet, bonnet and bonnet cover, shall be flat gaskets or O-rings.
I.Valve disks shall be made of cast or ductile iron having a vulcanized, synthetic rubber coating.
J.Ball valves shall be full port bronze, heavy-duty type, lead free. Valve ends shall be threaded. Valves shall have a minimum 200 psi working pressure.
Valves shall have stainless steel nut and handle. Valves shall be made in the U.S.A. See Water System Preferred Acceptable Manufacturers List.
460-50.05 Fire Hydrants (FH).
A.All fire hydrants shall conform to the requirements of AWWA C502 for 150 psi minimum working pressure. Hydrants shall be the compression type, closing with line pressure. The valve opening shall be 5-1/4-inches. See Water System Preferred Acceptable Manufacturers List
B.In the event of a traffic accident, the hydrant barrel shall break away from the standpipe at a point above grade and in a manner which will prevent damage to the barrel and stem, preclude opening of the valve, and permit rapid and inexpensive restoration without digging or cutting off the water.
C.The means for attaching the barrel to the standpipe shall permit facing the hydrant a minimum of 360 degrees in different directions allowed by the bolt pattern.
D.Hydrants shall be fully bronze mounted with all working parts of bronze. Valve seat ring shall be bronze and shall screw into a bronze retainer.
E.All working parts, including the seat ring shall be removable through the top without disturbing the barrel of the hydrant.
F.The operating nut shall match those on the standard details. The operating threads shall be totally enclosed in an operating chamber, separated from the hydrant barrel by a rubber O-ring stem seal and lubricated by a grease or an oil reservoir. A stop nut shall be positioned in the top operating mechanism of the hydrant so that the valve stem cannot contact the bottom of the shoe when the hydrant is fully open.
G.Hydrant shall be a non-freezing design and be provided with a simple, positive, and automatic drain which shall be fully closed whenever the main valve is opened.
H.Hose and pumper connections shall be breech-locked, pinned, or threaded and pinned to seal them into the hydrant barrel. Each hydrant shall have two 2-1/2-inch hose connections and one 4-1/2-inch pumper connection, all with National Standard threads and each equipped with cap and non-kinking chain.
I.Hydrants shall be furnished with a mechanical joint connection to the spigot of the six-inch hydrant lead.
J.Minimum depth of bury shall be four feet. Extension sections shall be furnished where necessary to bring hydrant to the proper elevation. Extensions shall be installed in accordance with manufacturer's recommendations. The centerline of the 2½ inch connections shall be a minimum of 18 inches above finished grade.
K.All outside surfaces of the barrel above grade shall be painted silver with Sherwin Williams KEM 400 or Koppers Glamortex 501.
L.See Detail W-1 for typical Fire Hydrant Assembly.
460-50.06 Valve Boxes (VB) and Extension Stems.
A.All valves shall be equipped with valve boxes. The valve boxes shall be cast or ductile iron two-piece screw type with drop covers. Valve boxes shall have a 5.25-inch inside diameter. Valve box covers shall weigh a minimum of 13 pounds. The valve boxes shall be adjustable to 6-inches up or down from the nominal required cover over the pipe. Valve boxes shall be of sufficient length that bottom flange of the lower belled portion of the box is below the valve operating nut. Ductile or cast-iron extensions shall be provided as necessary.
Covers shall have "WATER VALVE" or "WATER" cast into them. All valve boxes and valve box risers shall be manufactured in the United States.
B.All valves shall be furnished with extension stems if operating nut is greater than four feet deep, to bring the operating nut to within 24-inches of the top of the valve box. Connection to the valve shall be with a wrench nut coupling and a set screw to secure the coupling to the valve's operating nut. The coupling and square wrench nut shall be welded to the extension stem.
460-50.07 Valve Markers (VM).
Where street curbs are installed, the Developer/Owner shall provide a saw cut ½”
deep “V” notch on top of curb adjacent to water valve location is required.
460-50.08 Tapping Sleeves and Valves (TS&V).
A.Tapping sleeves for mains shall be ductile iron of the split-sleeve, mechanical joint type. Tapping sleeves shall be equal to Mueller H-615. Tapping valves shall be equal to Mueller Model H-687 sizes four inch - 10", H-667 sizes 12" -24". See Water System Preferred Acceptable Manufacturers List.
B.The Contractor shall be responsible for determining the outside diameter of the pipe to be connected to prior to ordering the sleeve. The tapping sleeve shall be rated for 250 psi.
C.Valves shall be gate valves furnished in accordance with the specifications in section 2.4.1.4, with flanged connection to the tapping sleeve and mechanical joint connection to the branch pipe. Valves shall be resilient seat gate valves sizes six inches - ten inches. The tapping sleeve shall be supplied by the valve manufacturer.
D.Taps are not allowed on existing PVC mains. See Table 460.6.
Table 460.6 Permissible Wet Tap/Hot Tap Sizes Existing Pipe Largest Tap Size (inches) Permitted1 6 not permitted 8 6-inch 10 8-inch 12 10-inch 14 12-inch 16 14-inch 20 16-inch 24 Cut-in 30 Cut-in 1Next smallest pipe size largest tap permitted
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§ 460-60
Water Service Lines and Appurtenances
460-60.01 Corporation Cocks and Curb Stops.
Corporation cocks and curb stops shall be ball type, shall be made of bronze conforming to ASTM B 61 or B 62, and shall be suitable for the working pressure of the system. Ends shall be suitable for compression joint. Threaded ends for inlet and outlet of corporation cocks shall conform to AWWA C400; coupling nut for connection to flared copper tubing shall conform to ANSI B16.26. See Water System Preferred Acceptable Manufacturers List.
460-60.02 Meter Boxes.
Meter boxes shall be cast iron painted black with a locking lid quad valve box or plastic. If the boxes are plastic, the material shall be high density polyethylene.
Meter boxes shall have nominal dimensions of 19.75 inches x 25.75 inches at bottom, 17.75 inches x 23.5 inches opening, and 12 inches tall. The Water System will install the meter for domestic use after property owner applies for it. See Standard Detail W-5.
§ 460-70
Backflow Prevention Devices
460-70.01 Double Detector Check Backflow Preventer Assembly.
A.Provide a double detector check (DDC) backflow preventer (BFP) assembly in a size to match that of the required fire line service piping. The DDC-BFP assembly shall be provided with an OS & Y gate valve near the inlet and outlet sides of the device.
B.The DDC device shall be provided with three brass ball valve test cocks fitted with brass or plastic threaded plugs. A fourth test cock shall be provided on the upstream side of the inlet shut-off valve.
C.The DDC device and shut-off valve bodies shall be cast iron, coated inside and outside with an NSF- approved, fused epoxy coating and assembled with bolts that are resistant to electrolysis. All DDC device interior/exterior components shall be of materials equal in corrosion resistance to bronze and/or stainless steel to resist electrolysis.
D.Check valves shall have replaceable seats, and be accessible by top-entry only for maintenance and repair. The detector bypass line on the DDC-BFP assembly shall be of 3/4-inch copper pipe and have a bronze detector meter and a 3/4-inch DCV-BFP complete with unions and shut-off valves.
E.The DDC-BFP assembly shall be classified or listed by the Underwriters Laboratories, Factory Mutual Insurance, and bear the ASSE seal (ASSE Standard 1049). The DDC-BFP assembly shall have approval of and conform to all current requirements of the University of Southern California, Foundation for Cross-Connection Control (USC-FCCC). The DDC-BFP assembly shall be individually factory tested, shipped and installed as a unit.
F.The DDC-BFP assembly shall not be buried in earth but installed below ground in a concrete vault, and as close as practical to the property line of the premises.
G.Under no condition will any connection be allowed on the system other than for firefighting or fire protection purposes.
H.All DDC-BFP assemblies shall be tested at the time of installation and at least annually thereafter. A copy of all test and maintenance reports must be submitted to the Paulding County Water System.
I.The assembly shall meet the requirements of USC Manual 8th Edition, ASSE No. 1015, AWWA C506, CSA B64.5, IAPMO PA31, FCCCFR of USC Manual
–Section 10 and UL Classified File No. EX3185.
J.The Shut-off valves for backflow preventers in sizes two inch and smaller shall be full-port ball-type, with threaded connections and bronze bodies with copper content not less than 80 percent. Shut-off valves for backflow preventers in sizes 2½ inches and larger shall be full port ball-type, or resilient-wedge gate-type, with flanged connections, and iron bodies with FDA-approved fusion bonded epoxy coating inside and out.
K.Double check backflow preventers shall be listed in the Water System Preferred Acceptable Manufacturers List.
460-70.02 Double Detector Check Valve Assembly.
A.Double detector check valve assemblies shall conform to the following standards: A.S.S.E. Standard No. 1015, AWWA Standard C 506; FCCCHR of USC Manual Section 10, U.L. Classified File No. EX 3185, and be listed under CSA B.64 Standard.
B.All assemblies shall be standardly equipped with epoxy coated UL/FM listed OS & Y resilient seat gate valves. Check valve bodies shall be epoxy-coated cast iron. The by-pass line unit shall consist of an approved double check backflow preventer and water meter that reads in gallons.
C.Double detector check assemblies shall be Watts 709DDC or approved equal.
460-70.03 Reduced Pressure Zone (RPZ) Assemblies.
A.The RPZ shall consist of an internal pressure differential relief valve located in a zone between two positive seating check modules with captured springs and silicone seat discs. Seats and seat discs shall be replaceable in both check modules and the relief valve. There shall be no threads or screws in the waterway exposed to line fluids. Service of all internal components shall be through a single access cover secured with stainless steel bolts. The assembly shall also include two resilient seated isolation valves, four resilient seated test cocks and an air gap drain fitting.
B.The assembly shall meet the requirements of USC Manual 8th Edition, ASSE Std. 1013, AWWA C511, IAPMO File No. 1563 and CSA B64.4. See Water System Preferred Acceptable Manufacturers List.
460-70.04 Water Meter and Service Lines.
A.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.
B.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.
§ 460-80
Miscellaneous Items
460-80.01 Detection Tape.
Detection tape shall be composed of a solid aluminum foil encased in a protective plastic jacket. The tape shall be safety blue in color, shall be at least two and a half inches wide and will bear the printed identification "CAUTION: BURIED WATER LINE BELOW".
460-80.02 Casing Pipe.
A.Steel casing pipe shall be manufactured from steel conforming to ASTM A 139, Grade B and be new and unused with a minimum yield strength of 35,000 psi.
See Standard Detail Sheet G-5 for thickness. It shall be fully coated on the exterior and interior with a coal tar epoxy coating. The casing pipe diameter shall be six to eight inches greater than the “bell” diameter of the carrier pipe.
B.Wherever steel casing is required on the approved construction drawings, the carrier pipe shall be ductile iron pipe with push-on joints, with the appropriate gaskets (See Table 460.4). Approved spacers shall be used to secure the pipe on grade during grouting operations as specified below in Section 460-80.03.
C.The materials for casings under state highways shall be in accordance with the Georgia Department of Transportation Standard Specifications for the Construction of Roads and Bridges, latest edition. It shall be the contractor's responsibility to determine the exact requirements of the Georgia Department of Transportation. If there is a conflict between these regulations and the Georgia Department of Transportation Specifications, the latter shall take precedent.
460-80.03 Casing Spacers.
A.Each casing spacer shall be a two-piece shell per carrier pipe and made from T-304 stainless steel of a minimum 14-gauge thickness. Each shell section shall be lined with a 0.090" thick, ribbed PVC extrusion with a retaining section that overlaps the edges of the shell and prevents slippage.
B.Bearing surfaces (runners) shall be ultra high molecular weight polyethylene to provide abrasion resistance and a low coefficient of friction. The runners shall be attached to support structures (risers) at appropriate positions to properly support the carrier pipe within the casing pipe. The runners shall be mechanically bolted to the riser.
C.Risers shall be made of T-304 stainless steel of a minimum 10 gauge. All risers shall be MIG welded to the shell. Bottom risers six inches and over in height shall be reinforced. All reinforcing plates shall be 10 gauge T-304 stainless steel and shall be MIG welded to mating parts. All nuts, bolts and washers shall be 304 stainless steel.
460-80.04 End Seals.
Casing end seals shall be pull-over type made from neoprene with T-304 stainless steel bands for securing to the carrier and casing pipe unless dictated otherwise by permitting with GDOT or railroad specifications. When permitting requires different specifications, the more stringent specifications shall apply.
460-80.05 Air Release Valves.
A.Construction and Design.
1.The air release and vacuum break valve shall be of the compact single chamber design with solid cylindrical HDPE control floats housed in a tubular stainless-steel body with epoxy powder coated cast iron or steel ends secured by means of stainless-steel tie rods.
2.The valve shall have an integral "anti-shock" orifice mechanism which shall operate automatically to limit transient pressure rise or shock induced by closure to two times valve rated working pressure.
3.The intake orifice area shall be equal to the nominal size of the valve.
4.Large orifice sealing shall be affected by the flat face of the control float seating against a nitrile rubber O-ring housed in a dovetail groove circumferentially surrounding the orifice.
5.Discharge of pressurized air shall be controlled by the seating and unseating of a small orifice nozzle on a natural rubber seal affixed into the control float. The nozzle shall have a flat seating land surrounding the orifice so that the damage to the rubber seal is prevented.
6.The valve construction shall be proportioned with regard to material strength characteristics, so that deformation, leaking or damage of any kind does not occur by submission to twice the designed working pressure.
7.The valve design shall incorporate an over pressure safety feature that will fail without an explosive effect, such as is normally the case when highly compressed air is released suddenly. The feature shall consist of replaceable components such as gaskets or seals.
8.Connection to the valve inlet shall be facilitated by a flanged end conforming to ANSI B16.1 Class 125. Flanged ends shall be supplied with the requisite number of stainless steel or mild steel screwed studs inserted for alignment to the specific standard.
9.Provide a ¼-inch NPT test/bleed cock.
10.An isolation valve between the main and the air valve shall be installed in accordance with the approved construction drawings.
B.Air Valves shall be listed in the Water System Preferred Manufacturers list.
460-80.06 Sampling Station.
A.A sampling station, if required, shall have the correct laying length to install in a meter box specified in the standard detail. Both inlet and outlet connections shall be standard ¾-inch meter threads. The station shall consist of a standard meter re-setter with the inlet leading up through the water system's residential meter, through the check valve, and then out the outlet. The sampling station apparatus shall consist of a ½-inch lockable shut-off valve leading to a valve riser, then the ⅜-inch male quick disconnect valve. The valve and riser shall be positioned directly in line with the meter setter to avoid turning of the whole sampling station when pushing and sampling rod down on the valve.
All of the parts referenced above shall be brass, with plastic PVC push-on cap protecting the quick disconnect valve when not in use. The cap shall be sealed watertight with an O-ring below the quick disconnect valve.
B.A portable sampling rod with a female inlet shall couple to the male quick coupling with a quarter- turn and start the water flow. This all brass rod shall have two outlets, one for flushing, the other for sampling.
C.The sampling station and portable sampling rod shall be as shown in standard detail W-16.
460-80.07 Precast Concrete Components.
Provide precast concrete products in accordance with the following:
A.Precast Concrete Sections.
1.Precast concrete sections shall meet the requirements of ASTM C 478 for round shaped and ASTM C 913 for rectangular shaped precast concrete products. The minimum compressive strength of the concrete in precast sections shall be 4,000 psi. The minimum wall thickness shall be one-twelfth of the inside diameter of the base, riser or the largest cone diameter.
2.Transition slabs which convert bases larger than four feet in diameter to four-foot diameter risers shall be designed by the precast concrete manufacturer to carry the live and dead loads exerted on the slab.
3.Seal joints between precast sections by means of rubber O-ring gaskets or flexible butyl rubber sealant. Butyl rubber sealants shall meet the requirements of AASHTO M-198. Sealant shall be pre-formed type with a minimum nominal diameter of one-inch.
4.Butyl rubber sealant shall be equal to Kent Seal No. 2 or Concrete Sealants CS 202.
B.Brick and Mortar. Brick shall be whole and hard-burned, conforming to ASTM C 32, Grade MS. Mortar shall be made of one part Portland cement and two parts clean sharp sand. Cement shall be Type 1 and shall conform to ASTM C 150. Sand shall meet ASTM C 144.
C.Iron Castings.
1.Cast iron manhole frames, covers and steps shall meet the requirements of ASTM A 48 for Class 30 gray iron and all applicable local standards. All castings shall be tough, close grained, smooth and free from blow holes, blisters, shrinkage, strains, cracks, cold shots and other imperfections. No casting will be accepted which weighs less than 95% of the design weight.
All castings shall be thoroughly cleaned in the shop and given two coats of approved bituminous paint before rusting begins.
2.Manhole frames and covers shall be listed in the Water System Preferred Acceptable Manufacturers List
3.All frames and covers shall have machined horizontal bearing surfaces.
4.Bolt-down covers shall be equipped with four ½-inch stainless steel bolts and a ⅛-inch red rubber or rubber O-ring gasket. Covers shall be rotatable and interchangeable. Bolt holes shall be bored through so that debris entering the bolt hole will fall into the manhole. Bolt holes shall have the full 360° circle within the cover's radius when bored through the cover.
D.Plastic Steps. Manhole steps of polypropylene, molded around a steel rod, equal to products of M.A. Industries may be used.
E.Hatch.
1.Hatch shall be single or double leaf type as shown on the standard details.
2.The frame shall be ¼-inch extruded aluminum alloy 6063-T6, with built-in neoprene cushion and with strap anchors bolted to the exterior. Door leaf shall be ¼-inch aluminum diamond plate, alloy 6061-T6, reinforced with aluminum stiffeners as required. Stainless steel hinges shall be bolted to the underside and pivot on torsion bars that counterbalance the door for easy operation. The door shall open to 90 degrees and lock automatically in that position. A vinyl grip handle shall be provided to release the cover for closing. The door shall be built to withstand a live load of 300 pounds Title 3: Chapter 460 per square foot, and shall be equipped with a snap lock and removable handle. Bituminous coating shall be applied to exterior of frame by the manufacturer. The door shall also be provided with a hasp in addition to the built-in locking mechanism.
3.The hatch shall be listed in the Water System Preferred Acceptable Manufacturers List.
F.Vents.
1.Where vent pipes are shown on the approved construction plans, vents shall be of one-piece, welded steel construction. Vent pipes shall equal air valve size, but no less than four-inches. The vent pipe shall be grouted into a precast hole in the vault. The discharge of the vent pipe shall be provided with a 3/16-inch PVC coated mesh screen.
2.Where vent pipes are not shown on the approved construction plans, the frame and cover or hatch shall have enough 1-inch holes to provide equivalent opening as in air valve with a minimum of two holes. The quantity for each valve size is as follows: two-inch, four holes; three-inch, nine holes; four-inch, 16 holes; six-inch, 36 holes; eight-inch, 64 holes.
460-80.08 Concrete.
A.Concrete shall have a compressive strength of not less than 3000 psi.
B.If using bag cement, not less than five and half bags of cement per cubic yard shall be used with a slump between three and five-inches.
C.Ready-mixed concrete shall be mixed and transported in accordance with ASTM C 94. Reinforcing steel shall conform to the requirements of ASTM A 615, Grade 60.
§ 460-90
Installation of Water Mains and Appurtenances
460-90.01 General Requirements.
The Owner/Developer shall install potable water piping systems in accordance with the specifications detailed below. All references to industry standards (including ASTM, ANSI, AWWA.) shall be to the latest revision unless stated otherwise.
460-90.02 Transportation and Handling.
A.Any materials dropped or dumped will be subject to rejection by the water system engineering technician. Pipe handled on skids shall not be rolled or skidded against the pipe on the ground.
B.Handling: Handle pipe, fittings, valves and accessories carefully to prevent shock or damage such as handling pipe by rolling on skids, forklift, or front end loader. Do not use material damaged in handling. Slings, hooks or pipe tongs shall be padded and used in such a manner as to prevent damage to the exterior coatings or internal lining of the pipe.
460-90.03 Storage and Protection.
A.Store all pipes which cannot be distributed along the route. Make arrangements for the use of suitable storage areas.
B.Stored materials shall be kept safe from damage. The interior of all pipes, fittings and other appurtenances shall be kept free from dirt or foreign matter at all times. Valves and hydrants shall be drained and stored in a manner that will protect them from damage by freezing.
C.Pipe shall not be stacked higher than the limits recommended by the manufacturer. The bottom tier shall be kept off the ground on timbers, rails or concrete. Pipe in tiers shall be alternated: bell, plain end; bell, plain end. At least two rows of timbers shall be placed between tiers and chocks, affixed to each other in order to prevent movement. The timbers shall be large enough to prevent contact between the pipe in adjacent tiers.
D.Stored mechanical and push-on joint gaskets shall be placed in a cool location out of direct sunlight. Gaskets shall not come in contact with petroleum products. Gaskets shall be used on a first-in, first-out basis.
E.Mechanical-joint bolts shall be handled and stored in such a manner that will ensure proper use with respect to types and sizes.
§ 460-100
Excavation and Backfill
460-100.01 General Excavation.
This section covers the excavation, trenching, and backfilling for all water mains.
A.Topsoil and grass shall be stripped a minimum of six-inches over the trench excavation site and stockpiled separately for replacement over the finished grading areas.
B.Trenches shall be excavated to the lines and grades shown on the approved construction Drawings with the centerlines of the trenches on the centerlines of the pipes and to the dimensions, which provide the proper support, and protection of the pipe and other structures and accessories.
C.The excavation of any off-site trench shall not advance more than 100 feet ahead of the completed pipe work.
D.The Water System Engineering Technician shall be notified immediately upon encountering site conditions at variance to those indicated and any active or inactive utility encountered not indicated on the standard details.
E.No work shall be done to correct or incorporate unforeseen conditions until written instructions are issued.
F.No trenches will be permitted to be left open overnight, on weekends, or on holidays.
G.Trench Width for Pipelines.
1.The sides of all trenches shall be vertical, as much as possible, to a minimum of one foot above the top of the pipe. The maximum trench width shall be equal to the sum of the outside diameter of the pipe plus two feet.
The minimum trench width shall be that which allows the proper consolidation of the haunching and initial backfill.
2.Excavate the top portion of the trench to any width within the construction easement or right-of-way, which will not cause unnecessary damage to adjoining structures, roadways, pavement, utilities, trees or private property. Where necessary to accomplish this, provide sheeting and shoring.
3.Where rock is encountered in trenches, excavate to remove boulders and stones to provide a minimum of 6-inches clearance between the rock and any part of the pipe or manhole.
4.Whenever the prescribed maximum trench width is exceeded, the contractor shall provide Class A bedding and haunching for the full trench width as actually cut. The excessive trench width may be due to unstable trench walls, inadequate or improperly placed bracing and sheeting which caused sloughing, accidental over-excavation, intentional over-excavation necessitated by the size of the contractor’s tamping and compaction equipment, intentional over-excavation due to the size of the contractor’s excavation equipment, or other reasons beyond the control of the Engineer or the County.
H.Depth.
1.The trenches shall be excavated to the required depth or elevation, on the approved construction Drawings which allow for the placement of the pipe and bedding to the dimensions shown.
2.No storm sewer pipe, sanitary sewer pipe, sanitary sewer lateral pipe or force main shall be installed crossing within 2 feet of clearance of a water main. Sewer mains/force mains and lateral pipes when having to cross water mains shall be designed to cross under the water mains.
3.Where rock is encountered in trenches for pipelines, excavate to the minimum depth shown on the approved construction drawings, which will provide a minimum clearance below the pipe barrel of at least eight- inches for pipe 21-inches in diameter and smaller and 12-inches for larger pipe and manholes. Remove boulders and stones to provide a minimum of six-inches of clearance between the rock and any part of the pipe, manhole or accessory.
4.Depth of cover over the pipe shall be a minimum of four feet.
I.Excavated Materials.
1.Excavated materials shall be placed adjacent to the work to be used for backfilling as required. Topsoil shall be carefully separated and lastly placed in its original location.
2.Excavated material shall be placed sufficiently back from the edge of the excavation to prevent caving of the trench wall, to permit safe access along the trench and not cause any drainage problems. Excavated material shall be placed so as not to damage existing landscape features or man-made improvements.
Title 3: Chapter 460
3.Perform all trench excavation and backfilling activities in accordance with the Occupational Safety and Health Act of 1970 (PL 91-596), as amended.
The Owner/Developer shall pay particular attention to the Safety and Health Regulations Part 1926, Subpart P "Excavation, Trenching & Shoring" as described in OSHA publication 2226.
J.Rock Excavation.
1.All rock encountered shall be removed to provide a minimum clearance below the pipe barrel of at least eight inches for pipe 21-inches in diameter and smaller and 12-inches for larger pipe and manholes, and the trench built back to the correct grade with suitable select material thoroughly tamped into place, unless specifically directed to place stabilization material.
2.Blasting permits for each development shall be required. Blasting shall be done with all the rules, regulations and precautions specified by the state fire marshal and the Paulding County Fire Marshal.
3.The Owner/Developer’s contractor shall notify County Fire Marshal prior to blasting operations.
4.All blasting operations and all handling, storage and use of blasting materials shall be in strict accordance with federal, state and local ordinances and regulations and shall be approved by the Paulding County Fire Marshal. Blasts shall be restricted to the extent that no appreciable shock will be transmitted to existing structures, pipe lines, sewers, cables or other public or private facilities. The Owner/Developer shall be wholly responsible for any and all personal injury or property damage resulting from blasting.
K.Density Tests.
1.All trenches 12 inches or wider, as measured at the top, that are within roadways, or roadway right of ways, parking areas, and areas to be paved shall be tested for conformance to specified compaction requirements:
(a)These trenches shall be backfilled and compacted to their full depth.
(b)Tests shall be made within each 400 square feet of trench areas for each one foot of lift above top of conduit. Tests taken in one foot lifts shall be staggered.
(c)Compaction shall not be less than that of the surrounding areas or 95 percent of the maximum dry density as determined by the Standard Proctor Test. the top 12 inches shall be compacted to a minimum of 98 percent of the maximum dry density.
(d)Backfill within the Georgia Department of Transportation right-of-way shall meet all requirements as stipulated in the "Utility Accommodation Policy and Standards", as published by the Georgia Department of Transportation.
2.All trenches 12 inches or wider, as measured at the top, that are not within roadways, or other areas to be paved shall be compacted to not less than Title 3: Chapter 460 that of surrounding areas or 90 percent of the maximum dry density.
L.Owner/Developer shall be responsible for performance of all excavation to be in conformance with the most recent OSHA standards.
460-100.02 Groundwater Control.
The Owner/Developer shall control the groundwater throughout excavation activities. Methods of dewatering shall be at the option and responsibility of the Owner/Developer to prevent settlement or displacement of surface facilities due to dewatering. Dewatering shall be performed in such a manner that removal of soil particles is minimized and discharges will be conveyed to a point where it will not create safety issues or damage to private property.
460-100.03 Backfilling and Compaction.
A.Initial Backfill.
1.Initial backfill shall be placed to anchor the pipe, protect the pipe from damage by subsequent backfill and ensure the uniform distribution of the loads over the top of the pipe.
2.Place initial backfill material carefully around the pipe in uniform layers to a depth of at least 12-inches above the pipe barrel. Layer depths shall be a maximum of six-inches for pipe 18-inches in diameter and smaller and a maximum of 12-inches for pipe larger than 18-inches in diameter. The remaining backfill shall be placed evenly compacting each layer thoroughly to the specified compaction. Water settling shall not be permitted. Any trenches where settlement occurs shall be reopened, refilled and compacted, with the surface restored to the specified grade and compaction, and leveled for grassing.
3.Backfill on both sides of the pipe simultaneously to prevent side pressures.
4.Compact each layer thoroughly with suitable hand tools or tamping equipment.
5.Initial backfill shall be compacted to a minimum 90 percent of the maximum dry density, unless shown or specified otherwise.
6.If materials excavated from the trench are not suitable for use as backfill materials, provide select backfill material conforming to the requirements of this Section for initial backfill.
7.Prior to backfilling at manholes, structures, and other accessories, all forms, trash and debris shall be removed. Backfill material shall be symmetrical on all sides in eight-inch maximum layers. Each layer shall be moistened and compacted with tamps.
8.Where pipes are in a fill section or are projecting into fill sections, ductile iron pipe shall be provided. Where material beneath the pipe is determined by the Water System to be unstable, then concrete foundation supports at each joint shall be provided. Where pipe is not structurally supported, unstable material shall be removed and trench stabilization provided. A pipe bed shall be constructed of No. 57 crushed stone and be compacted to at least 90 percent of the maximum dry density, unless otherwise specified.
9.Earth backfill shall be free of stone and boulders. Acceptable backfill material may be from excavation or borrowed.
10.No rock will be allowed in the backfill within a distance of six inches from the pipe or the ground surface, and rock larger than six inches in the greatest dimension will not be permitted in any part of the trench.
B.Final Backfill.
1.Backfill carefully to restore the ground surface to its original condition.
2.If materials excavated from the trench are not suitable for use as backfill materials, provide suitable backfill material.
3.After initial backfill material has been placed and compacted, backfill with final backfill material. Place backfill material in uniform layers, compacting each layer.
(a)In six-inch layers, if using light power tamping equipment, such as a “jumping jack”.
(b)In 12-inch layers, if using heavy tamping equipment, such as hammer with tamping feed.
(c)In 24-inch layers, if using a hydra hammer.
4.If trench settles, re-fill, compact and grade the surface to conform to the adjacent surfaces.
5.Final backfill shall be compacted to a minimum 90 percent of the maximum dry density, unless specified otherwise.
6.Compact backfill underlying pavement and sidewalks, and backfill under dirt and gravel roads to a minimum 95% of the maximum dry density. The top 12 inches shall be compacted to a minimum of 98% of the maximum dry density.
7.Backfill within the Georgia DOT right-of-way or roadways shall meet the requirements stipulated in the "Utility Accommodation Policy and Standards, latest edition", published by the Georgia Department of Transportation.
460-10.04 Subsurface Obstructions.
The Owner/Developer, as required by Georgia law, shall call the Utilities Protection Center (UPC) and those utilities, agencies or departments that own and/or operate utilities in the vicinity of the construction work site to verify the location of, and possible interference with, the existing utilities, arrange for necessary suspension of service and make arrangements to locate and avoid interference with said utilities. Where these or unforeseen underground utilities are encountered, the location and alignment of the new facilities may be changed to avoid interference, upon written approval from the Water System.
§ 460-110
Water Main Installation
460-110.01 Laying and Jointing Pipe and Accessories.
Lay all pipes and fittings to accurately conform to the lines and grades on the construction drawings approved by the Water System Engineering Manager.
A.Pipe Installation.
1.Proper implements, tools and facilities shall be provided for the safe performance of the work. All pipe, fittings, valves and hydrants shall be lowered carefully into the trench by means of slings, ropes or other suitable tools or equipment in such a manner as to prevent damage to water main materials and protective coatings and linings. Under no circumstances shall water main materials be dropped or dumped into a trench.
2.All pipes, fittings, valves, hydrants and other appurtenances shall be examined carefully for damage and other defects immediately before installation. Defective materials shall be marked and held for inspection by the Engineering Technician, who may prescribe corrective repairs or reject the materials.
3.All lumps, blisters and excess coating shall be removed from the socket and plain ends of each pipe, and the outside of the plain end and the inside of the bell shall be wiped clean and dry and free from dirt, sand, grit or any foreign materials before the pipe is laid. No pipe containing dirt shall be laid.
4.Foreign material shall be prevented from entering the pipe while it is being placed in the trench. No debris, tools, clothing or other materials shall be placed in the pipe at any time.
5.As each length of pipe is placed in the trench, the joint shall be assembled and the pipe brought to correct line and grade. The pipe shall be secured in place with approved backfill material in water main piping construction only.
6.It is not mandatory to lay pipe with the bells facing the direction in which work is progressing in water main piping construction only.
7.Applying pressure to the top of the pipe, such as with a backhoe bucket, to lower the pipe to the proper elevation or grade, shall not be permitted.
8.Provide locate tape for all water main only when repairing existing PVC.
B.Alignment and Gradient.
1.Lay pipe straight in alignment and gradient or follow true curves as nearly as practicable. Do not deflect any joint more than the maximum deflection recommended by the manufacturer.
2.Maintain a transit, level and accessories on the job to lay out angles and ensure that deflection allowances are not exceeded.
C.Expediting of Work.
D.Protection. Excavate, lay the pipe, and backfill as closely together as possible.
Do not leave unjointed pipe in the trench overnight. Backfill and compact the trench as soon as possible after laying and jointing is completed. Cover the exposed end of the installed pipe each day at the close of work and at all other times when work is not in progress. If necessary to backfill over the end of an uncompleted pipe or accessory, close the end with a suitable plug, either push-on, mechanical joint, restrained joint or as approved by the Engineering Technician.
E.Joint Assembly. Push-on, mechanical, flange and restrained type joints shall be assembled in accordance with the manufacturer's recommendations to ensure that it has been “homed” 100 percent.
F.Cutting Pipe. Cut ductile iron pipe using an abrasive wheel saw. Tie in using a suitable saw; remove all burrs and smooth the end before jointing. The pipe shall be cut the pipe and the end beveled, as necessary, to provide the correct length of pipe necessary for installing the fittings, valves, accessories and closure pieces in the correct location. Only push-on or mechanical joint pipe shall be cut.
G.Polyethylene Encasement. Installation shall be in accordance with AWWA C105 and the manufacturer's instructions. All ends shall be securely closed with tape and all damaged areas shall be completely repaired to the satisfaction of the Water System Engineering Technician.
H.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 Water System Engineering Technician. Valves shall be closed before being installed.
2.Valves, fittings, plugs and caps shall be set and joined to the pipe for cleaning, laying and joining 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 Water System Engineering Technician.
4.If valve boxes are installed concurrently with valves, the Owner/Developer shall be responsible for maintaining valve boxes until the warranty period expires. All lost or damaged valve boxes shall be replaced by the Title 3: Chapter 460 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 Water System. 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.A valve marker shall be provided for each underground valve…
8.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.
9.Non restrained and push-on joints shall not be installed within 15 feet of restrained joints at valves or fittings, unless shown otherwise on the approved construction drawings.
10.A saw cut ½” deep “V” notch on top of curb adjacent to water valve location/s is required for each underground valve.
I.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 Engineering Technician.
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.
3.Hydrants shall be set to the established grade, with the centerline of the lowest nozzle at least 12-inches above the ground or as directed by the Engineer.
4.Hydrants shall be attached to the water main by the following method:
(a)For mains 16-inches and smaller, the isolation valve shall be attached to the main by connecting the valve to the hydrant tee.
(b)The isolation valve shall be attached to the hydrant by providing an anchor coupling or hydrant connector pipe between the valve and hydrant, if the hydrant and valve are less than two feet apart. Otherwise, provide ductile iron pipe with retainer glands on the hydrant and valve.
5.When a hydrant is set in soil that is pervious, drainage shall be provided at the base of the hydrant by placing coarse gravel or crushed stone mixed with coarse sand from the bottom of the trench to at least six-inches above the drain port opening in the hydrant to a distance of 12-inches around the elbow (hydrant shoe).
6.When a hydrant is set in clay or other impervious soil, a drainage pit two Title 3: Chapter 460 feet by two feet by two feet shall be excavated below each hydrant and filled with coarse gravel or crushed stone mixed with coarse sand under and around the elbow (hydrant shoe) of the hydrant and to a level of six-inches above the drain port.
7.All hydrants shall be located as shown on the Drawings or as directed by the Engineer. Provide adequate resistance to avoid transmitting shock moment to the lower barrel and inlet connection. This shall be accomplished by pouring a concrete collar approximately six-inches thick with a diameter of 24-inches at or near the ground line around the hydrant barrel.
8.All hydrants that are not in service shall have a Paulding County approved marker.
J.Air Valve Vaults.
1.Construct the vault or manhole as detailed on the approved construction drawings.
2.The frame and cover or hatch shall be cast into the top slab. The floor door drain shall be piped to vault exterior.
3.Manholes shall be constructed such that their walls are plumb.
460-110.02 Connections to Water Mains.
A.Connection methods to existing water mains shall be on a case by case basis.
Utilizing a wet tap with TS&V may only be approved by the Director in hardship cases when a cut in tee would be extremely difficult.
B.Location. Before laying pipe, locate the points of connection to existing water mains and uncover as necessary for the Engineer to confirm the nature of the connection to be made.
C.Interruption of Services. Make connections to existing water mains only when system operations permit as directed by the Engineering Manager or designee.
Operate existing valves only with the specific authorization and direct supervision of the Water System Engineering Technician.
D.Tapping Sleeves.
1.Holes in the new pipe shall be machine cut, either in the field or at the factory. No torch cutting of holes shall be permitted.
2.Prior to attaching sleeve, the pipe shall be thoroughly cleaned as per procedures.
3.Before performing field machine cut, the water tightness of the sleeve assembly shall be pressure tested in accordance with manufacturer’s specifications. The interior of the assembly shall be filled with water. An air compressor shall be attached, which will induce a test pressure of 250 psi.
No leakage shall be permitted for a period of five minutes.
4.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.
E.Connections Using Solid Sleeves. Where connections are shown on the approved construction drawings using solid sleeves, the Owner/Developer shall furnish materials and labor necessary to make the connection to the existing pipe line.
F.Connections Using Couplings. Where connections are shown on the approved construction drawings using couplings, the Owner/Developer shall furnish materials and labor necessary to make the connection to the existing pipe line, including all necessary cutting, plugging and backfill.
G.Service Lines.
1.Copper tubing between tap and water meter shall be one continuous length of pipe with no intermediate joints or connections. The service line shall be placed without sharp turns or bends from the water main to the meter box.
2.When meters are located on the opposite side of the street from the water main, new copper service lines shall be extended through a common six-inch bore, Schedule 40 PVC conduit to the service side. Replacement of existing services may be by free bore without a casing.
3.Provide detection tape over all service lines.
4.One and a half inch and two-inch water services are saddle tapped to the water main using Brass material Certified to ANSI/NSF Standard 61.
460-110.03 Thrust Restraint.
A.Provide restraint at all points where hydraulic thrust may develop including but not limited to hydrant connections, tees, bends and fittings.
B.Retainer Glands: Provide retainer glands where shown on the approved construction drawings. Retainer glands shall be installed in accordance with the manufacturer's recommendations.
C.Harnessing.
1.Provide harness rods only where specifically shown on the Drawings or directed by the Engineer.
2.Harness rods shall be manufactured in accordance with ASTM A 36 and shall have an allowable tensile stress of no less than 22,000 psi. Harness rods shall be hot dip galvanized or field coated with bitumastic before backfilling.
3.Where possible, harness rods shall be installed through the mechanical joint bolt holes. Where it is not possible, provide 90° bend eye bolts.
4.Eye bolts shall be of the same diameter as specified in AWWA C111 for that pipe size. The eye shall be welded closed. Where eye bolts are used in conjunction with harness rods, an appropriate size washer shall be utilized with a nut on each end of the harness rod. Eye bolts shall be of the same material and coating as the harness rods.
C.Thrust Collars. Collars shall be constructed as shown on the drawings.
Concrete and reinforcing steel shall meet the requirements as specified in the standard details. The welded-on collar shall be designed to meet the minimum allowable load shown on the approved construction drawings. The welded-on collar shall be attached to the pipe by the pipe manufacturer.
D.Concrete Blocking.
1.Provide concrete blocking for all bends, tees, valves, and other points where thrust may develop, except where other exclusive means of thrust restraint are specifically shown on the approved construction drawings.
2.Concrete shall be as specified in Section 460-80.08 and on the standard details.
3.Form and pour concrete blocking at fittings as shown on the standard details and as directed by the Engineering Manager. Pour blocking against undisturbed earth. Increase dimensions when required by over excavation.
460-110.04 Inspection and Testing.
A.All sections of the water main subject to internal pressure shall be pressure tested in accordance with AWWA C600 and these Specifications. A section of main will be considered ready for testing after completion of all thrust restraint and backfilling.
B.Each segment of water main between main valves shall be tested individually.
C.Test Preparation.
1.For water mains less than 24-inches in diameter, flush sections thoroughly at flow velocities, greater than two-and a half feet per second, adequate to remove debris from pipe and valve seats. Partially open valves to allow the water to flush the valve seat.
2.Partially operate valves and hydrants to clean out seats.
3.Provide temporary blocking, bulkheads, flanges and plugs as necessary, to assure all new pipes, valves and appurtenances will be pressure tested.
4.Without a hydrant present, before applying test pressure, air shall be completely expelled from the pipeline and all appurtenances. Insert corporation cocks at highpoints to expel air as main is filled with water as necessary to supplement automatic air valves. Corporation stops shall be constructed as detailed on the approved construction drawings with a meter box.
5.Fill pipeline slowly with water. Provide a suitable pump with an accurate water meter to pump the line to the specified pressure.
6.The differential pressure across a valve or hydrant shall equal the maximum possible, but not exceed the rated working pressure. Where necessary, provide temporary backpressure to meet the differential pressure restrictions.
7.Valves shall not be operated in either the opening or closing direction at differential pressures above the rated pressure.
D.Test Pressure. Test the pipeline at 250 psi measured at the lowest point for at least two hours. Maintain the test pressure within five psi of the specified test pressure for the test duration. Should the pressure drop more than five psi at any time during the test period, the pressure shall be restored to the specified test pressure. Provide an accurate pressure gage with graduation not greater than five psi.
E.Leakage.
1.Leakage shall be defined as the sum of the quantity of water that must be pumped into the test section, to maintain pressure within five psi of the specified test pressure for the test duration plus water required to return line to test pressure at the end of the test. Leakage shall be the total cumulative amount measured on a water meter.
2.The County assumes no responsibility for leakage occurring through existing valves.
F.Test Results. No test section shall be accepted if the leakage exceeds the limits determined by the following formula:
L = SD (P)½ 133,200
Table or figure — shown as printedverify at source ↗
Where: L = allowable leakage, in gallons per hour
S = length of pipe tested, in feet
D = nominal diameter of the pipe, in inchesP = average test pressure during the leakage test, in pounds per square inch (gauge)
As determined under Section 4 of AWWA C600.
If the water main section being tested contains lengths of various pipe diameters, the allowable leakage shall be the sum of the computed leakage for each diameter. The leakage test shall be repeated until the test section is accepted. All visible leaks shall be repaired regardless of leakage test results.
G.Completion. After a pipeline section has been accepted, relieve test pressure.
Record type, size and location of all outlets on record drawings.
460-110.05 Disinfection of Pipeline.
A.After successfully pressure testing each pipeline section, disinfect in accordance with AWWA C651 for the continuous-feed method and these Specifications.
B.Disinfection shall be performed by the Owner/Developer. Before disinfection is performed, the Owner/Developer shall submit a written procedure for approval to the Engineering Technician before being permitted to proceed with the disinfection. This plan shall also include the steps to be taken for the neutralization of the chlorinated water. The process may performed by a specialty contractor.
C.Chlorination.
1.Apply chlorine solution to achieve a concentration of at least 25 milligrams per liter free chlorine in new line. Retain chlorinated water for 24 hours. All valves and hydrants shall be operated to ensure disinfection of the appurtenances. Water shall be supplied from a temporary source protected by appropriate backflow prevention devices. Backflow preventer must be approved by the Water System prior to connection. Chlorine shall be injected no more than ten feet from the beginning of the new main.
2.Chlorine concentration shall be recorded at every outlet along the line at the beginning and end of the 24-hour period.
3.After 24 hours, all samples of water shall contain at least 10 milligrams per liter free chlorine. Re-chlorinate if required results are not obtained on all samples.
4.After 24 hours, all samples of water shall contain at least 10 milligrams per liter free chlorine. Re-chlorinate if required results are not obtained on all samples.
D.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.
E.Bacteriological Testing: After final flushing and before the water main is placed in service, the Contractor shall collect samples from the line and have tested for bacteriological quality in accordance with the Georgia Rules for Safe Drinking Water, Chapter 391-3-5. One set of samples shall be collected from every 1,200 feet of water main, plus one set from each end of main and one set from each branch. Testing shall be performed by the Water System's water laboratory of record. Re-chlorinate lines until required results are obtained.
460-110.06 Disinfection When Cutting into Extension Water Mains.
Disinfection shall be performed by the Owner/Developer. Before disinfection is performed, the Owner/Developer shall submit a written procedure for approval to the Engineering Technician before being permitted to proceed with the disinfection.
A.Shall be performed when mains are wholly or partially dewatered;
B.Shall follow the current AWWA C651 Standards, including trench treatment, swabbing with hypochlorite solution, flushing and/or slug chlorination as appropriate;
C.Bacteriological testing shall be performed after the tie in is complete. However, depending upon the circumstances, the water main may be returned to service prior to completion of testing to minimize the time the customers are out of service.
460-110.07 Abandonment of Water Mains.
A.General: Abandon in place all existing water main segments indicated on the approved construction drawings to be abandoned. Perform abandonment after the new water main has been placed in service and all water main services have been changed over to the new main. Salvage for the Water System, existing fire hydrants, valve boxes, valve markers, and other materials indicated on the approved construction drawings or located on water mains abandoned.
B.Capping and Plugging: Disconnect by sawing or cutting and removing a segment of existing pipe where cutting and capping or plugging is shown on the approved construction drawings or directed by the Engineer Technician.
Provide a watertight pipe cap or plug and concrete blocking for restraint to seal off existing mains indicated to remain in service. Seal ends of existing mains to be abandoned with a pipe cap or plug or with a masonry plug and minimum six-inch cover of concrete on all sides around the end of the pipe. The Owner/Developer shall be responsible for uncovering and verifying the size and material of the existing main to be capped or plugged.
C.Salvaging Materials: Salvage existing fire hydrants, valve boxes, valve markers and other materials as indicated on the Drawings and deliver salvaged items in good condition to the Water System Maintenance Facility. Coordinate delivery and placement of salvaged materials in advance with the Water System Engineering Technician.
D.Pavement Removal and Replacement: Perform any necessary pavement removal and replacement in accordance with the PDOT or GDOT requirements and shown on the approved Drawings and Specifications.
460-110.08 Removing and Replacing Pavement
A.All paved roads will be bored and cased. A bore must be attempted before consideration will be given to cutting the street.
B.Existing roadways shall not be open cut unless a permit is granted by the Georgia D.O.T. and/or the Paulding County Department of Transportation.
Submittal of an authorization letter from the State D.O.T. or the County D.O.T.
is required. Salvaging Materials: Salvage existing fire hydrants, valve boxes, valve markers and other materials as indicated on the Drawings and deliver salvaged items in good condition to the Water System Maintenance Facility.
Coordinate delivery and placement of salvaged materials in advance with the Water System Engineering Technician.
C.One lane of traffic shall be maintained open at all times. Construction work shall be limited to time between 9 a.m. and 4 p.m.
D.The owner/developer shall furnish traffic control devices and certified personnel to direct traffic per permit.
E.The above requirements may be altered with the written approval of the PDOT in extenuating circumstances.
F.Remove existing pavement as necessary for installing the pipeline and appurtenances.
G.The owner/developer shall replace with like materials at his expense all pavements, walks, and driveways removed or damaged in connection with the work. Pavement repairs shall be smooth and unnoticeable and of the same elevation as the existing paving. In the removal of pavement, the owner/developer shall salvage all sound and undamaged materials and store them at a convenient location for reuse in pavement replacements. Any additional new rock concrete, asphalt or other replacement materials shall in all cases conform to the PDOT’s specifications.
H.Before removing any pavement, mark the pavement neatly paralleling pipelines and existing street lines. Space the marks the width of the trench in neat lines.
I.Saw cut asphalt pavement along the marks using a rotary saw or other suitable tool. Break concrete pavement along the marks by scoring with a rotary saw and breaking below the score by the use of jackhammers or other suitable tools.
J.Do not pull pavement with machines until completely broken and separated from pavement to remain.
K.Do not disturb or damage the adjacent pavement. If the adjacent pavement is disturbed or damaged, remove and replace the damaged pavement.
L.Remove and replace sidewalks disturbed by construction for their full width and to the nearest undisturbed joint.
M.Remove and replace or tunnel under any curb disturbed by construction to the nearest undisturbed joint.
N.Upon completion of backfilling and consolidation of the backfill, arrange to have the compaction tested by an independent testing laboratory approved by PDOT. After compaction testing has been satisfactorily completed, replace all pavements, sidewalks and curbs removed. Gravel roads and drives shall meet the requirements for graded aggregate sub-base.
O.Pavement restoration shall meet the requirements of GDOT or PDOT.
P.On 3rd party property, restoration of offsite pavement must be to the same or better condition and with PDOT approval.
Q.Complete pavement restoration as soon as possible after backfilling.
R.Prior to replacing pavement, make a final cut in the pavement 12-inches back from the edge of the previous cut line. Make the cut using a rotary saw.
Remove pavement and base material to a depth of 10-inches below finished grade. Construct an eight-inch thick concrete (3000 psi) bridge the full width of the pavement cut (i.e... trench width plus 24-inches). Apply tack coat and two-inches of Type F asphalt when concrete has cured. See utility cut detail.
S.Replace all street roadway pavement, driveways, sidewalks, and curbs with the same material and to the same dimensions as existing.
T.Should any pavement restoration or repairs fail or settle during the life of the Contract, including the bonded period, promptly restore or repair defects.
U.Concrete pavement removal and replacement shall conform to the applicable sections of the Georgia Department of Transportation Standard Specifications Title 3: Chapter 460 for the Construction of Roads and Bridges, latest edition or PDOT standards as applicable.
460-110.09 Railroad Crossings
Railroad crossings shall be made in accordance with all requirements of the affected railroad. It will be the owner/developer’s responsibility to obtain all requirements from the railroads and furnish all labor and materials required to fulfill such requirements. The owner/developer shall furnish and install the casing under the tracks with whatever material and with whatever methods and under whatever regulations are required by the railroads.
460-110.10 Field pressure testing
A.After the pipe has been installed, the complete pipeline shall be subjected to a hydrostatic pressure test.
B.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:
1.At all high points, where air release valves or blow-off assemblies 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.
2.A test pump shall be installed at the low point of the section being tested and the pipe shall be slowly filled with water.
3.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.
4.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.
5.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.
6.The owner/developer shall, at his own expense, locate and make repairs as necessary until the leakage is within the specified allowance.
7.All visible leaks shall be repaired regardless of the amount of leakage.
8.The owner/developer 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 Water System.