Section 3510: Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011

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1 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 PART 1 - GENERAL 1.01 SCOPE OF WORK A. These specifications cover the pipes, fittings, and appurtenances used for reclaimed water distribution systems. B. The CONTRACTOR shall replace, at his expense, all materials found to be defective or damaged in handling or storage. The CONTRACTOR shall, if requested by UTILITIES, furnish certificates, affidavits of compliance, test reports, or samples for analysis for any of the materials specified herein. All pipe delivered to project site for installation is subject to random testing for compliance with the designated specifications. C. Pipe and fitting interior linings shall conform to ANSI/NSF 61 list of approved materials standard. PART 2 - PRODUCTS 2.01 PIPE MATERIALS A. PVC Pipe: PVC reclaimed water distribution mains shall be manufactured in accordance with AWWA standard C900 or C909, latest edition. Pipe shall have a minimum pressure rating of 150 psi and have a maximum dimension ratio of 18. Pipe shall be pantone purple 522-C in color. B. Ductile Iron Pipe: Ductile iron pipe shall conform to ANSI/AWWA A21.51/C151. Pipe shall be pressure class of 350 for pipe 4 to 12 inches in diameter. Pipes 16 to 24 inches in diameter shall be pressure class 250. Pipes 30 to 64 inches in diameter shall be pressure class 200. Pipe shall be color coded pantone purple 522-C with tape. The tape (min 2 ) shall be permanently affixed to the top and each side of the pipe (three locations parallel to the axis of the pipe). For pipes less than 24 inches in diameter, a single tape may be used along the top of the pipe. C. HDPE Pipe: HDPE pipe shall be in accordance with AWWA C906 and shall have an outside diameter equal to ductile iron pipe for the same size. Pipe shall have a minimum dimension ratio of 11 for use with ductile iron pipe fittings and have a working pressure of 150 psi. Pipe shall be color coded pantone purple 522-C JOINT MATERIALS A. PVC Pipe Joints: PVC pipe shall have integral bell push on type joints conforming to ASTM D3139. B. Ductile Iron Pipe Joints: 1 of 9

2 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 Joints for ductile iron pipe shall be push-on or mechanical joints conforming to ANSI/AWWA A21.11/C111. Where called for in the PLANS, restrained or flanged joints shall be provided. Flanged points shall conform to ANSI Standard B pounds. C. HDPE Pipe Joints: HDPE joints shall conform to AWWA C FITTINGS A. PVC Pipe Fittings: Fittings used with PVC pipe shall be ductile iron pipe fittings in accordance with Section 3114 Installation of Pipe.. B. Ductile Iron Pipe Fittings: C. All fittings shall be in accordance with Section 3114 Installation of Pipe. HDPE Pipe Fittings: 1. HDPE mechanical joint adapter shall be joined to the HDPE pipe by butt fusion. HDPE mechanical joint adapter shall be molded or fabricated conforming to AWWA C906. Molded fittings shall conform to ASTM D2683 for socket-type fittings, ASTM D3261 for butt-type fittings, or ASTM F1055 for electro fusiontype fittings. 2. On a case by case basis as approved by the COUNTY, mechanical bolt-on fittings may be used as an alternative to butt fusion adapters. Stainless steel pipe stiffeners shall be installed for internal circumferential support of the pipe ends when mechanical bolt-on fittings are used COATINGS AND LININGS FOR DUCTILE IRON PIPE AND FITTINGS A. Fittings Ductile iron fittings shall have fusion-bonded epoxy coating in accordance with ANSI/AWWA C116 or cement-mortar with a seal coat in accordance with ANSI/AWWA A21.4/C104. Fusion-bonded epoxy shall be holiday free and tested in accordance with ASTM G62 method A or method B. Testing method at the discretion of the applicator. Any holidays indicated by the detector shall be repaired in accordance with the manufacturer s repair procedures. B. Pipe Ductile iron pipe will have an interior protective lining of cement-mortar with a seal coat of asphaltic material in accordance with ANSI/AWWA A21.4/C104. Exterior ductile iron pipe shall be coated with asphaltic material in accordance with a minimum one mil thick in accordance with ANSI/AWWA A21.51/C151 for below ground piping only. C. Additional Applied Exterior Coatings for Above Ground Pipe and Fittings 2 of 9

3 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 Pipe, fittings and valves for above ground applications shall be accordance with the Section 3117 Coatings and Linings. Primer and field coats shall be compatible and shall be applied in accordance with the manufacturers recommendations. Refer to Appendix D, List of Approved Products. Final field coat shall be pantone purple 522-C for reclaimed water pipe, valves and appurtenances. Asphaltic seal coat applied to the exterior of above ground piping / fittings shall be blasted and completely removed prior to coating per Section 3117 Coatings and Linings POLYETHYLENE ENCASEMENT 1. Polyethylene encasement shall be in accordance with ANSI/AWWA A21.51/C105, wrapping colors to be pantone purple 522-C. Polyethylene encasements are required in accordance with C105 and when crossing, or adjacent to, power easements, gas easements, any location where induced currents may be present and in areas where aggressive soils exist SERVICE PIPE, STOPS, FITTINGS, AND SERVICE SADDLES A. Service Connections at Main: 1. One-inch service connections shall be brass body reduced port type corporation stops, equipped with connections compatible with the polyethylene tubing and threaded in accordance with specifications in AWWA C800, AWWA C901, and shall comply with NSF Service connections, 2-inch through 12-inch, shall be iron body resilient seat gate valves. Two-inch services at the reclaimed water main shall have connections for female iron pipe by female iron pipe thread, conforming to AWWA C Service taps for air release valve installations shall utilize a 2-inch brass ball type corporation stop. B. Service Pipe: 1. One-inch and two-inch service lines shall be pantone purple 522-C polyethylene tubing, conforming to specifications in AWWA C800, SDR 9 and AWWA C Services 4-inch and larger shall be DIP from the point of connection to the existing main to the meter assembly, if the existing main is on the same side of the street as the property. If the existing main is on the opposite side of the street, as a minimum, the segment of the pipe immediately upstream from the meter assembly shall be DIP. C. Service Control Valves: 1. One-inch and two-inch size service control valves shall be reduced port ball valves, made of brass, cast and machined in accordance with specifications in AWWA C800, AWWA C901, compliant with NSF-61 and compatible polyethylene tubing connections. 3 of 9

4 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, For metered connections four-inch and greater, UTILITIES shall provide the valves with the meter. 3. For non-metered connections four-inch and greater, the CONTRACTOR shall provide resilient seat OS&Y gate valves. D. Service Fittings: 1. One-inch and two-inch fittings shall be brass, cast and machined in accordance with specifications in AWWA C800, AWWA C901, compliant with NSF-61 with compatible polyethylene tubing connections. 2. Fittings, 4, 6, 8 and 12 inches in size shall be the same as reclaimed water main fittings, as per this Section. E. Service Tapping Saddles: 1. Stainless Steel Service Saddles: Epoxy or nylon coated ductile iron body with stainless steel, 18-8 type 304 straps, AWWA tapered threads for 1-inch, and, two-inches to be iron pipe threads. Controlled OD saddles to be used on C905 PVC pipe, double straps to be 2-inch minimum width each, single strap to be minimum of three inches wide. 2. Service Connections: a. PVC Pipe Service Saddle: i. One-inch and two-inch services utilize brass body saddle with controlled OD for 12-inches and smaller pipe. ii. One-inch and two-inch taps on existing pipes larger than 12-inches shall use controlled OD epoxy or nylon coated ductile iron body with stainless steel 18-8 type 304 straps. iii. Four-inch or larger services shall be mechanical tapping sleeves. b. Ductile Iron Pipe Service Saddle: i. One-inch services shall be direct tapped. ii. Two-inch services shall use a controlled OD service tapping saddle with stainless steel straps and a ductile iron body that is either nylon or epoxy coated. iii. Four-inch or larger services shall be mechanical tapping sleeves. c. Concrete Pressure Pipe Service Saddle: i. Tapped concrete pressure pipe shall be in accordance with AWWA M-9, using a strap-type saddle made specifically for concrete cylinder pressure pipe. d. HDPE Pipe Service Saddle: i. One-inch and two-inch shall utilize controlled O.D. tapping saddle with epoxy or nylon coated. stainless steel 18-8-type 304 double straps, Taps to HDPE pipe shall be approved on a case by case basis.. 4 of 9

5 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 ii. Taps, 4-inch and larger, shall use wide body tapping sleeves with a broad cross section gasket set in a retaining groove that increases sealing capability as pressure increases. e. Steel Pipe Service Saddle: Welded-on steel sleeves shall be used for all sizes and applications RESILIENT SEAT GATE VALVES A. Gate valves shall be resilient seat gate valves, manufactured to meet or exceed the requirements of AWWA C509/C515, latest revision, and in accordance with these. Valves shall have an unobstructed waterway equal to or greater than the full nominal diameter of the valve. Valves shall have a minimum pressure rating of 250 psi. B. Gate valves shall be installed vertically per the design drawings and with minimum depth of cover per Table Vertical valves 16" and larger shall be AWWA C515 resilient seated only (16" and 24" no gearing required) above 24" shall be installed vertically with a spur gear actuator unless noted by the engineer. The valve body, bonnet, and bonnet cover shall be ductile iron ASTM A536. All ferrous surfaces inside and outside shall have a fusion-bonded epoxy coating in accordance with AWWA C 550. A two-inch wrench nut shall be provided for operating the valve. All valves are to be tested in strict accordance with AWWA C515. C. Directional Opening: All valves shall open left or counter clockwise. D. The valves shall be non-rising stems with the stem made of cast, forged, or rolled bronze as specified in AWWA C509. Two stem seals shall be provided and shall be of the O- ring type. The stem nut must be independent of the gate. E. The resilient sealing mechanism shall provide zero leakage at test and normal working pressure when installed with the line flow from either direction. F. Tapping Valves with Alignment Lip shall be placed vertical where possible for Water & Reclaimed Water. Tapping Valves 16" and larger AWWA C515 resilient seated only (16" and 24" no gearing required) above 24" shall be installed vertically with a spur gear actuator unless noted by the engineer. When tapping existing mains, valves 24" and above shall be furnished with NPT pipe plugs for flushing the tracks BUTTERFLY VALVES A. Valves 42 inches and larger may be butterfly valves, as approved by UTILITIES. Butterfly valves and operators shall conform to the AWWA Standard Specifications for Rubber Seated Butterfly Valves, Designation C504, latest version, except as hereinafter specified, shall be Class 150. B. The valve body materials shall be epoxy coated inside and out as per AWWA C550. The valve body shall be constructed of close grain cast iron per ASTM A126, Class B 5 of 9

6 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 or equivalent material. All retaining segments and adjusting devices shall be of corrosion resistant material. Valves shall have the manufacturer's name and valve rating cast in body. C. Valve seats shall be EPDM. Valve seats shall be field adjustable and replaceable without dismounting operator disc or shaft and without removing the valve from the line. All retaining segments and adjusting devices shall be of corrosion resistant material. Valve seats shall be designed to be leak-tight in both directions at differential pressures up to, and including, the rated pressure of the valve class. D. Valve disc shall be designed to withstand full differential pressures across the closed valve disc without exceeding a stress level equivalent to one fifth of the tensile strength of the material. E. The face-to-face dimensions of valves shall be in accordance with above-mentioned AWWA specification for short-body valve. F. The valve shaft shall be turned, ground, and polished constructed of 18-8 stainless steel and designed for both torsional and shearing stresses when the valve is operated under its greatest dynamic or seating torque. Shaft shall be of either a one-piece unit extending full size through the value disc and valve bearing or it may be of a stub shaft design. G. Valve Actuator: Actuators shall be designed for input torques based on 150 psi valve pressure and 16 ft/s velocity with a maximum input of 80 ft-lb on 2 nuts and shall withstand 250 ft-lbs. In general, the butterfly valve actuators shall conform to the requirements of AWWA standard specifications for Rubber Seated Butterfly Valves, Designation C504, insofar as applicable. All valve and actuators, shall be installed, adjusted, and tested as an assembly by the valve manufacturer at the manufacturing plant. An affidavit of compliance signed by the actuator manufacturer shall be required stating the provisions of ANSI/AWWA C504 have been met. The rated torque capability of each actuator shall be sufficient to seat, unseat, and rigidly hold, in any intermediate position, the valve disc it controls. H. Directional opening and Extension Stem: All valves shall open left or counter clockwise and a ground level position indicator and extension stem / shaft for the 2 nut shall be provided for buried valves VALVE BOXES A. Standard Two-Piece Cast Iron Valve Box: Cast-iron two-piece valve boxes are required for mains less than six feet below finished grade and less than or equal to 12 inches in diameter. Valve boxes shall be provided with suitable heavy bonnets and shall extend to such elevation at or slightly above the finished grade surface as directed by UTILITIES. The barrel shall be screw type only, having 5-1/4-inch shaft. The upper section shall have a flange at the bottom having sufficient bearing area to prevent settling and shall be complete with locking cast iron 6 of 9

7 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 covers. Covers shall have RECLAIMED WATER cast into the top for all reclaimed water mains. B. Valve Box Assembly: Valve box assemblies are required for any size main that is six feet or greater below finished grade or if mains are greater than 12 inches in diameter. Valve boxes shall be one complete assembled unit composed of the valve box and extension stem that attaches and locks to the two-inch wrench nut. All moving parts of the extension stem shall be enclosed in a housing to prevent contact with the soil. A valve box centering device designed to eliminate the shifting of the valve box against the operating nut of the valve shall be used. Valve box assembly shall be adjustable to accommodate variable trench depths six feet and greater as shown in the STANDARD DRAWINGS. C. Valve box insert shall be one complete assembled unit with a self-adjusting extension stem system that fits inside a standard valve box that will accommodate variable trench depths six-feet and greater as shown in the STANDARD DRAWINGS. D. Valve boxes shall have locking lids utilizing a five sided nut with a special wrench needed to open. Valve lids to be made as shown in the STANDARD DRAWINGS. E. Valve collars shall be 24 X 24 round or square and poured in place with 3000psi concrete or made out of a fiberglass re-enforced concrete polymer material manufactured to the specifications as shown in the STANDARD DRAWINGS F. Locating wire shall be 10-gauge single strand solid core copper wire with insulation. The color of the insulation shall be the same color as the color code for the pipe being installed. G. Valve markers are to be made of schedule 80 PVC and have a decal applied containing information as shown in the STANDARD DRAWINGS. The marker must be the same color as the pipe being marked AIR RELEASE VALVES A. The air release valves for use in reclaimed water mains shall be single body combination air release valves designed to release large quantities of air at start up, admit air on shut down and release air in operation. Air release valves shall be 316 stainless steel,, 316 stainless steel float, bronze water diffuser Buna-N or Viton seat and stainless steel trim. Air release valves must be in stalled in an enclosure as shown on the STANDARD DRAWINGS. Fittings from the main to the air release valve in the enclosure shall be threaded and made of brass. PART 3 - EXECUTION 3.01 MATERIAL IDENTIFICATION AND TESTING A. Pipe Identification: 1. Each length of pipe shall bear the name or trademark of the manufacturer, the location of the manufacturing plant, and the class or strength classification of the 7 of 9

8 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, 2011 pipe. The markings shall be plainly visible on the pipe barrel. Pipe, which is not clearly marked, is subject to rejection. The CONTRACTOR shall remove all rejected pipe from the project site within five working days. 2. All pipe not factory color-coded shall have a field applied, three inch wide pantone purple 522c stripe down the length of the pipe. B. Material Testing Requirements: 1. If requested by UTILITIES, a sample of pipe to be tested shall be selected at random by UTILITIES or the testing laboratory hired by UTILITIES. 2. When the samples tested conform to applicable standards, all pipe represented by such samples shall be considered acceptable based on the test parameters measured. Copies of test reports shall be available before the pipe is installed on the project. 3. In the event that any of the test samples fail to meet the applicable standards, all pipe represented by such tests shall be subjected to rejection. The CONTRACTOR may furnish two additional test samples from the same shipment or delivery, for each sample that failed and the pipe will be considered acceptable if all of these additional samples meet the requirements of the applicable standards. All such retesting shall be at the CONTRACTOR s expense. 4. Pipe, which has been rejected by UTILITIES, shall be removed from the site of the work by the CONTRACTOR and replaced with pipe that meets these specifications SEPARATION OF RECLAIMED WATER MAINS AND SEWERS Separation shall be in accordance with Standard Drawings listed in Appendix A INSTALLATION OF VALVES A. All valves shall be inspected upon delivery in the field to insure proper working order before installation. They shall be set and jointed to the pipe in the manner as set forth in the AWWA Standards for the type of connection ends furnished. All valves and appurtenances shall be installed true to alignment and rigidly supported. Any damage to the above items shall be repaired to the satisfaction of UTILITIES before they are installed NOTIFICATION AND CONNECTION TO EXISTING RECLAIMED WATER MAINS A. UTILITIES Construction and Water Reclamation Divisions shall be notified at least three days in advance to schedule main connections and valve operations. The water, wastewater, and reclaimed water valves are to be operated only by the COUNTY. All valves installed are to remain closed during construction. B. The CONTRACTOR shall exercise extreme caution when excavating in proximity of wastewater force mains. Force main and sewer locations shown on plans are not exact or guaranteed. The CONTRACTOR is responsible for field verifying existing utility locations. UTILITIES dispatch operator shall be notified immediately in the event of a force main, water main, or reclaimed water main break or damage at 8 of 9

9 STANDARDS AND CONSTRUCTION MANUAL : Reclaimed water Pipes, Valves, and Appurtenances February 11, The CONTRACTOR shall immediately repair all damage to UTILITIES mains, at the CONTRACTOR s expense. If the repair is not made in a timely manner, as determined by UTILITIES Inspector, UTILITIES may perform repairs and the CONTRACTOR will be charged for repairs RECLAIMED WATER SERVICE A. Reclaimed water service piping and connection shall be installed as indicated in the STANDARD DRAWINGS. The location of all service lines shall be as shown on the STANDARD DRAWINGS. On curbed streets the exact location for etching or cutting a R in the concrete curb shall mark each installed service. Where no curb exists, locations shall be adequately marked by a method approved by UTILITIES. 9 of 9