36C26118B0266-026.pdf

DEPARTMENT OF VETERANS AFFAIRS Project No.: 640-18-146

PALO ALTO HEALTH CARE SYSTEM

MPD – REPAIR ROADWAY / UNDERGROUND UTILITIES

FINAL

2015-08-11 SANITARY SEWER UTILITIES

33 30 00-1

SECTION 33 30 00

SANITARY SEWER UTILITIES

PART 1 - GENERAL

1.1 DESCRIPTION:

A. Outside, underground sanitary sewer system, complete, ready for operation, including all gravity flow lines, pressure (force) lines, manholes, cleanouts, frames, covers, structures, appurtenances, and connections to new building and structure, service lines, existing sanitary sewer lines, and existing sanitary structures, and all other incidentals.

1.2 RELATED WORK:

A. Maintenance of Existing Utilities: Section 01 00 00, GENERAL

REQUIREMENTS.

B. Excavation, Trench Widths, Pipe Bedding, Backfill, Shoring, Sheeting, Bracing: Section 31 20 00, EARTHWORK.

C. Concrete Work Reinforcing, Placement and Finishing; Section 03 30 00, CAST-IN-PLACE CONCRETE.

1.3 QUALITY ASSURANCE:

A. Products Criteria:

1. Multiple Units: When two or more units of the same type or class of materials or equipment are required, these units shall be products of one manufacturer.

2. Nameplates: Nameplate bearing manufacturer's name, or identifiable trademark, including model number, securely affixed in a conspicuous place on equipment, or name or trademark, including model number cast integrally with equipment, stamped, or otherwise permanently marked on each item of equipment.

B. Comply with the rules and regulations of the Public Utility having jurisdiction over the connection to Public Sanitary Sewer lines and the extension, and/or modifications to Public Utility Systems.

1.4 SUBMITTALS:

A. Submit in accordance with Section 01 33 23, SHOP DRAWINGS, PRODUCT

DATA, AND SAMPLES.

B. Manufacturers' Literature and Data: Submit the following as one package:

1. Pipe, Fittings, and, Appurtenances.

33 30 00-2

2. Jointing Material.

3. Manhole and Structure Material.

4. Frames and Covers.

5. Steps and Ladders.

6. Gate Valves.

7. Valve Boxes.

8. Check Valves.

1.5 APPLICABLE PUBLICATIONS:

A. The publications listed below form a part of this specification to the extent referenced. The publications are referenced in the text by the basic designation only.

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

A48/A48M-03.............Gray Iron Castings

A536-84(2004)...........Ductile Iron Castings

A615/A615M-06...........Deformed and Plain Carbon-Steel Bars for

Concrete Reinforcement

A625/A625M-03...........Tin Mill Products, Black Plate, Single Reduced

A746-03.................Ductile Iron Gravity Sewer Pipe

C12-06..................Installing Vitrified Clay Pipe Lines

C76-05b/C76M-05b........Reinforced Concrete Culvert, Storm Drain and

Sewer Pipe

C150-05.................Portland Cement

C425-04.................Compression Joints for Vitrified Clay Pipe and

Fittings

C478-06a/C478M-06a......Precast Reinforced Concrete Manhole Sections

C700-05.................Vitrified Clay Pipe, Extra Strength, Standard

Strength, and Perforated

C828-03.................Low-Pressure Air Test of Vitrified Clay Pipe

Lines

C857-95(2001)...........Minimum Structural Design Loading for

Underground Precast Concrete Utility Structures

33 30 00-3

D698-00ae1..............Laboratory Compaction Characteristics of Soil

Using Standard Effort (12,400 ft-lbf/ft3 (600 kN-m/m3))

D2321-05................Underground Installation of Thermoplastic Pipes for Sewers and Other Gravity-Flow Applications

D2412-02................Determination of External Loading

Characteristics of Plastic Pipe by Parallel-

Plate Loading

D2992-01................Practice for Obtaining Hydrostatic or Pressure

Design Basis for Fiberglass (Glass-Fiber-

Reinforced Thermosetting-Resin) Pipe and

Fittings

D3034-04a...............Type PSM Poly (Vinyl Chloride) (PVC) Sewer Pipe and Fittings

D3212-96a (2003) e1.....Joints for Drain and Sewer Plastic Pipes Using

Flexible Elastomeric Seals

D3261-03................Butt Heat Fusion Polyethylene (PE) Plastic

Fittings for Polyethylene (PE) Plastic Pipe and

Tubing

D3350-05................Polyethylene Plastics Pipe and Fittings

Materials

D4101-05a...............Polypropylene Injection and Extrusion Materials

F477-02e1...............Elastomeric Seals (Gaskets) for Joining Plastic

Pipe

F679-06.................Poly (vinyl chloride) (PVC) Large-Diameter

Plastic Gravity Sewer Pipe and Fittings

F714-05.................Polyethylene (PE) Plastic Pipe (SDR-PR) Based on Outside Diameter

F794-03.................Poly (Vinyl Chloride)(PVC) Ribbed Gravity Sewer

Pipe and Fittings Based on Controlled Inside

Diameter

33 30 00-4

F894-05.................Polyethylene (PE) Large Diameter Profile Wall

Sewer and Drain Pipe

F949-03.................Poly (Vinyl Chloride) (PVC) Corrugated Sewer

Pipe with Smooth Interior and Fittings

C. American Water Works Association (AWWA):

C105/A21.5-05...........Polyethylene Encasement for Ductile Iron Pipe

Systems

C110/A21.10-03..........Ductile-Iron and Gray-Iron Fittings for Water

C111/A21.11-00..........Rubber Gasket Joints for Ductile Iron Pressure

Pipe and Fittings

C115-99.................Flanged Ductile-Iron Pipe with Threaded Flanges

C116-03.................Protective Fusion-Bonded Epoxy Coatings for the

Interior and Exterior Surfaces of Ductile Iron

Pipe and Gray Iron Fittings for Water Supply

Service

C151-/A21.51-02 Ductile-Iron Pipe, Centrifugally Cast for Water

C153-00 Ductile-Iron Compact Fittings for Water

Services

C508-01.................Swing Check Valves for Waterworks, 2 inches (50

mm) Through 24 inches (600 mm) NPS

C509-01.................Resilient Seated Gate Valves for Water-Supply

Service

C515-01.................Reduced-Wall, Resilient-Seated Gate Valves For

Water Supply Service

C512-04.................Air Release, Air/Vacuum, and Combination Air

Valves for Waterworks Service

C550-05.................Protective Epoxy Interior Coatings for Valves and Hydrants

C600-05.................Installation for Ductile-Iron Water Mains and

Their Appurtenances

33 30 00-5

C605-94.................Underground Installation of Polyvinyl (PVC)

Pressure Pipe and Fittings for Water

C900-97 ................Polyvinyl Chloride (PVC) Pressure Pipe, 100 mm

(4 inches) Through 300 mm (12 inches) for Water

Distribution

C905-97.................Polyvinyl Chloride (PVC) Pressure Pipe and

Fabricated Fittings, 350 mm through 1,200 mm

(14 Inches through 48 Inches), for Water

Transmission and Distribution

C906-99.................Polyethylene (PE) Pressure Pipes and Fittings, 100 mm through 1575 mm (4 Inches through 63

Inches), for Water Distribution

D. American Association of State Highway and Transportation Officials

(AASHTO):

M198-05.................Joints for Concrete Pipe, Manholes, and Precast

Box Sections using Preformed Flexible Joint

Sealants

E. Uni-Bell PVC Pipe Association:

Uni-B-6-98..............Recommended Practice Low Pressure Air Testing of Installed Sewer Pipe

PART 2 - PRODUCTS

2.1 PIPING:

A. Gravity Flow Lines (Pipe and Fittings):

1. Polyvinyl Chloride (PVC):

a. Pipe and Fittings, 100 to 375 mm (4 to 15 inches) in diameter, shall conform to ASTM D3034. Pipe and fittings shall have elastomeric gasket joints providing a watertight seal when tested in accordance with ASTM D3212. Gaskets shall conform to ASTM

F477. Solvent welded joints shall not be permitted.

b. Pipe and fittings, 450 to 900 mm (18 to 36 inches) in diameter, shall be solid wall or have a corrugated or ribbed exterior profile and a smooth interior. Pipe shall conform to the following:

33 30 00-6

1) Pipe and fittings shall conform to ASTM F949 corrugated sewer pipe with a smooth interior. The corrugated outer wall shall be fused to the smooth interwall at the corrugation valley.

Pipe and fitting shall have a smooth bell, elastomeric joints conforming to ASTM D3212, and shall have a minimum pipe stiffness of 350 kPa (50 psi) at 5 percent deflection, when tested in accordance with ASTM D2412. Corrugation shall be perpendicular to the axis of the pipe to allow gaskets to be installed on field cut sections of pipe without the requirement for special fittings.

2) Ribbed wall PVC pipe and fittings shall conform to ASTM F794 ribbed sewer pipe with smooth interior pipe and fittings shall have a smooth bell, elastomeric joints conforming to ASTM

D3212, and shall have a minimum pipe stiffness of 320 kPa (46 psi) when tested in accordance with ASTM D 2412, at 5 percent vertical deflection. Joints shall not leak at 7.6 m (25 feet) of head under 5 percent deflection.

3) Solid wall pipe and fittings shall conform to ASTM F679, pipe and fittings shall gaskets conforming to ASTM F477, and shall be able to withstand a hydrostatic pressure of 345 kPa (50 psi).

2. Ductile Iron Pipe (DIP) for Sanitary Sewer: Shall conform to ASTM

A746, thickness Class 51 unless otherwise shown or specified. Joints on pipe and fittings shall be push-on style and conform to AWWA C110 and AWWA C111, rated for 1.03 MPa (150 psi). Exterior coating shall be approximately 0.025 mm (1 mil) asphaltic coating as specified in

ASTM A746. Interior lining shall be a catalyzed coal tar epoxy, having a minimum thickness of 0.60 mm (24 mils), a permeability rating of 0.13 perms, direct impact rating of 11.3 Nm (100 in-lbs), an abrasion resistance of 20 liters of sand per mil, and dielectric strength of 250 volts per mil. Pipe and fittings shall be polyethylene encased with 0.20 mm (8 mil) polyethylene sheeting per

AWWA C105. Color of polyethylene encasement shall be green.

3. High density polyethylene (HDPE) pipe and fittings 450 mm to 900 mm

(18 inches to 36 inches) shall conform to ASTM F894. Pipe and fittings shall have a smooth interwall and profile exterior, and be

33 30 00-7

Class 100. Joints shall be water tight elastomeric gaskets in accordance with ASTM D3212, or thermal welded joints.

B. Pressure (Force) Lines (Pipe and Fittings):

1. All pipe and fittings used in the construction of force mains shall be rated for a minimum of 1035 kPa (150 psi).

2. Ductile Iron: Pipe shall conform to AWWA C151 and C111 with polyethylene lining. Flange joints shall conform to AWWA C115.

Lining shall be heat-fused mechanical bond polyethylene having a dielectric strength of 250 volts per mil when fully cured. Lining shall be holiday tested in accordance with AWWA C116. The lining shall be a minimum of 1 mm (40 mil) in the barrel of the pipe, and a minimum of 0.25 mm (10 mil) on the bell and spigot area of the pipe.

The lining shall be repaired at all field cuts per the manufacturer’s recommendations. Joints shall be conformed to AWWA

C116. Pipe shall be polyethylene encased per AWWA C105.

3. Ductile iron fittings shall comply with AWWA C110 and AWWA C111.

Fittings shall be polyethylene line, as specified for ductile iron pipe. Ductile iron fittings shall be polyethylene encased per AWWA

C105.

4. Polyvinyl Chloride (PVC): PVC pipe 100 mm to 300 mm (4 to 12 inches) shall conform to AWWA C900, Class 200 (DR 14). PVC pipe larger than

300 mm (12 inches) shall conform to AWWA C905, Class 200 (DR 21).

Fittings for PVC pipe shall be ductile iron.

5. High Density Polyethylene (HDPE) pipe and fittings shall be manufactured from PE 3408, high density, extra high molecular weight polyethylene melting the requirements of ASTM D3350. Pipe shall be manufactured in accordance with ASTM F714, and shall be Class 200

(DR 9). Molded fittings shall be manufactured in accordance with

ASTM D3261 and subject to the test required under ASTM D3261.

Fabricated fittings shall be made by heat fusion jointing of machined shapes cut from pipe, sheet stock, or molded fittings.

Molded and fabricated fittings shall be rated for a minimum working pressure equivalent to the pipe. Joints shall be heat fusion butt joints, flange adapters, or mechanical couplings.

a. Flange adapters shall have adequate through-bore length to be clamped in a butt fusion jointing machine without the use of a

33 30 00-8 stub-end holder. The sealing surface of the flanged shall be machined with a series of V-shaped grooves to restrain the gasket against blow out. Back-up rings and flange bolts shall be rated equal to or greater than the mating pipe. All flange adapters shall be equipped with a stainless steel internal pipe stiffener.

b. Mechanical couplings shall be sleeve style, restrained coupling.

The sleeve and gland shall be epoxy coated and lined and rated for the pressure of the mating pipe. Coupling shall be supplied with stainless steel pipe stiffeners to be installed within the pipe.

2.2 JOINTING MATERIAL:

A. Gravity Flow Lines:

1. Ductile Iron Pipe: Push-on or mechanical joints, AWWA C111, AWWA

C110. Flange joints shall comply with AWWA C115. Flange joints shall only be used in vaults or above-grade.

2. Polyvinyl Chloride (PVC) Pipe (Gravity Use): Joints, ASTM D3212.

Elastomeric gasket, ASTM F477.

3. High Density Polyethylene (HDPE) pipe and fitting joints, ASTM E-

3212, elastomeric gaskets, ASTM F477.

B. Gravity Flow with Secondary Containment: Tapered or straight bell and spigot with adhesive bond. Completed joint shall be equal or greater than the pressure rating of the pipe.

C. Pressure (Force) Main:

1. All joints shall be fully restrained and capable of restraining 50 percent above all loads acting on the joint, but not less than 1035 kPa (150 psi). Thrust blocks shall not be permitted.

2. Ductile iron pipe and fittings, mechanical or push-on, conforming to

AWWA C110 and C111. Restrained joints shall meet the following requirements:

a. Push-on joints shall be restrained by a mechanical locking slot cast integrally in the bell of the pipe or fitting. The spigot shall have a retainer weldment or band. Locking segments, placed in the slots in the bell, shall form a mechanical restraint and prevent the opening of the joint.

b. Mechanical joint restraint shall be incorporated into the design of the follower gland. The restraining mechanism shall consist of

33 30 00-9 individually actuated wedges that increase their resistance to pull-out as pressure or external forces increase. The device shall be capable of full mechanical joint deflection during assembly and the flexibility of the joint shall be maintained after burial. The joint restraint ring and its wedging components shall be made of Grade 60-42-10 ductile iron conforming to ASTM

A536. The wedges shall be ductile iron heat treated to a minimum hardness of 370 BHN. Dimensions of the gland shall be such that it can be used with the standardized mechanical joint bell conforming to AWWA C111 and AWWA C153 of the latest revision.

Torque limiting twist-off nuts shall be used to insure proper actuation of the restraining wedges. The gland shall be specifically designed for the type of pipe (DIP or PVC) connected to the fitting.

3. Polyvinyl Chloride (PVC) Pipe (Pressure Use):

a. Push-on joints shall conform to AWWA C900, C905.

b. Push-on gaskets for pipe, ASTM F477.

c. Restrained joints shall comply with one of the following:

1) Joints to mechanical ductile iron fittings shall comply with the requirements for ductile iron pipe, except the mechanical joint restraint gland shall be specifically designed for use with PVC pipe.

2) Push-on bell and spigot joints shall be retained with retaining rings and thrust rods. The rings shall be ductile iron conforming to ASTM A536. The rings shall be split style with serrated inside face which grips the pipe when the halves of the ring is assembled together. The ring shall not bear directly on the back of the bell. The rods shall be of adequate size and number to resist all axial movement of the joint.

4. High Density Polyethylene (HDPE) pipe and fittings shall be fusion butt welded, flanged, or mechanical couplings as recommended by the manufacturer. Restrained joints shall be limited to fusion welded and flanged.

2.3 MANHOLES AND VAULTS:

33 30 00-10

A. Manholes and vaults shall be constructed of precast concrete segmental blocks, precast reinforced concrete rings, precast reinforced sections, or cast-in-place concrete. The manholes and vaults shall be in accordance with State Department of Transportation or State Roads

Commission standard details, and the following:

1. Precast Concrete Segmental Blocks: Blocks shall conform to ASTM C139 and shall not be less than 150 mm (6 inches) thick for manholes to a depth of 3.6m (12 feet); not less than 200 mm (8 inches) thick for manholes deeper than 3.6m (12 feet) deep. Blocks shall be not less than 200 mm (8 inches) in length. Blocks shall be shaped so that joints seal and bond effectively with cement mortar. Parge structure interior and exterior with 15 mm (1/2 inch) of cement mortar applied with a trowel and finished to an even glazed surface.

2. Precast Reinforced Concrete Rings: Rings or sections shall have an inside diameter as indicated on the drawings, and shall be not less than 1200 mm (48 inches) in diameter. Wall thickness shall conform to requirements of ASTM C76, except that lengths of the sections may be shorter as conditions require. Tops shall conform to ASTM C478.

Top section shall be eccentric cone type. Steps on inside wall shall be in the same plane from bottom of structure to manhole cover.

3. Precast Reinforced Concrete Manhole Risers and Tops: Design, material and installation shall conform to requirements of ASTM

C478. Top sections shall be eccentric. Steps on inside wall shall be in the same plane from bottom of structure to manhole cover.

4. Flat top manhole tops shall be reinforced concrete as detailed on the drawings.

5. Vaults: Reinforced concrete, as indicated on the plans, or precast reinforced concrete. Concrete for precast sections shall have a minimum compressive strength of 35 MPa (5,000 psi) at 28 days, ASTM

A615, Grade 60 reinforcing steel, rated for AASHTO HS20-44 loading with 30 percent impact, and conform to ASTM C857.

6. Mortar:

a. Precast Concrete Segmental Block Structures: By volume, 1 part of

Portland cement, l/4 part lime hydrate, and 3 parts sand.

b. Precast Reinforced Concrete Ring and Riser Structures: By volume, 1 part of Portland cement and 2 parts sand. Water in mixture

33 30 00-11 shall produce a stiff, workable mortar, but shall not exceed 21 L

(5-l/2 gallons) per sack of cement.

7. Flexible sealing compound shall be packaged in extruded preformed shape, sized to completely fill the joint between precast sections, and form permanently flexible watertight seal. The sealing compound shall be non-shrink and meet AASHTO M198.

8. Frames and covers shall be gray cast iron conforming to ASTM A48.

The frame and cover shall be rated for HS20-44 loading, have a studded pattern on the cover, and the words “sanitary sewer”. The studs and the lettering shall be raised 8 mm (5/16 inch). The cover shall be a minimum of 600 mm (24 inches) in diameter and shall have four 19 mm (3/4 inch) vent holes and two lifting slots. The bearing surface of the frame and cover shall be machine finished. The cover shall fit firmly on the frame without movement when subject to traffic.

9. Manhole steps shall be polypropylene plastic coated on a No. 4 deformed rebar conforming to ASTM C478, Polypropylene shall conform to ASTM D4101. Steps shall be a minimum of 406 mm (16 inches) wide and project a minimum of 178 mm (7 inches) away from the wall. The top surface of the step shall have a studded non-slip surface. Steps shall be placed at 300 mm (12 inch) centers.

10. Ladders, brackets and hardware shall be constructed of welded aluminum, rails shall be 10 mm (3/8 inch) by 63 mm (2-1/2 inches) spaced a minimum of 400 mm (16 inches) apart. Rungs shall be 35 mm

(1-3/8 inches) in diameter and have a non-slip surface. Standoffs shall offset the ladder 180 mm (7 inches) from the wall. The ladder assembly shall be rated for a minimum of 2200 N (500 pounds).

2.4 CONCRETE:

Concrete shall have a minimum compressive strength of 20 MPa (3000 psi) at 28 days. The cement shall be Type III conforming to ASTM C150.

Concrete shall conform with the provisions of Division 03 of these specifications.

2.5 REINFORCING STEEL:

Reinforcing steel shall be deformed bars, ASTM A615, Grade 40 unless otherwise noted.

2.6 SEWERAGE WET WELL (LESS THAN 300 GALLONS WORKING VOLUME):

33 30 00-12

A. Provide single wall fiberglass reinforced plastic (FRP) U. L. labeled underground storage tanks as shown on the drawings. Size and fittings shall be as shown on drawings.

B. Loading conditions-tanks shall meet the following design criteria:

1. Internal Load: Tank shall withstand without leakage a 34.5 kpa (5 psi) air pressure test with 5 to 1 safety factor. Contractor shall test prior to installation as this is to test for leakage.

2. Vacuum Test: Every tank shall be tested to 292 mm (11.5 inches) of mercury vacuum by the tank manufacturer to assure structural integrity. Contractor shall submit vacuum test certificate if test by manufacturer at plant.

3. Surface Loading: Tank shall withstand surface HS20-44 axle loads.

4. External Hydrostatic Pressure: Tank will withstand 2.1 m (7 feet) of overburden with the hole fully flooded with a 3.1 safety factor against leaking.

C. Fittings:

1. All threaded fittings shall be of a material of construction consistent with the requirements of the U.L. label and located as per drawings.

2. All fittings shall be of sizes as shown on drawings.

D. Materials: Tanks shall be manufactured with 100 percent resin and glass fiber reinforcement with no sand filters.

E. Dimension:

1. Tank shall have nominal capacity as shown on drawings.

2. Tanks shall have 900 mm (36 inch) ID manway riser with complete cast iron frame and lid at finish grade.

2.7 CONCRETE PROTECTIVE COATING:

A. Concrete coating for the interior of wet wells shall consist of an epoxy blended filler sealer, and a cross linked epoxy phenolic cured, resistant protective coating.

2.8 GATE VALVES:

A. AWWA C509, resilient seated gate valves rated for 1360 kPa (200 psi)

WSP, reduced-wall resilient seated gates valves may be supplied in accordance with AWWA C515. Asbestos packing is prohibited. The interior and exterior of the valve shall be epoxy coated for AWWA C550.

B. Operation:

33 30 00-13

1. Shall turn counterclockwise to open.

2. Underground: 50 mm (2 inch) nut for socket wrench operation.

3. Above Ground and In Pits: Handwheels.

C. Joints: End of valve shall accommodate, or be adapted to, pipe furnished.

2.9 VALVE BOXES:

A. Cast iron extension box with screw or slide-type adjustment and flared base. Minimum thickness or metal shall be 5 mm (3/16 inch). Box shall be of such length as will be adapted, without full extension, to depth of cover required over pipe at valve location.

B. Cast the word "SEWER" on the cover.

C. Provide Three (3) "T" handle socket wrenches, of 16 mm (5/8 inch) round stock long enough to extend 600 mm (2 feet) above top of deepest valve box.

2.10 CHECK VALVES

Check valves shall be swing-check valves conforming to AWWA C508. The interior and exterior of the valve shall be epoxy coated per AWWA C550.

The check valve shall be rated for minimum of 850 kPa (125 psi) working pressure.

2.11 WARNING TAPE:

Standard, .1mm (4Mil) polyethylene 76 mm (3 inch) wide tape detectable type, green with black letters and imprinted with “CAUTION BURIED SEWER

LINE BELOW”.”

PART 3 - EXECUTION

3.1 BUILDING SERVICE LINES:

A. Install sanitary sewer service lines to point of connection within approximately 1500 mm (5 feet) outside of buildings where service is required and make connections. Coordinate the invert and location of the service line with the Contractor installing the building lines.

B. Connections of service line to building piping shall be made after the new sanitary sewer system has been constructed, tested, and accepted for operation by the Contracting Officer Representative. The Contractor shall install all temporary caps or plugs required for testing.

C. When building services have not been installed at the time when the sanitary sewer system is complete, provide temporary plugs or caps at

33 30 00-14 the ends of all service lines. Mark the location and depth of the service lines with continuous warning tape placed 300 mm (12 inches) above service lines.

3.2 ABANDONED MANHOLES STRUCTURES AND PIPING:

A. Manholes and Structures Outside of Building Areas: Remove frame and cover, cut and remove the top of an elevation of 600 mm (2 feet) below finished grade. Fill the remaining portion with compacted gravel or crushed rock or concrete.

B. Piping outside of building areas shall be completely removed have all ends of the piping at the limit of the abandonment and within structures and manholes, plugged with concrete, and abandoned in-place.

C. The Contractor shall comply with all OSHA confined space requirements while working within existing manholes and structures.

D. When the limit of the abandonment terminates in an existing manhole to remain, the flow line in the bench of the manhole to the abandoned line shall be filled with concrete and shaped to maintain the flowline of the lines to remain.

3.3 REGRADING:

A. Raise or lower existing manholes and structures frames and covers, cleanout frames and covers and valve boxes in regraded areas to finish grade. Carefully remove, clean and salvage cast iron frames and covers.

Adjust the elevation of the top of the manhole or structure as detailed on the drawings. Adjust the elevation of the cleanout pipe riser, and reinstall the cap or plug. Reset cast iron frame and cover, grouting below and around the frame. Install concrete collar around reset frame and cover as specified for new construction.

B. During periods when work is progressing on adjusting manholes or structures cover elevations, the Contractor shall install a temporary cover above the bench of the structure or manhole. The temporary cover shall be installed above the high flow elevation within the structure, and shall prevent debris from entering the wastewater stream.

C. The Contractor shall comply with all OSHA confined space requirements when working within existing structures.

3.4 CONNECTIONS TO EXISTING VA OWNED MANHOLES:

A. During construction of new connections to existing manholes, it shall be the sole responsibility of the Contractor to maintain continued

33 30 00-15 sanitary sewer service to all buildings and users upstream. The contractor shall provide, install, and maintain all pumping, conveyance system, dams, weirs, etc. required to maintain the continuous flow of sewage. All temporary measures required to meet this requirement shall be subject to the review of the Contracting Officer Representative.

B. Core existing structure, install pipe at the design invert. Install an elastomeric gasket around the pipe, and grout the interstitial space between the pipe and the core.

C. The bench of the manhole shall be cleaned and reshaped to provide a smooth flowline for all pipes connected to the manhole.

D. Connections and alterations to existing manholes shall be constructed so that finished work conforms as nearly as practicable to the applicable requirements specified for new manholes, including concrete and masonry work, cutting and shaping.

3.5 CONNECTIONS TO EXISTING PUBLIC UTILITY COMPANY MANHOLES:

A. Comply with all rules and regulations of the public utility.

B. The connection to the existing utility shall comply with the standard details and specifications of the public utility company, except as specifically modified on the plans and specifications.

3.6 PIPE SEPARATION:

A. Horizontal Separation - Water Mains and Sewers:

1. Existing and proposed water mains shall be at least 3 meters (10 feet) horizontally from any proposed gravity flow and pressure

(force main) sanitary sewer or sewer service connection.

2. Gravity flow mains and pressure (force) mains may be located closer than 3 meters (10 feet) but not closer than 1.8 m (6 feet) to a water main when:

a. Local conditions prevent a lateral separation of ten feet; and

b. The water main invert is at least 450 mm (18 inches) above the crown of the gravity sewer or 600 mm (24 inches) above the crown of the pressure (force) main; and

c. The water main is in a separate trench separated by undisturbed earth.

3. When it is impossible to meet (1) or (2) above, both the water main and sanitary sewer main shall be constructed of push-on or mechanical joint ductile iron pipe. The pipe for the sanitary sewer

33 30 00-16 main shall comply with the specifications for pressure (force) mains, and the water main material shall comply with Section 33 10 00, WATER

UTILITIES. The sewer shall be pressure tested as specified for pressure

(force) mains before backfilling.

B. Vertical Separation - Water Mains and Sewers at Crossings:

1. Water mains shall be separated from sewer mains so that the invert of the water main is a minimum of 600 mm (24 inches) above the crown of gravity flow sewer or 1200 mm (48 inches) above the crown of pressure (force) mains. The vertical separation shall be maintained within 3 meters (10 feet) horizontally of the sewer and water crossing. When these vertical separations are met, no additional protection is required.

2. In no case shall pressure (force) sanitary main cross above, or within 600 mm (24 inches) of water lines.

3. When it is impossible to meet (1) above, the gravity flow sewer may be installed 450 mm (18 inches) above or 300 mm (12 inches) below the water main, provided that both the water main and sewer shall be constructed of push-on or mechanical ductile pipe. Pressure (Force) sewers may be installed 600 mm (24 inches) below the water line provided both the water line and sewer line are constructed of ductile iron pipe. The pipe for the sewer shall conform to the requirements for pressure sewers specified herein. Piping for the water main shall conform to Section 33 10 00, WATER UTILITIES.

4. The required vertical separation between the sewer and the water main shall extend on each side of the crossing until the perpendicular distance from the water main to the sewer line is at least 3 meters (10 feet).

3.7 GENERAL PIPING INSTALLATION:

A. Lay pipes true to line and grade. Gravity flow sewer shall be laid with bells facing upgrade. Pressure (force) mains shall have the bells facing the direction of flow.

B. Do not lay pipe on unstable material, in wet trench or when trench and weather conditions are unsuitable for the work.

C. Support pipe on compacted bedding material. Excavate bell holes only large enough to properly make the joint.

33 30 00-17

D. Inspect pipes and fittings, for defects before installation. Defective materials shall be plainly marked and removed from the site. Cut pipe shall have smooth regular ends at right angles to axis of pipe.

E. Clean interior of all pipe thoroughly before installation. When work is not in progress, open ends of pipe shall be closed securely to prevent entrance of storm water, dirt or other substances.

F. Lower pipe into trench carefully and bring to proper line, grade, and joint. After jointing, interior of each pipe shall be thoroughly wiped or swabbed to remove any dirt, trash or excess jointing materials.

G. Do not lay sewer pipe in same trench with another pipe or other utility. Sanitary sewers shall cross at least 600 mm (2 feet) below water lines.

H. Do not walk on pipe in trenches until covered by layers of bedding or backfill material to a depth of 300 mm (12 inches) over the crown of the pipe.

I. Warning tape shall be continuously placed 300 mm (12 inches) above sewer pipe

J. Install gravity sewer line in accordance with the provisions of these specifications and the following standards:

1. Ductile Iron Piping: AWWA C111 and C600.

2. Vitrified Clay Piping: ASTM C12.

3. Polyvinyl Chloride (PVC) Piping: ASTM D2321.

4. High Density Polyethylene (HDPE) Piping: Comply with manufacturer’s recommendations with gaskets with fused joints.

K. Gravity Flow Lines with Secondary Containment:

1. Install per manufacturer’s recommendations. Install all pipe centering devices to maintain an interstitial space below the invert of the carrier pipe. Both the carrier and containment pipe shall be tested for leaks.

L. Installation of Pressure (Force) Mains:

1. Sections of piping listed on the drawings shall be fully restrained using approved joint restraint devices. Joint restraint devices shall be installed in accordance with the manufacturer’s recommendations. For devices with twist of nuts, the twist of nuts shall be placed on top of the fitting for the Engineer’s inspection.

33 30 00-18

The Contractor shall torque test all bolts, set screws, identified by the Contracting Officer Representative.

2. Thrust blocks shall not be permitted.

3. Install pressure (force) mains in accordance with the provisions of these specifications and the following standards:

a. Ductile Iron Piping: AWWA C111 and C600.

b. Polyvinyl Chloride (PVC) Piping: AWWA C605.

c. High Density Polyethylene (HDPE) Piping: Per manufacturer’s recommendations.

3.8 MANHOLES AND VAULTS:

A. General:

1. Circular Structures:

a. Precast concrete segmental blocks shall lay true and plumb. All horizontal and vertical joints shall be completely filled with mortar. Parge interior and exterior of structure with 15 mm (1/2 inch) or cement mortar applied with a trowel and finished to an even glazed surface.

b. Precast reinforced concrete rings shall be installed true and plumb. The joints between rings and between rings and the base and top, shall be sealed with a preform flexible gasket material specifically manufactured for this type of application. Adjust the length of the rings so that the eccentric conical top section will be at the required elevation. Cutting the conical top section is not acceptable.

c. Precast reinforced concrete manhole risers and tops. Install as specified for precast reinforced concrete rings.

2. Rectangular Structures:

a. Reinforced concrete structures shall be installed in accordance with Division 03, CONCRETE.

b. Precast concrete structures shall be placed on a 200 mm (8 inch) reinforced concrete pad, or be provided with a precast concrete base section. Structures provided with a base section shall be set on 200 mm (8 inches) thick aggregate base course compacted to a minimum of 95 percent of the maximum density as determined by

ASTM D698. Set precast section true and plumb. Seal all joints with preform flexible gasket material.

33 30 00-19

3. Do not build structures when air temperature is 0 degrees C (32 degrees F), or below.

4. Invert channels shall be smooth and semicircular in shape conforming to inside of adjacent sewer section. Make changes in direction of flow with a smooth curve of as large a radius as size of structure will permit. Make changes in size and grade of channels gradually and evenly. Construct invert channels by one of the listed methods:

a. Forming directly in concrete base of structure.

5. Floor of structure outside the channels shall be smooth and slope toward channels not less than 1:12 (1-inch per foot) nor more than

1:6 (2 inches per foot). Bottom slab and benches shall be concrete.

6. The wall that support access rungs or ladder shall be 90 degrees vertical from the floor of structure to manhole cover.

7. Install steps and ladders per the manufacturer’s recommendations.

Steps and ladders shall not move or flex when used. All loose steps and ladders shall be replaced by the Contractor.

8. Install manhole frames and covers on a mortar bed, and flush with the finish pavement. Frames and covers shall not move when subject to vehicular traffic. Install a concrete collar around the frame to protect the frame from moving until the adjacent pavement is placed.

In unpaved areas, the rim elevation shall be 50 mm (2 inches) above the adjacent finish grade. Install a 200 mm (8 inches) thick, by 300 mm (12 inches) concrete collar around the perimeter of the frame.

Slope the top of the collar away from the frame.

3.9 SEWER AND MANHOLE SUPPORTS, CONCRETE CRADLES:

A. Reinforced concrete as detailed on the drawings. The concrete shall not restrict access for future maintenance of the joints within the piping system.

3.10 WET WELLS (PRECAST CONCRETE):

A. Install the wet well on a 200 mm (8 inches) compacted aggregate base course.

B. Set precast units level and plumb. Install sealant between all precast.

C. Core openings for pipe penetrations and seal with a modular seal. Seal shall be “link-seal” or approved equal.

D. Grout all joints and depressions in the vault. Install concrete protective coating per the manufacturer’s recommendations. The final

33 30 00-20 coating shall be applied in two coats, providing a minimum thickness

.15 - .20 mm (6-8 mils) dry film thickness per coat.

E. Set top of wet well 300 mm (12 inches) above finish grade.

F. Pipe and fittings entering and within the wet well shall be poly lined ductile iron pipe.

G. All pipe penetrations through the walls of the wet well shall be sealed water tight.

3.11 DRY WELL AND VAULTS:

A. Install precast reinforced concrete vaults on a 200 mm (8 inches) compacted aggregate base course. The floor, walls, and top shall be level and plumb.

B. Vaults shall be sized as indicated on the drawings. Orientate vault and internal piping, valves and appurtenances to provide access to all valves and appurtenances for operation and maintenance of the equipment.

C. Paint interior of dry well and vaults with two (2) coats of alkyd enamel masonry paint.

3.12 CLEANOUTS:

A. 150 millimeters (6 inches) in diameter and consisting of a ductile iron

45 degree fitting on end of run, or combination Y fitting and l/8 bend in the run with ductile iron pipe extension, water tight plug or cap and cast frame and cover flush with finished grade. Center-set cleanouts, located in unpaved areas, in a 300 by 300 by 150 mm (12 by

12 by 6 inches) thick concrete slab set flush with adjacent finished grade. Where cleanout is in force main, provide a blind flange top connection. The center of the flange shall be equipped with a 50 mm (2 inches) base valve to allow the pressure in the line to be relieved prior to removal of the blind flange. Frames and covers for pressure

(force) mains shall be 600 mm (24 inches) in diameter.

B. The top of the cleanout assembly shall be 50 mm (2 inches) below the bottom of the cover to prevent loads being transferred from the frame and cover to the piping.

3.13 SETTING OF GATE VALVES:

A. Avoid setting valves under pavement except where shown on the drawings.

B. Clean valve interior before installation.

C. Set valve plumb, restrain ends of valves when indicated on the drawing.

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D. Set valve box cover flush with the finished grade. Valve box shall be centered over the operating nut.

3.14 SETTING OF CHECK VALVES:

A. Check valves shall be installed in a vault, direct burial of check valves shall not be permitted.

B. Check valves shall be set in the horizontal position, with adequate clearance to the structure to allow for movement of the lever and maintenance of the valve.

C. Clean the interior of the valve and check its operation prior to installation.

D. After installation, adjust the weight on the lever to provide proper operation in accordance with the manufacturer’s recommendations.

3.15 INSPECTION OF SEWERS:

Inspect and obtain the Contracting Officer’s Representative approval.

Thoroughly flush out before inspection. Lamp test between structures and show full bore indicating sewer is true to line and grade. Lip at joints on the inside of gravity sewer lines are not acceptable.

3.16 TESTING OF SANITARY SEWERS:

A. Gravity Sewers and Manholes (Select one of the following):

1. Exfiltration Test:

a. Subject pipe to hydrostatic pressure produced by head of water at depth of 900 mm (3 feet) above invert of sewer at upper manhole under test. In areas where ground water exists, head of water shall be 900 mm (3 feet) above existing water table. Maintain head of water for one hour for full absorption by pipe body before testing. During one hour test period, measured maximum allowable rate of exfiltration for any section of sewer shall be

11 L (3.0 gallons) per hour per 30 m (100 feet).

b. If measurements indicate exfiltration is greater than maximum allowable leakage, take additional measurements until leaks are located. Repair and retest.

2. Infiltration Test: If ground water level is greater than 900 mm (3 feet) above invert of the upper manhole, infiltration tests are acceptable. Allowable leakage for this test will be the same as for the exfiltration test.

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B. Pressure (Force) Mains: Test at 690 kPa (100 psi) for two hours.

Leakage shall be per the following:

D. L=J*D*P/4500

Where:

L = Maximum Allowable Leakage in Gallons per Hour

J = Number of Joints in Test Area

D = Diameter of Pipe in Inches

P = Average Test Pressure (Psi)

C. Testing of Fiberglass Sewage Holding Tanks: No leakage at 35 kPa (5 psi) air pressure test with 5:1 safety factor. Test by Contractor after installation.

D. Testing of Concrete Wet Well: No leakage with the wet well completely filled with water for a duration of 4 hours.

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