02940 Irrigation Repair.doc

Base Pavements IDIQ

JCGU 09-1700

DIVISION 02 - SITE WORK

SECTION 02940 - LANDSCAPE IRRIGATION SYSTEM REPAIR

PART 1 – GENERAL:

1.1 REFERENCES: The publications listed below form a part of this specification to the extent referenced. The publications are referred to in the text by basic designation only. All publications shall be the latest version/edition/revision of the documents listed below, in effect on the date of this solicitation, except where a date is given.

IRRIGATION MANUAL

Turf Irrigation Manual

American Society for Testing and Materials (ASTM)

ASTM D 638

Standard Test Method for Tensile Properties of Plastic

ASTM D 1785

Standard Specification for Poly (Vinyl Chloride) (PVC)

ASTM D 2241

Standard Specification for Poly (Vinyl Chloride) (PVC)

ASTM D 2466

Poly (Vinyl Chloride) PVC Plastic Pipe Fittings, Schedule 40

Federal Specifications (Fed Spec)

FS A-A-50498

Valve, Foot, Cast Iron, Bronze and Polyvinyl Chloride (PVC)

NATIONAL ELECTRIC CODE

1.2 SUBMITTALS:

The following shall be submitted in accordance with Specification SECTION 01010:

Product Data: Sprinkler Heads, connections, risers, valves, control valves that are the same or equal to needing repair

PART 2 – PRODUCTS:

2.1 PIPING AND FITTINGS:

2.1.1 PVC pipe: ASTM D1785, Schedule 40 or ASTM D 2241, SDR 13.5 or SDR 17 or SDR 21.

2.1.2 Fittings: Fittings, not including valves or sprinkler heads, shall conform to ASTM D 2466.

2.1.3 Tubing for use with drip emitters shall be either polyethylene or polybutylene and shall have a minimum working pressure of 100 psi at 37 C.

2.2 RISERS:

Risers for pop-up spray heads shall be of the double-swing joint type.

2.3 APPLICATION DEVICES:

2.3.1 Pop-up spray heads shall be of the umbrella type in which the flow is evenly distributed around the perimeter of a flat plate on top of the spray head. The spray head shall be so adjustable as to provide half or full circle patterns and operating range of 20 psi to 90 psi. The flow rate shall be adjustable for gallonage and pressure by an easily accessible regulating screw. All heads shall be Toro, Nelson, Raindial or approved equal.

2.3.2 Drip emitters shall be made of rigid, black, ultraviolet-resistant plastic. Each emitter head shall consist of at least two distinct pieces and be designed for easy and complete disassembly for cleaning. The emitters shall be capable of clog-free operation using water filtered through a 30-mesh screen. Emitters shall be multi-headed and shall be spaced to vary with soil conditions and wetted irrigation area.

2.3.3 In all cases of sprinkler repair, the Contractor shall match existing sprinkler heads in the event the above sprinklers don’t correspond to the existing sprinkler system being repaired.

2.4 VALVES:

2.4.1 Pressure Reducing Valves: One valve shall be installed with each solenoid control valve. The valves shall be hydraulically operated, pilot operated, globe or angle type, and may be actuated either by diaphragm or piston. Valve bodies shall be bronze and shall conform to Fed. Spec. A-A-50498, Type I, Class B Valve, stems shall be stainless steel. Valve discs and diaphragms shall be synthetic rubber. Valve seats shall be bronze. Pilot controls shall be bronze with stainless steel working parts.

2.4.2 Manual System Control Valves: The valve shall be heavy-duty, all brass construction suitable for 150 psi working pressure and shall be a globe, type diaphragm valve of normally closed design.

2.4.3 Valve Boxes: Boxes shall be reinforced concrete box with cast-iron cover. Plastic valve boxes and covers, 9 inch inside diameter and self-draining, may be used as an option when approved by the Contracting Officer and in accordance with ASTM D 638.

PART 3 – EXECUTION:

3.1 GENERAL REQUIREMENTS: An existing underground automatic or manual irrigation system that is need of repair and shall supply complete coverage of the area left after pavement repair shall be Contractor’s design and repaired in accordance with the Turf Irrigation Manual. The Contractor shall be required to possess an irrigator’s license issued by the Texas Board of Irrigators or employ such a licensed irrigator to repair irrigation systems. All existing irrigation systems shall be repaired to a fully operational condition.

3.2 SITE PREPARATION:

The Contractor shall be responsible for the repair and replacement of slopes and vegetation damaged by construction operations.

3.3 EXCAVATION AND TRENCHING:

Trenches shall be of sufficient depth to provide for a minimum of 4 inches of cover for all lines.

3.4 PLACING AND LAYING:

Pipe shall not be laid in water or when trench conditions are otherwise unsuitable for the work. Water shall be kept out of the trench until the material in the joints has hardened or until caulking or jointing is completed. When work is not in progress, open ends of pipe, fittings, and valves shall be securely closed so that no substance will enter the pipes or fittings. All connections between plastic pipe and metal valves shall be made with threaded fittings and plastic adapters. Pipe and fittings shall be thoroughly cleaned of all dust, dirt and moisture before assembly. Pipe ends left for future connections shall be valve, plugged, or capped, and anchored as shown or as directed.

3.5 TESTING:

Operational Test: The system shall be tested to demonstrate functional efficiency.

3.6 CONTROLLERS:

Contractor shall provide all electrical connections to maintain a complete usable irrigation control system. All wiring shall be repaired by the Contractor. The sprinkler system shall be tested for complete operation to the satisfaction of the Contracting Officer prior to final inspection. All electrical work shall comply with the National Electric Code.

3.7 BACKFILL AND COMPACTION:

After the irrigation system is fully operational and all required tests and inspections have been performed and approved, the excavations and trenches shall be backfilled with layers of clean soil, free of rubbish and large rocks. Each layer shall not exceed eight (8) inches of loose depth and shall be compacted until uniform compaction is obtained. All areas shall be smooth and dressed to final grade.

END OF SECTION

Section 02940 – Page 1 of 4