1993 SPECIFICATIONS CSJ SPECIAL SPECIFICATION ITEM Irrigation System

Transcription

1 1993 SPECIFICATIONS CSJ SPECIAL SPECIFICATION ITEM 5335 Irrigation System 1. Description. This Item shall govern for construction of the irrigation system for the crosstimbers "t-ramp' 2. General Requirement. The irrigation system shall be constructed in accordance with the design requirements and details shown on the plans, and in conformity with the requirements of this specification and the following attached Metro division and section specification number Attached Metro Specifications. Metro No. Subject Irrigation System 4. Irrigation System. This is for an automaticallycontrolled irrigation system and includes all pipes, fittings, electrical controllers, accessories and as built drawings. 5. Materials And Construction Methods. The irrigation system materials and construction will be governed by the abovementioned Metro specifications, which follows: Section Sprinkler Irrigation Part 1 - General 1.01 Scope A. Work Included: Furnishing and installing a complete irrigation system. Trenching and backfill. Furnishing and installing backflow prevention devices. Furnishing and installing sleeves for irrigation piping and remote control valves where indicated. Coordination of installation of water meters and taps. Coordination of electrical service to irrigation controller. Inspections And Tests

2 B. Related Work in Other Sections: Record Drawings Submittals - Section Landscape Grading - Section Lawns and Grasses - Section Trees - Section Landscape Maintenance - Section Intent of the Drawings: sprinkler lines shown on the drawings are essentially diagrammatic. Locations of all sprinkler heads, valves, piping, wiring, etc., Shall be established by the Contractor at the time of construction. spacing of the sprinkler heads and quick coupling valves are shown on the drawings and shall be exceeded only with permission of the Engineer Quality Assurance A. Requirements of Regulatory Agencies: 1. All work and materials shall be in full accordance with latest rules and regulations of safety orders of division of industrial safety; the uniform plumbing code and other applicable laws or regulations, including the City of Houston plumbing code. 2. Nothing in these drawings or specifications is to be construed to permit work not conforming to these codes. Should the contract documents be at variance with the aforementioned rules and regulations, notify Engineer and get his instructions before proceeding with the work affected. B. Testing: 1. Preliminary review of completed installation will be made by Engineer prior to backfilling of trenches and during hydrostatic testing. 2. Final review shall be made in conjunction with the final review of lawn, shrub and tree planting. C. Licenses: Installer shall be an irrigator licensed by the State of Texas. D. Notify TxDOT 48 hours in advance when testing will be conducted. conduct tests in presence of TxDOT. E. Hydrostatic Test: See paragraph Submittals (refer also to Section 01300) A. Furnish required copies of manufacturers literature, certifications, and operating instructions for the complete list of materials, for the following Items: 1. Irrigation Controller. 2. Pressure Vacuum Breaker

3 3. Gate Valves. 4. Pipe and Fittings. 5. Remote Control Valves. 6. Valve Boxes. 7. Quick Coupling Valves. 8. Sprinkler Heads. 9. Low Voltage Wiring. 10. Wire Connectors. B. Substitutions: 1. Specific reference to manufacturers' names and products specified in this section are used as standards, but this implies no right to substitute other material or methods without written approval of the Engineer. 2. Installation of any approved substitution is Contractor s responsibility. Any changes required for installation of any approved substitution must be made to the satisfaction of the Engineer and/or Metro and without additional cost to TxDOT or Metro. 3. Approval by Engineer of substituted equipment and/or dimensional drawings does not waive these requirements. C. Record Irrigation Drawings: Contractor shall furnish record drawings of the complete irrigation system in accordance with the general and special conditions. procure from the owner or TxDOT full-sized sepias of contract drawings. Construction drawings shall be on the construction site at all times while the irrigation system is being installed. Contractor shall make a daily record of all work installed during each day. actual location of valves and quick couplers and all irrigation and drainage piping shall be shown on the prints by dimensions from easily identified permanent features, such as buildings, curbs, fences, walks or property lines. Drawings shall show approved substitutions, if any, of material including manufacturer's name, and catalogue number. The drawings shall be to scale and all indications shall be neat. All information noted on the print shall be transferred to the sepia by Contractor and all indications shall be recorded in a neat, orderly way. the record sepia shall be turned over to the Engineer and Metro at or before the final acceptance of the project. D. Spare and Special Tools: Provide TxDOT with six spare sprinkler heads of each size and type, two wrenches for each type of head cover and two wrenches for removal and installation of each type of head

4 E. Water Tap Connections: Installer shall be certified by the City of Houston Water Department to tap water distribution main and to install water meter all in accordance with City of Houston Standards Job Conditions A. Contractor shall acquaint himself with all site conditions. Should utilities or other work not shown on the plans be found during excavations, Contractor shall promptly notify Engineer for instructions as to further action. Failure to do so will make Contractor liable for any and all damage thereto arising from his operations subsequent to discovery of such utilities not shown on plans. b. Contractor shall take necessary precautions to protect site conditions. Should damage be incurred this Contractor shall repair damage to its original condition or furnish and install equal replacement at his expense Final Acceptance: Work under this section will be accepted by Engineer and Metro upon satisfactory completion of all work. Upon final acceptance, Metro will assume responsibility for maintenance of the work Clean Up: Keep all areas of work clean, neat, and orderly at all times. Keep all paved areas clean during installation operations. Part 2 - Materials 2.01 Materials: Materials throughout the system shall be as specified and/or noted on the drawings, new and in perfect condition Pressure Type Vacuum Breaker Assembly: FEBCO 765 P.V.B., one and a half (1 1/2) inch, or approved equal Pipe A. Piping on Pressure Side of Irrigation Control Valves: 1. Two and one-half (2-1/2) inch diameter and smaller - polyvinyl chloride (PVC) , schedule 40 and shall conform to astm d B. Piping on Non-Pressure Side of Irrigation Control Valves: 1. Polyvinyl chloride (PVC) , sdr 21.0, class 200, and shall conform to ASTM D , except one-half (1/2) inch diameter shall be class 315. C. Identification: All piping shall be continuously and permanently marked with the following: 1. Manufacturer's name or trademark, size, schedule, and type of pipe, working pressure at 73 F. and National Sanitation Foundation (N.S.F.) approval

5 2.04 Fittings A. Fittings for Solvent-Welded Pipe: 1. Schedule 40, polyvinyl chloride, standard weight, as manufactured by "SLOANE", "LASCO", or approved equal, to meet ASTM D AND D Threaded PVC Nipples - Schedule 80 PVC. B. Fittings for Swing Joints: 2.05 Gate Valves 1. Supply three (3) Schedule 40 "MARLEX" elbows. 2. Threaded PVC Nipples - Schedule 80 PVC. A. Up to three (3) inch size: 125-pound bronze construction, non-rising stem type, sized to line. "NIBCO" T113; or approved equal Sleeve for Control Wire and Water Line: PVC , Schedule 40 pipe Irrigation Controller: To be as shown on plans Remote Control Valves A. Valve to be of size and manufacturer shown on drawings, slow acting valves. B. Valves to be of same manufacturer as controller Control Wire A. Wire: Solid copper wire, U.L. approved for direct burial in ground. Minimum gauge: 14 UF. ( 12 UF for runs over 1,000 lf.) Common ground wire shall be white. B. Splicing Materials: Scotchlok Spring Connector. "Scotchlok" 3576 Sealing Pack Valve Boxes: To be injection-molded of polyesters and fibrous inorganic temperature resistant components. Box shall provide adequate clearance to operate and service valve. Box and lid to be black, as manufactured by "Ametek", "Christy", "Carson", or equal. A. For remote control valves shall be rectangular, approximately 10 inches x 14 inches inside dimensions by 15 inches deep. B. For gate valves and quick coupler valves shall be round, approximately nine (9) inches inside diameter by 10 inches deep

6 2.11 quick coupling valves A. Valve and key shall be "Rainbird", 33DRC with model no. 33k key or approved equal. B. Furnish two valve keys fitted with three-quarter (3/4) inch swivel hose ells Sprinkler Heads: Heads to be as shown on the drawings, where possible supply with black finish Conduits: All conduits for irrigation mains and laterals shall be six (6) inch schedule 80 PVC, common conduit. Part 3 - Execution 3.01 Layout A. No consideration will be given to any design changes until after the awarding of the contract. Should any changes be deemed necessary after award of contract, for proper installation and operation of the system, such changes shall be negotiated by the Engineer and/or Metro and based upon the unit price schedule where applicable. B. Layout work as accurately as possible to drawings. drawings are diagrammatic to the extent that swing joints, offsets and all fittings are not shown. C. Full and complete coverage is required. Contractor shall make any necessary minor adjustments to layout required to achieve full coverage of irrigated areas at no additional cost to TxDOT or Metro. D. Where connections to existing stubouts are required, make necessary adjustments should stubs be located differently in the drawings. Adjust layout as necessary to install around existing work. E. Where piping is shown to be under paved areas but running parallel and adjacent to planted area, the intent is to install piping in planted areas. Do not install directly over another line in same trench. F. It shall be the Contractor s responsibility to establish the location of all sprinkler heads on all turf areas in order to assure proper coverage of all areas. in no case shall spacing of sprinkler heads exceed distances shown on the drawings and/or those specified. pipe sizes shall conform to those shown on the drawings. No substitutions of smaller pipe sizes will be permitted but substitutions of larger sizes may be approved. All pipe damaged or rejected because of defects shall be removed from the site at the time of said rejection. G. The Contractor will stake out the location of each run of pipe and all sprinkler heads of sprinkler valve locations prior to trenching. Before installation is started in a given area, the Engineer shall check all locations and give his approval

7 3.02 Excavating and Trenching A. Perform all excavations as required for installation of work included under this section, including shoring of earth banks, if necessary. Restore all surfaces, existing underground installations, etc., Damaged or cut as a result of the excavations, to their original condition. B. Should utilities not shown on the plans be found during excavations, Contractor shall promptly notify Engineer for instructions as to further action. Failure to do so will make Contractor liable for any and all damage thereto arising from his operations subsequent to discovery of such utilities. Indicate such utility crossings on the record drawings promptly. C. Dig trenches wide enough to allow a minimum of four (4) inches between parallel pipe lines. Trenches shall be of sufficient depth to provide minimum cover from finish grade as follows: 1. Over pipe on pressure side of irrigation control valve, control wires and quick coupling valves: 18 inches. 2. Over pipe on non-pressure side of irrigation control valve: 12 inches. D. Should existing paving require cutting, saw cut paving a minimum 12 inches wide, compact backfill to 95 percent dry density; dispose of waste off site. Patch to match existing pavement Boring Under Existing Pavements (if required) A. The boring shall proceed from a pit provided for the boring equipment and workmen. Excavation for pits and installation shall be as described under "excavating and trenching". The location of the pit shall not interfere with existing plant materials or structures designated to remain. B. Holes shall be bored mechanically. Where holes required are larger than two (2) inches, the bore shall be completed using a pilot hole. The two (2) inch hole shall be bored the entire length of the crossing and shall be checked on the opposite end for line and grade. If acceptable, this hole shall serve as the centerline for the larger hole to be bored. lateral and vertical tolerance is limited to one (1) inch in 10 feet, provided that the variation be regular and occur only in one direction. C. The use of water or other fluids in connection with the boring operation will be permitted only to lubricate cutting. Jetting shall not be permitted. (in unconsolidated soil formations, a gel-forming colloidal drilling fluid consisting of at least ten (10%) percent of high-grade processed bentonite may be used to consolidate cuttings, seal the hole walls and furnish

8 Lubrication for subsequent removal of cuttings and installation of the pipe.) D. Excavated material will be placed near the top of the working pit and disposed of as required. E. Refer to other authorities for jurisdiction over other installations Water Meter: Install as per the requirements of the local water district and local codes Backflow Prevention Device: Install according to local codes and manufacturer's latest printed instructions Conduits and Sleeves A. Furnish and install conduit where control wires pass under or through walls. Conduits to be of adequate size to accommodate retrieval for repair of wiring and shall extend 12 inches beyond edge of walls. B. Install sleeves for all pipes passing through or under walls, walks and paving as shown on drawings. Sleeving to be of adequate size to accommodate retrieval for repair of wiring or piping and shall extend 12 inches beyond edge of paving or other construction. C. Coordinate Conduit and Sleeve Installation with Other Trades as Required Pipe Line Assembly A. General: 1. Install pipes and fittings in accordance with manufacturer's latest printed instructions. 2. Clean all pipes and fittings of dirt, scales and moisture before assembly. 3. All pipe, fittings and valves, etc., Shall be carefully placed in the trenches. Interior of pipes shall be kept free from dirt and debris and when pipe laying is not in progress, open ends of pipe shall be closed by approved means. 4. All lateral connections to the mainline as well as all other connections shall be made to the side of the mainline pipe. No connections to the top of the line shall be allowed. B. Solvent-Welded Joints For PVC Pipes: 1. Use Solvents and Methods by Pipe Manufacturer. 2. Cure joint a minimum of one hour before applying any external stress on the piping and at least 24 hours before placing the joint under water pressure

9 C. Threaded Joints for Plastic Pipes: 1. Use teflon tape on the threaded PVC fittings except where marlex fittings are used. 2. Use strap-type friction wrench only. Do not use metal-jawed wrench. 3. When connection is plastic to metal, male adapters shall be used. The male adapter shall be hand tightened, plus one turn with a strap wrench. joint compound shall be teflon tape or equal upon approval. D. Threaded Joints for Galvanized Steel Pipes: 1. Factory-made nipples shall be used wherever possible. Field-cut threads in pipes will be permitted only where absolutely necessary; when field threading, cut threads accurately on axis with sharp dies. 2. Use pipe joint compound to male threads only. E. Laying of Pipe: 1. Pipes shall be bedded in at least two (2) inches of finely divided material with no rocks or clods over one (1) inch diameter to provide a uniform bearing. 2. Pipe shall be snaked from side to side of trench bottom to allow for expansion and contraction. one additional foot per 100 feet of pipe is the minimum allowance for snaking. 3. Do not lay PVC pipe when there is water in the trench. 4. Plastic pipe shall be installed in a manner so as to provide for expansion and contraction as recommended by the manufacturer. 5. Plastic pipe shall be cut with PVC pipe cutters or hacksaw, or in a manner so as to ensure a square cut. Burrs at cut ends shall be removed prior to installation so that a smooth unobstructed flow will be obtained. 6. All plastic to plastic joints shall be solventweld joints or slip seal joints. Only the solvent recommended by the pipe manufacturer shall be used. All plastic pipe and fittings shall be installed as outlined and instructed by the pipe manufacturer and it shall be the Contractor s responsibility to make arrangements with the pipe manufacturer for any field assistance that may be necessary. The Contractor shall assume full responsibility for the correct installation

10 3.08 Gate Valves: Group valves together and locate in planted areas where possible. Box shall be flush with finish grade Irrigation Control Valves: install control valves in valve boxes where shown and group together where practical. place no closer than 12 inches to walk edges, buildings and walls. Valve boxes shall be flush with finish grade. Backfill valve boxes and control wire splice boxes with gravel, minimum minimum six (6) inch depth Sprinkler Heads A. Place part-circle rotary pop-up sprinkler heads eight (8) inches from edge of and flush with top of adjacent walks, header boards, curbs, and mowing bands, or paved areas at time of installation. Rotary sprinklers to be installed on a swing joint assembly as detailed. B. Install all spray heads on a swing joint assembly as detailed on the drawings Quick Coupling Valves: quick coupling valves shall be installed on a swing joint assembly as detailed on the drawings. Backfill boxes with gravel, minimum six (6) inch depth Automatic Controller A. Install per local code and manufacturer's latest printed instructions. B. Connect remote control valves to controller in clockwise sequence to correspond with station setting beginning with stations 1, 2, 3, etc. C. Affix controller name (i.e., "controller a") on inside of controller cabinet door with letters minimum of one (1) inch high. Affix a non-fading copy of irrigation diagram to cabinet door below controller name. irrigation diagram to be sealed between two (2) sheets of 20 mil (minimum) plastic. D. Controller shall be grounded Control Wiring A. Install control wires with sprinkler mains and laterals in common trenches wherever possible. Lay to the side of pipe line. Provide looped slack at valves and snake wires in trench to allow for contraction of wires. Tie wires in bundles at 10 foot intervals. B. Control wire splices at remote control valves to be crimped and sealed with specified splicing materials. line splices will be allowed only on runs of more than 500 feet. Line splices to be scotch lok sealing pack. all line splices shall be installed in 10 inch round valve boxes. C. Install a minimum of one (1) extra control wire to the control valve located the greatest distance from the

11 Controller in both directions and label each end blank or as shown on plans Closing of Pipe and Flushing of Lines A. Cap or plug all openings as soon as lines have been installed to prevent entrance of materials that would obstruct the pipe. Leave in place until removal is necessary for completion of installation. B. Thoroughly flush out all water lines before installing heads, valves and other hydrants. C. Test as specified. D. Upon completion of testing, complete assembly and adjust sprinkler heads for proper distribution. E. All sprinkler heads and quick coupling valves shall be set perpendicular to finished grades unless otherwise designated on the drawings, or otherwise specified. Sprinkler heads adjacent to existing walls, curbs and other paved areas, shall be set to grade. sprinkler heads which are to be installed in lawn areas where the turf has not yet been established shall be set one (1) inch above the proposed finish grade. heads installed in this manner will be lowered to grade when the turf is sufficiently established to allow walking on it without appreciable destruction. such lowering of heads shall be done by this Contractor as part of the original contract with no additional cost to TxDOT or Metro Testing A. Make hydrostatic tests when welded PVC joints have cured as per manufacturer's instructions. 1. Pressurized Mains: Completely install water meter, mains, isolation valves and control valves. Do not install laterals. Open all isolation valves. Fill all lines with water and shut off at meter. pressurize the main with air to 70 psi. Monitor gauge for pressure loss for four (4) hours. maximum loss shall not exceed three (3) p.s.i. in four (4) hours. leave lines and fittings exposed throughout testing period. leaks resulting from tests shall be repaired and tests repeated until the system passes. Test all isolation valves for leakage

12 2. Non-Pressure Laterals: Test piping after laterals and risers are installed and system is fully operational. Leave trenches open to detect possible leaks by visual method. Repair any leaks and retest. B. Submit written requests for inspections to the Engineer at least 48 hours prior to anticipated inspection date Backfill And Compacting A. After system is operating and required tests and inspections have been made, backfill excavations and trenches with clean soil, free of debris. B. Backfill for all trenches, regardless of the type of pipe covered, shall be compacted to minimum ninety five (95%) percent density under pavements, eighty five (85%) percent under planted areas. C. Compact trenches in areas to be planted by thoroughly flooding the backfill. Jetting process may be used in those areas. D. Dress off all areas to finish grades Clean Up: Clean up and remove all debris from the entire work area prior to final acceptance to satisfaction of Engineer. 6. Measurement. This Item will be measured as a lump sum unit for a complete system in place as shown on the plans. 7. Payment. The work performed and materials furnished in accordance with this Item and measured as provided under measurement will be paid for at the lump sum price bid for "irrigation system". This price shall be full compensation for furnishing, preparing, handling and installing all materials specified; for all excavation and backfilling; for all labor, tools, equipment and incidentals necessary to complete the irrigation system ready for use