627WATER SYSTEM

627-1.01 DESCRIPTION . Furnish and place wat er main improvements and replacements,

including all appurtenances, as shown on the Plans or specified in this Section. Remove, salvage and reinstall or abandon existing fire hydrants, valve boxes, and water meters, as specified. The term “water conduit” r efers to all conduits used for water mains. The term “service pipe” refers to service lines.

627-2.01 MATERIALS. Use materials that conform to the following:

Bedding and Backfill Subsection 204- 2.01 Concrete for Thrust Blocks Subsection 550, Class W HDPE Pipe Subsection 706- 2.08 Ductile Iron Pipe Subsection 707- 2.05 Service Pipe Subsection 707- 2.06 Corporation Stops Subsection 712- 2.09 Gate Valves Subsection 712- 2.10 Valve Boxes Subsection 712- 2.11 Hydrants Subsection 712- 2.12 CONSTRUCTION REQUIREMENTS

627-3.01 GENERAL. Complete the water system and make sure it operates properly at the time

of acceptance of the work. Furnish and install all incidental parts not shown on the Plans or specified in this Section that are necessary to complete the water system. Meet the applicable provisions of Sections 201, 204, and 603 for all clearing and grubbing, excavation, bedding, backfill, conduit, and appurtenances. Consult the Plans for estimated locations of existing sewers, water mains, and other utilities near the construction. Use this data for information only. The Department does not guarantee their accuracy. Confirm and mark the exact locations of all existing utilities before starting work. Excavate, bore, or probe by hand ahead of your work where necessary to determine the exact location of underground conduit or other features that might interfere with construction. Support and protect conduits or other services that cross the trench. Immediately repair or replace any existing utilities that you break or damage. Immediately replace any existing valves, valve boxes, or water lines that you break or damage. Notify the local Fire Department at least 24 hours before removing or interrupting service to fire hydrants. Give at least 24 hours’ notice before interrupting water service to any area. Restore disrupted water service as soon as possible, or make temporary service connections. Use hoses or other suitable methods. If your operations cause service interruptions, you are responsible for all damages. Furnish and install concrete thrust blocks as shown on the Plans or specified in this Section. Place blocks against firm natural ground at the trench site. When the trench is in soft, unstable soil, remove the soft soil and replace it with a ballast backing large a nd heavy enough to resist the thrust. Connect to existing water lines and structures, avoiding contamination of water in lines that are in use. 348 ALASKA 2020 Where water mains under this contract approach within 10 feet horizontal clearance and are below or less than 3 feet above existing sanitary sewers, encase the sanitary sewer with a jacket of Class W concrete 3 inches thick for 10 feet on each side of the crossings, as shown on the Plans. Concrete encasement is not required if the existing sewer is constructed of ductile iron pipe with joints at least 8 feet from the water main, or if you replace the existing sewer with such ductile iron pipe.

627-3.02 INSTALLATIO N OF CONDUIT. Install conduit and fittings according to these

Specifications or the manufacturer's rec ommendations. Lay conduit to the grades and lines shown on the Plans. Remove all foreign matter from conduit interiors before lowering conduit into the trench. When work is not in progress, securely close all open ends of conduit and fittings to keep out t rench water, earth, rodents or other substances. Keep trenches dry to avoid laying conduit in water. Do not lay conduit when weather or trench conditions are unsuitable. Keep water away from new joints, until the joint materials have hardened. Use methods to cut conduit that will produce tight joints and will not damage the conduit. Inspect conduit before lowering it into the trench. Replace defective, damaged, or unsound conduit. Place conduit bedding to conform to plan details. Place bedding, if required, to give conduit a uniform bearing for its full length. Do not permit couplings to rest on solid or original trench bottoms. Conduit bends must not exceed the manufacturer’s recommended limits. If the specified or required alignment requires deflections beyond the limits, furnish special bends or enough shorter lengths of conduit to provide angular deflection within the limits. Use standard lengths of conduit except where fittings require short lengths, or where conduit passes through a rigid structure. Make service and other connections to conform to the Plans. Valve, plug or cap conduit ends for future connections as shown on the Plans and provide thrust blocks.

627-3.03 FIRE HYDRAN TS. Install, relocate, or adjust fire hydrants to the locations and gr ades

shown on the Plans. Where required, furnish and install new fire hydrant extensions and any required conduit. Clean all foreign matter from inside hydrants before installation. Connect the hydrant to the main with 6- inch ductile iron conduit or the same size as the main, whichever is smaller. Provide with an auxiliary valve and cast iron valve box of the same size as the connecting conduit. Use a mechanical connection between the hydrant and the auxiliary valve. Set hydrants at elevations that drain the connecting conduit to the main. Set the hydrant on a slab of stone or concrete at least 4 inches thick and 15 inches square. Firmly block the back of the hydrant with concrete at least 1 square foot in area against the vertical face of the trench. If the character of the soil does not allow the hydrant to be securely wedged, use bridle rods and rod collars of at least 3/4 inch stock and coated with acid- resisting paint. 349 ALASKA 2020 Place at least 7 cubic feet of approved broken stone or clean gravel around the bas e of the hydrant to ensure drainage. Thoroughly compact the backfill around hydrant to the grade line in a satisfactory manner. Tighten stuffing boxes and inspect the hydrants in opened and closed positions to make sure that all parts are in working condit ion. When removing a fire hydrant from an existing main, plug the tee in the main and test for leakage according to Subsection 627- 3.06. Adjust existing fire hydrants for grade, using barrel extensions according to the hydrant manufacturer's recommendations.

627-3.04 VALVES. Install gate valves as shown on the Plans, on a firm base, and plumb.

Remove all foreign matter from the interior before installation.

627-3.05 VALVE BOXES . Install valve boxes over the gate valves as shown on the Plans. Center

box over valve and rest base section on well -compacted backfill. Set top section to allow equal movement above and below finished grade, with final elevation 1 inch below finished grade. Set top of base section approximately on line with nut at top of valve stem. The entire assembly must be plumb. Place a concrete collar on valve boxes installed in pavement, as shown on the Plans. Adjust existing valve boxes by raising or lowering to conform to the final grade and the details shown on the Plans. Salvage and reuse the existing cast iron valve box and cover. If the valve box is adjustable, adjust it with adaptable extension pieces. If the valve box is constructed with steel conduit, weld additional steel conduit to raise the cover. Lower by cutting the existing valve box pipe.

627-3.06 TESTING WAT ER SYSTEM. Test all water main and service connection work for both

pressure and leakage after laying. Leave conduit joints fully exposed. Place only enough backfill between joints to hold the conduit in place during testing. Test services before insulation. Open corporation stops after successful tests. Conduct all tests with the Engineer present. Furnish all testing equipment, labor, materials, and supplies. The Engineer has the right to test and approve all gauges used. Where connection is made to an existing main with no valve present, blank off or plug the outlet leading to the existing main before testing. Conduct tests after completing installation of the system or any portion thereof, before backfilling and after thoroughly flushing the test portion. Fill all lines with water and eliminate all air. Use test pressure equal to the strength classification of the pipe. Use either pneumatic or hydraulic pressure. Maintain pressure on the tested portion for at least 2 hours. Allowable leakage during the test must not exceed the amount established by the AWWA. If visible leakage other than minor sweating occurs, immediately stop the test and tighten the joint to eliminate leakage when pressure is resumed. Replace leaking fittin gs, nipples, or lengths of conduit. Do not caulk or use paints, asphalts, enamels or other types of compounds to eliminate leaks. Complete backfilling after acceptance of the tests.

627-3.07 DISINFECTIO N. After acceptance of pressure and leakage tests, dis infect all portions of

the water system, including valves and stops and any portion of the existing connecting system that may have been contaminated during construction. 350 ALASKA 2020 Use calcium hypochlorite as the disinfecting medium. Use “HTH,” Perchloron, or a simi lar commercial product with approximately 70 percent available chlorine. Make a 5 percent solution by mixing 5 percent of powder with 95 percent water (by weight). Mix the solution into a paste, thin it to slurry by adding water, and add it to the system. Place enough disinfecting material in the system to ensure a chlorine dosage of 50 ppm. This dosage is equivalent to 10 ounces of commercial hypochlorite powder to each 1,000 gallons of water. After adding the chlorine solution, open and leave open all taps, valves, etc., until you notice a strong chlorine odor in the water coming from the outlets; then close the taps, valves, etc. Keep chlorinated water in the system for at least 24 hours; then thoroughly flush the system. During the retention period, oper ate all valves, stops, and other appurtenances to assist disinfection. After treating the system, thoroughly flush. Then take samples from representative points in the system. Place samples in sterile bottles and submit them to proper authorities as direct ed for bacteriological examination. If the bacteriological examination report is unsatisfactory, repeat disinfection until you obtain satisfactory results.

627-4.01 Method of M Easurement.

627-5.01 BASIS OF PA YMENT. Barrel extensions for fire hydrant adjustment are subsidiary.

The contract prices for Fire Hydrant Installation, Relocation, and Removal include the tee in the main, auxiliary gate valve with service box, conduit bet ween the fire hydrant and the gate valve and all fittings and materials required. If no item for water conduit exists, then all conduit removal or installation required between the main and the auxiliary gate valve is subsidiary The contract price for Wat er Service Connection includes installation of a curb stop, valve box, service pipe and connection to a new or existing water main with a service saddle, tapped coupling or corporation stop, as shown on the Plans. Excavation, bedding, and backfill are pai d for under Section 204. Clearing and grubbing, landscaping, disinfection, testing, couplings and/or thrust blocks, and encasement or replacement of existing sewer lines are subsidiary. Any costs involved in service changeovers and providing temporary water service are subsidiary. Removing or abandoning existing water lines or appurtenances designated on the Plans is subsidiary. 351 ALASKA 2020 Payment will be made under: PAY ITEM Item Number Item Description Unit 627.0001.____ Ductile Iron Water Conduit, ___ Inch, C lass ___ LF 627.0002.____ Steel Water Conduit, __ Inch LF 627.0003.____ Install Valve Box EACH 627.0004.____ Fire Hydrant Adjustment EACH 627.0005.____ Fire Hydrant Installation EACH 627.0006.____ Fire Hydrant Relocation EACH 627.0007.____ Fire Hydra nt Removal EACH 627.0008.____ Water Service Connection EACH 627.0009.____ Gate Valve, ___ Inch EACH 627.0010.____ Adjustment of Valve Box EACH 352 ALASKA 2020 SECTION 630 GEOTEXTILE FOR EMBAN KMENT AND ROADWAY SEPAR ATION, STABILIZATIO N AND REINFORCEMENT

630-1.01 DES CRIPTION. Prepare ground surface, and furnish and place geotextil es for

separation, stabilizat ion, and/or reinforcement as shown on the Plans.

630-2.01 MATERIALS. Use materials that conform to the following:

Geotextiles and Sewn Seam Strength Subs ection 729-2.01 Sewing Thread. Use high strength polypropylene, or polyester. Do not use nylon thread. Use thread of contrasting color to that of the geotextile itself.

630-3.01 Constructi On Requirements.