345 ALASKA 2020 SECTION 626
626-1.01 DESCRIPTION . Construct or reconstruct sanitary sewers and appurtenances to
conform to the Plans. This Section r efers to conduit used for sanitary sewers as “sewer conduit.”
626-2.01 MATERIALS. Use materials that conform to the following:
Bedding and Backfill Subsection 204- 2.01 PVC Pipe Subsection 706- 2.05 Polypropylene Pipe Subsection 706- 2.09 HDPE Pipe Subsection 706- 2.08 Ductile Iron Pipe Subsection 707- 2.05
626-3.01 CONSTRUCTIO N REQUIREMENTS. Complete the sanitary sewer 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 sanitary sewer system. Meet the applicable provisions of Sections 201, 204, and 603 for all clearing and grubbing, excavation, bedding, backfill, conduit, and appurtenances. If sewer condui t is directly connected to or supported by rigid structures such as manholes, it must have a joint or flexible connection located 5 feet or less from the point of connection or support. Lay sewer conduit accurately to the staked line and grade. Install all service connections as indicated on the Plans. Provide suitable fittings and adapters when connecting existing service sewers. Clean all foreign matter from sewer conduit. Keep water out of trenches until joints are completed. Plug or cover open ends of c onduit and fittings when work is not in progress to keep out foreign matter and rodents. Join pipe according to manufacturer’s recommendations, or as detailed on the Plans. When sewer conduit is laid within a 10- foot horizontal radius of an existing or a new water main, and is above or 3 feet below the water main, use cast -iron pipe. Remove trench sheeting and bracing above the elevation of the conduit. Do not pull, remove, or disturb sheeting below the conduit.
626-3.02 TESTING. With the Engineer present, test the sewer for grade, alignment, and leakage.
Grade and alignment must conform to staking with no deviation allowed that would inhibit flow. Test for infiltration if the normal groundwater table lies above the invert of the sewer conduit. Infiltratio n must not exceed 4 gallons per inch of conduit diameter per 1000 feet of pipe per day. Test for exfiltration when no groundwater exists above the conduit invert. Leakage must not exceed 5 gallons per inch of conduit diameter per 1000 feet of pipe per day . Use minimum test pressure of 4 feet of water column above the crown at the upper end of the conduit. Correct all leakage before backfilling. After backfilling, test each run of conduit for obstructions and alignment by placing a light at one end. The l ight must be visible through the sewer conduit at the next manhole. 346 ALASKA 2020 626-4.01 METHOD OF M EASUREMENT. Slopes of 10 percent or less . By the length of the horizontal projection of the conduit from center to center of manholes or cleanouts. Slopes of more than 10 percent . By the length along the centerline of the conduit from center to center of manholes or cleanouts.
626-5.01 BASIS OF PA YMENT. Branch connections and service fittings are subsidiary.
Excavation, bedding, and backfill are paid for under Section 204. Payment will be made under: PAY ITEM Item Number Item Description Unit 626.0001.____ Sanitary Sewer Conduit, ___ Inch LF 626.0002.____ Sanitary Sewer Service Connection EACH 347 ALASKA 2020 SECTION 627 WATER 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.