340 SECTION 722
722.01 Description
This work consists of constructing and adjusting manholes, catch basins, and inlets, including the furnishing or resetting of necessary metal frames, covers or gratings, valve boxes, or other accessories to new lines and grades.
722.02 Equipme Nt
Reserved.
722.03 Materials
Item Section Concrete Class AE 802 Precast Reinforced Concrete Pipe Manholes 830.01 A or B Adjustment Rings 830.04 Frames, Tops, Covers, Fittings, and Gratings 834.02 A or B Reinforcing Steel 836.02 A Compose mortar of one part cement to two parts of sand by volume. Lime may be added not to exceed 10 percent of the cement by weight.
722.04 Construction Requirements
A.Precast Reinforced Concrete Manholes, Inlets, and Catch Basins. Construct the joints by one of the following methods: − Mortar; − Rubber Gaskets; or − Cold applied preformed plastic gaskets.
B.Concrete Base. Place the base on firm unyielding ground. Construct the bottom edge of the barrel for manholes, catch basins, and inlets to fit flush on the base. Place mortar in the joint between the base and the barrel. Place mortar to fill the base to the elevation of the outlet invert and slope to drain.
C.Pipe Connections. Place pipe so that the inside end protrudes through the inside wall a minimum of 2 inches. Place mortar around the pipe.
D.Placing Castings.
1.General. Set castings in full mortar beds when using precast concrete adjustment rings. Construct manholes, catch basins, and inlets so that a maximum of 6 inches of adjustment rings are needed to set the casting to grade. 341 2. Manholes. Perform surface preparation and installation according to manufacturer’s recommendations when using high density polyethylene or expanded polypropylene adjustment rings.
3.Catch Basins and Inlets. Use only precast concrete adjustment rings for catch basins and inlets.
E.Backfill. Place backfill in lifts not exceeding 6 inches of compacted material. Compact the material as specified in Section 714.04 A.10, “Compaction Control for Aggregate”.
F.Cleaning. Remove silt and deleterious material from manholes, catch basins, and inlets.
G.Adjustments to Existing Units.
1.General. Make adjustments to the structure walls through the use of an adjustment ring or Class AE concrete so that a seat of proper dimensions may be reconstructed to receive the casting, grating, or cover. If the top of the existing structure is weak and faulty, replace it as directed, and complete the extension.
2.Manholes. Perform surface preparation and installation according to manufacturer’s recommendations when using high density polyethylene or expanded polypropylene adjustment rings.
3.Catch Basins and Inlets. Use only precast concrete adjustment rings for catch basins and inlets.
H.Maintenance of Drainage. If the existing drainage facilities become inoperable before the new drainage system is functioning, provide sufficient temporary pumping and drainage facilities to maintain existing drainage.
722.05 Method of Measurement
The Engineer will measure, completed and in place, as specified in Section 109.01 “Measurement of Quantities” and as follows:
A.Catch Basins and Inlets. The Engineer will measure the base, riser , adjustment rings, casting, cover, and grate as part of the catch basin and inlet.
B.Manholes. The Engineer will measure the base, casting, cover, adjustment rings , and grate as part of the manhole.
C.Manhole Risers. The Engineer will measure manhole risers from the base to the bottom of the precast cover or the casting. 342 722.06 BASIS OF PAYMENT Pay Item Pay Unit Manhole___ IN Each Manhole Tee ___IN × IN Each Manhole Sanitary Each Manhole Riser __ IN Linear Foot Inlet – Type __ Each Adjust Manhole Each Adjust Inlet Each Adjust Utility Appurtenance Each Such payment is full compensation for furnishing all materials, equipment, labor, and incidentals to complete the work as specified. Section 724 343 SECTION 724 WATER MAINS, WATER LINES, AND SEWER LINES
724.01 Description
This work consists of furnishing and installing water, lines, sewer lines, and appurtenances.
724.02 Equipment
Reserved.
724.03 Materials
Item Section Reinforced Concrete Sewer Pipe 830.01 A Ductile Iron Sewer Pipe 830.02 A Plastic Pipe 830.03 Copper Pipe ASTM B 88 Type K Rubber Gaskets ASTM C 443 Gate Valves AWWA C 500 Butterfly Valves AWWA C 504 Concrete – Class AE 802 Use SDR-18, Class 150 PVC pipe that meets the requirements of AWWA C 900. Use joints and fittings that meet the requirements of AWWA. Construct copper services with flared or compression fittings Use gate valves with: − Non-rising stems; − O-ring seals; and − 2 inch operating nuts that open counter -clockwise. Use granular material with 100 percent passing a 2 inch sieve and no more than 35 percent passing a No. 200 sieve for bedding and encasement.
724.04 Construction Requirements
A.General. Comply with the requirements of the North Dakota Plumbing Installation Standards, the NDDEQ , and city ordinances. Do not construct water mains in the same excavated trench as sanitary sewer pipes. Provide at least 10 feet of horizontal clearance between water mains and sewer pipes. If it is not possible to maintain the 10 feet of horizontal clearance or if it is necessary for the water main and sewer pipe cross, provide a minimum vertical separation of 18 inches.
B.Excavation and Trenching. Exca vate trenches to a minimum width of 30 inches or a width of 24 inches wider than the outside diameter of the pipe, whichever is greater. Provide sheathing and bracing to support the trench.
Source: North Dakota Standard Specifications for Road and Bridge Construction, 2022 Edition. Pages 375–377 of 550.