for Highway Construction Page 479 of 71 5 SECTION 605 – SEWERS, STORM SEWERS, MANHOLE, VALVE COVERS, AND DRYWELLS
605.01 Description.
Construct sewers and storm sewers with manholes, catch basins, inlets , drywells, connections, and other appurtenances. Adjust and repair manhole and valve covers.
605.02 Materials.
Provide materials as specified i n: Concrete ....................................................................................................................................... 502 Pipes, General .............................................................................................................................. 601 Portland cement ........................................................................................................................... 701 Aggregates .................................................................................................................................. . 703 Grout and Mortar ......................................................................................................................... 705 Pipes ........................................................................................................................................... 706 Metals .......................................................................................................................................... 708 Concrete Curing Com pounds and Admixtures ............................................................................. 709 Geotextiles .................................................................................................................................... 718 Use corrugated PE pipe only for storm sewers as specified in 706.16 and with the following additions:
1.Use Type S pipe .
2.Do not subject a pipeline with couplings to pressure flow. Provide size No. 1, 2a, or 2b coarse aggregate for concrete as specified in 703.02 and ¾ inch minus aggregate for untreated base as specified in 703.04. Provide size No. 4 or 5 coarse aggregate for concrete as specified in 703.02 for drywell drain rock .
605.03 Construction Requirements.
Use only precast concrete manufacturers that hold current certification under the NPCA Plant Certification Program, the PCAA Plan t Certification Program, the ACPA QCast Plant Certifications Program, or the PCI Plant Certification Program.
A.Sewers and Storm Sewers. The Contractor may tunnel or jack to cr oss under cross walks, house drives, or service pipes. Excavate and compact backfill as specified in 210. Lay concrete pipe for sanitary sewer lines beginning at t he lower (downstream) end with the receiving end upstream and with ends fully joined using suitable means to prevent air circulation within the pipeline. Install rubber -gasketed joints as specified in 601.03. Install and test pipes as specif ied in 601.03. for Highway Construction Page 480 of 71 5 Install spiral rib corrugated steel pipe and ABS pipe in accordance with the manufacturer’s written instructions. Test the line for leaks before accepting the sewer line as follows:
1.Close off a secti on with suitable watertight bulkheads.
a.Fill the line with water.
b.Apply 4 feet of head pressure to the line measured from the top of the pipe at the upstream end, and supplying water to the section under test so the water loss may be me asured. The Engineer will not accept the sewer line if the water loss exceeds 200 gallons per inch of pipe diameter per mile per day. Locate and correct any leaks if the loss exceeds the volume allowed. The Contractor may test by the low pressure air method as an acceptable alternate to hydraulic testing as follows:
1.Test installation on runs or sections. The Department will allow preliminary testing before backfilling. Test when t he pipe is in a wet condition.
2.Use an approved apparatus and method recommended by the pipe manufacturer.
3.Prepare the installation being tested, between its plugged ends, by pressurizing it to an internal pressure of 4 psi . Air pressure is defined as the pressure in excess of back pressure on the installation that would occur if the pipe were submerged in water. Hold an air pressure of 4 psi for at least 2 minutes or as long as needed for the pressure to stabil ize.
4.The tested section, when tested on the air pressure drop method, will be if the time required for the pressure to drop from 3.5 to 2.5 psi coincides with ASTM C924. The Contractor may test connections to inlet and outlet structures by blocking off a pipe section of the outlet, filling the structure with water, and observing the water surface drop. To be acceptable, water loss must not exceed 0.002 gallons per inch of inside perimeter of connection per foot of structure height or length per hour with no outside back pressure. Construct manhole covers and rings, catch basins, and inlets as specified in 708.22.
B.Manholes, Valves, Catch Basin s, Inlets , and Drywells. Construct manholes, valve frames and covers, catch basins, inlets , and drywells. Adjust existing manhole and valve frames and covers to the finished pavement grade. Coordinate with the utility owner 5 business days before making adjustments. Replace damaged manhole or valve frames and covers. Install concrete collars around manhole and valve frames. Use Idaho IR 87 to test surface smoothness .
605.04 Method of Measurement.
The Engineer will measure the acceptably completed work as follows:
1.By the foot along pipe centerline, excluding the distance across catch basi ns, manholes, inlets, and other structures where the pipe, or a portion of pipe, is not actually incorporated in the finished product.
2.Manholes, valve frames and covers, catch basins, inlets , and drywells by the each. for Highway Construction Page 481 of 71 5 3. Manhole and valve frame and cover adjustment and replacement by the each. The Engineer will not measure structure excavation and bac kfill.
605.05 Basis of Payment .
The Department will pay for acceptable quantities as follows: Pay Item Pay Unit _____ Storm Sewer Pipe ........................................................................ FT _____ Sanitary Sewer Pipe .................................................................... FT Manholes, Type _____ ........................................................................... Each Catch Basis, Type _____ ........................................................................ Each Inlets , Type_____ ................................................................................... Each Sediment and Oil Trap Manhole ............................................................. Each Sediment Control Catch Basin ................................................................ Each Drywell .................................................................................................... Each Adjust Manhole Covers ........................................................................... Each Adjust Valve Covers ............................................................................... Each Replace Damaged Manhole Frame ........................................................ Each Replace Damaged Valve Risers ............................................................. Each Structure excavation, compacting backfill, and trench zone backfill and pipe bedding zone material are incidental , and included in the contract unit prices. for Highway Construction Page 482 of 715 SECTION 606 – PIPE UNDERDRAINS AND URBAN AND RURAL EDGE DRAINS
606.01 Description.
Provide, plac e, and ins pect pipe underdrains , rural edge drains , and urban edge drain pipes.
606.02 Materials.
Provide materials as specified in: Coarse Aggregate for Concrete (Drain Rock ) (Coarse Aggregate Size 1, 2a, 2b) ....................................................................................... 703.02.C Grout (Mortar) .......................................................................................................................... 705.04 Corrugated PE Drainage Tubing, Perforated and U nperforated .............................................. 706.10 Metallic -Coated Corrugated Steel Underdrains ....................................................................... 706.07 Corrugated Aluminum Pipe for Underdrains ............................................................................ 706.08 PVC Pipe, Perforated and Unperforated .................................................................................. 706.14 Fittings for PE Drainage Tubing .............................................................................................. 706.20 Rodent Protection Devices for Trench Drain ........................................................................... 706.21 Edge Drain Markers ................................................................................................................. 712.10 Subgrade Separation Geotextile , Type III ................................................................................ 718.07 Corrugat ed Steel Pipe, Metallic -Coated, for Sewers and Drains ................................. AASHTO M 36 Provide drain rock that is clean angular quarried or crushed rock. The Department will accept drain rock by certification . Submit quality control test results that represent each 500 tons of drain rock placed, with at least 1 test per contract , including gradation (AASHTO T 27 with no wash required) and sand equivalent (AASHTO T 176) to veri fy the certification. Perform quality control sampling and testing using a qualified independent laboratory and submit the test results. The Contractor may provide a grout product that is on the QPL or submit a proposed mix design for approval. Submit a completed certification ITD-0851 form.
606.03 Construction Requirements.
A.General. Line the trench with geotextil e. Lay perforated pipe with the perforations down. Place drain rock around the pipe and to the elevation over the pipe. Fold geotextile over the drain rock and overlap at least 2 feet on the top and at the drain ends. Place approved backfil l material to the top of the trench and compact. Install geotextile, drainage pipe or tubing, and aggregate backfill as specified or as directed. Place the m aterials as specified over pipe underdrains , urban edge drains , and rural edge drains .
B.Urban Edge Drains . Field -verify locations of urban edge drains in the Engineer’s presence.
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 515–517 of 768.