Sewer Connection — Safe Work Method Statement
Safe Work Method Statement for connecting a new property sewer drain to a live water authority sewer main or existing junction, including excavation to the main, live-flow control, cut-in or saddle connections and inspection.
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This template covers the point where private drainage meets a live authority sewer. It is separate from general drainage installation because the work is on a live main carrying sewage, often at depth and in a road or easement. A connection usually involves an excavation deeper than 1.5 metres, a possible contaminated or flammable atmosphere from the sewer, and excavators and trucks on site, all of which are high risk construction work. A SWMS is required.
The hazards specific to a sewer connection are trench collapse at the main (sewer mains are often the deepest service on a property), hydrogen sulfide and low oxygen in the trench once the main is opened, and contact with raw sewage carrying bacteria and viruses. Live flows mean the main may need to be blocked, bypassed or pumped while the connection is made, and blockages can surcharge upstream properties. Older mains are often vitrified clay or asbestos cement, and cutting or drilling asbestos cement pipe is asbestos work that needs its own controls. Other services, such as water, gas and electrical cables, often run close to the sewer.
Water authorities control who can connect to their sewers. Most require an approved connection application and may require the work to be done by their own crews or by plumbers and drainers they have accredited, with inspection before backfill. The drainer must hold the licence required in your state or territory, and the work must comply with AS/NZS 3500 and the authority's standards. Check the authority's requirements before starting.
Your SWMS must cover the approval and inspection process, service location, excavation support, atmosphere monitoring, flow control and bypass, asbestos cement pipe handling, sewage hygiene, and emergency response.
Customise this template with the water authority approval number, main material, size and depth, connection method, BYDA reference, trench support system, flow control or bypass arrangements, gas detector details, traffic management, and the licence or accreditation numbers of the workers.
Personal Protective Equipment
High Risk Construction Work Types
- •Work in or near a shaft or trench deeper than 1.5 metres, or a tunnel
- •Work in an area that may have a contaminated or flammable atmosphere
- •Work in an area with movement of powered mobile plant
Risk Assessment
1.Approvals, service location and set-up
| Hazard / Risk | Initial Risk | Control Measures | Residual Risk | Responsibility |
|---|---|---|---|---|
| Striking water, gas or electrical services near the sewer | Catastrophic | Obtain a Before You Dig Australia (BYDA) enquiry and the authority's sewer plans showing the main and junction location and depth. Locate and mark services, and hand dig or vacuum excavate within the tolerance zone of marked services. | Low | Licensed Drainer / Excavator Operator |
| Connection made without approval or to the wrong main | Moderate | Hold the authority's connection approval on site and book the required inspections. Confirm the junction or connection point against the plans before excavation. | Low | Licensed Drainer |
2.Excavation to the sewer main
| Hazard / Risk | Initial Risk | Control Measures | Residual Risk | Responsibility |
|---|---|---|---|---|
| Trench collapse burying workers at the main | Catastrophic | Shore, bench or batter any excavation over 1.5 metres before workers enter, using a shoring system selected for the soil and depth. Keep spoil and plant at least 1 metre from the edge, or further as the shoring design requires. Provide a ladder within easy reach and inspect the trench at the start of each shift and after rain. | Low | Site Supervisor / Licensed Drainer |
| Struck by excavator during digging | High | Keep workers out of the excavator's swing radius and out of the trench while digging. Agree signals with the operator and use a spotter near services. | Low | Excavator Operator |
3.Atmosphere monitoring and flow control
| Hazard / Risk | Initial Risk | Control Measures | Residual Risk | Responsibility |
|---|---|---|---|---|
| Hydrogen sulfide or low oxygen in the trench once the main is opened | High | Monitor the trench continuously with a calibrated, bump-tested four-gas detector worn at breathing height. Ventilate deep trenches with a blower when the main is open. Leave the trench immediately if the alarm sounds and do not re-enter until readings are clear. | Low | Licensed Drainer |
| Sewage flooding the trench or surcharging upstream properties | High | Plan the work for low-flow periods. Use the authority-approved flow control: pipe plugs or bypass pumping sized for peak flow, with someone monitoring upstream levels. Do not leave plugs unattended; remove them when the work stops. | Moderate | Licensed Drainer |
4.Cutting in or fitting the connection
| Hazard / Risk | Initial Risk | Control Measures | Residual Risk | Responsibility |
|---|---|---|---|---|
| Exposure to asbestos fibres when cutting or drilling asbestos cement mains | High | Identify the main material before cutting. For asbestos cement, use non-powered cutting tools or the authority's approved method, keep the pipe wet, wear a P2 respirator and coveralls, and bag offcuts as asbestos waste. Do not use angle grinders or power saws on AC pipe. | Low | Licensed Drainer |
| Contact with raw sewage | High | Wear waterproof gloves, glasses and gumboots. Avoid touching the face. Wash hands before eating or smoking, provide wash water on site, and cover cuts. Workers should talk to their doctor about hepatitis A and tetanus vaccination. | Moderate | All Workers |
| Manual handling of heavy pipes and fittings in the trench | Moderate | Lower pipes into the trench with the excavator using rated lifting gear, not by hand. Work in pairs for heavy fittings. | Low | Licensed Drainer |
5.Inspection, testing and backfill
| Hazard / Risk | Initial Risk | Control Measures | Residual Risk | Responsibility |
|---|---|---|---|---|
| Defective connection causing leaks or infiltration | Moderate | Test the new drain as required by AS/NZS 3500 and the authority. Have the connection inspected before backfill and record the inspection or CCTV check. | Low | Licensed Drainer |
| Collapse during shoring removal and backfill | High | Backfill in layers and remove shoring progressively as the shoring supplier specifies, with no one in the trench as panels are pulled. Compact around the pipe by hand before using a compactor. | Low | Site Supervisor |
6.Reinstatement and decontamination
| Hazard / Risk | Initial Risk | Control Measures | Residual Risk | Responsibility |
|---|---|---|---|---|
| Infection from contaminated tools and PPE | Moderate | Wash down tools and boots, bag disposable PPE, and wash before leaving site. Dispose of asbestos waste at an approved facility. | Low | All Workers |
| Open excavation or unstable surface left after work | Moderate | Reinstate the surface and remove barriers only when the area is safe. Fence any excavation left open overnight. | Low | Site Supervisor |
Relevant Codes of Practice
Worker Acknowledgement
By signing below, I confirm that I have read, understood and agree to comply with this Safe Work Method Statement.