Water Service & Mains Connection SWMS

Water service and mains connection work involves excavating to expose live or new potable water mains, tapping under pressure or shutting down and cutting in new pipework, installing service connections, meters, valves and hydrants, and reinstating the trench and road surface. The work typically occurs within road reserves and nature strips, requiring open trenches deeper than 1.5 m, operation of excavators and vacuum trucks in close proximity to workers, and encroachment on live traffic lanes. Trench collapse, being struck by plant, uncontrolled release of pressurised water, contact with unidentified electrical or gas services, and vehicle impact are the dominant fatality mechanisms.

Under the Work Health and Safety Regulation 2025 (NSW), this work meets multiple high risk construction work categories under section 291 — trench work deeper than 1.5 m (291(g)), work on or adjacent to a road corridor in use (291(n)) and work involving powered mobile plant (291(o)). Section 299 therefore requires a Safe Work Method Statement to be prepared before the work commences and kept available for inspection. Controls are structured to the hierarchy in section 36, prioritising service location and elimination of unprotected trench entry over reliance on PPE.

Hazards identified

12 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Eliminate unprotected trench entry where possible by using non-man-entry tapping bands, under-pressure tapping machines and above-ground meter assemblies so workers do not enter the excavation.
2. 2Substitute mechanical excavation adjacent to known services with non-destructive digging (hydro-vacuum excavation) within 500 mm of any located utility, consistent with the relevant Dial Before You Dig / Before You Dig Australia asset owner requirements.
3. 3Obtain Before You Dig Australia service plans no more than 30 days old, physically locate and pothole all services, and mark surface with AS 5488 utility location quality levels before mechanical excavation.
4. 4Install engineered trench support (shoring boxes, hydraulic shores or battered/benched profiles) for all excavations deeper than 1.5 m, designed and certified in accordance with AS 2187 and the SafeWork NSW Excavation Work Code of Practice; maintain 600 mm spoil setback.
5. 5Establish a traffic management plan and Traffic Guidance Scheme prepared by a qualified TMP designer to AS 1742.3 and the Transport for NSW Traffic Control at Work Sites Technical Manual, with physical barriers separating workers from live traffic lanes.
6. 6Isolate the water main using the water authority's approved shutdown procedure, confirm zero pressure via bleed valves before cutting, and use thrust restraints and pipe plugs rated for the main's operating pressure during cut-in.
7. 7Control silica dust by wet-cutting concrete and DICL pipe with on-tool water suppression, keeping 8-hour TWA exposures below the workplace exposure standard of 0.05 mg/m³ as required by section 49 of the WHS Regulation 2025.
8. 8Where asbestos cement mains are suspected or confirmed, stop work, engage a licensed asbestos removalist and follow the SafeWork NSW Code of Practice How to Safely Remove Asbestos; do not cut, snap or grind AC pipe dry.
9. 9Establish exclusion zones around operating plant using AS 2550.1 requirements, with a dedicated spotter, positive communication and no-go zones enforced when the excavator slew envelope overlaps the work area.
10. 10Disinfect and swab new mains in accordance with AS/NZS 3500.1 and the water authority's connection standard before commissioning; use approved backflow prevention devices to protect the potable supply.
11. 11Provide PPE as the final layer: hi-vis Class D/N garments to AS/NZS 4602.1, safety footwear to AS/NZS 2210.3, eye protection to AS/NZS 1337.1, hearing protection to AS/NZS 1270, and P2 respirators to AS/NZS 1716 for dust tasks.
12. 12All workers hold CPCCWHS1001 (White Card) and relevant utility inductions; the SWMS is developed in consultation with workers under section 47 of the WHS Act 2011 (NSW), reviewed under section 302 of the WHS Regulation 2025 whenever controls change, an incident occurs or the work method is altered.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

A licensed plumbing contractor is engaged by a builder in Riverstone (north-west Sydney) to connect a new 40-unit residential development to Sydney Water's 150 mm DICL main running under Garfield Road East. The work involves saw-cutting the asphalt, excavating a 2.1 m deep trench in the eastern kerbside lane, exposing the main, installing an under-pressure tapping band with a 100 mm branch, connecting the property service and reinstating the pavement. Before mobilising, the contractor lodges the Traffic Guidance Scheme with Blacktown City Council, obtains Sydney Water accreditation approval, and secures BYDA plans identifying a parallel Jemena gas main 800 mm to the west. On the day, a hydro-vacuum truck exposes both services, an aluminium trench shield is set for the 2.1 m excavation, and a certified traffic controller manages the contraflow. The SWMS is signed by all four crew members, the excavator operator's high risk work licence is verified, and the SWMS is reviewed on-site when the crew elects to switch from open-cut to under-pressure tapping to avoid a full shutdown.

Related legislation

• Work Health and Safety Act 2011 (NSW)
• Work Health and Safety Regulation 2025 (NSW)
• Plumbing and Drainage Act 2011 (NSW)
• Public Health Act 2010 (NSW)
• Roads Act 1993 (NSW)
• Protection of the Environment Operations Act 1997 (NSW)

Frequently asked questions