Greywater / Recycled Water System Install SWMS

Greywater recycling system installation covers the installation of greywater collection, treatment and reuse systems — the systems that collect greywater from showers, basins and laundries, treat it, and reuse it for permitted non-potable purposes such as irrigation and toilet flushing. It combines the sanitary plumbing with the greywater system, and the defining considerations are the strict separation of the greywater from the drinking water supply, the biological hazards of the greywater, the treatment and the permitted reuse. This document is written on the basis that greywater recycling is carried out by a licensed plumber with the cross-connection-prevention, biological, treatment and approval controls in place.

Greywater recycling is carried out to AS/NZS 3500.2 and the greywater and recycled water requirements, under which the greywater system must be kept separate from the drinking water supply, the reuse identified and limited to permitted purposes, and the greywater treated and managed to the requirements. The cross-connection prevention, the biological hazards, the treatment and the permitted reuse are the considerations. This document coordinates the cross-connection-prevention, biological, treatment and approval controls so the greywater system is installed safely.

Hazards identified

9 hazards covered, sorted by priority.

Control measures

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

1. 1Engineering: keep the greywater system separate from the drinking water supply, with no cross-connection and backflow protection where any connection presents a hazard, to AS/NZS 3500.2 and the greywater requirements.
2. 2Administrative: manage the biological hazard of the greywater with hygiene controls, washing facilities and protective clothing, and prohibition of eating, drinking and smoking until decontaminated.
3. 3Administrative: obtain the greywater and recycled water approval and permitted uses before the work, and install the system so greywater is treated, managed and used only for permitted purposes.
4. 4Engineering: clearly identify the greywater reuse pipework and outlets so they are not mistaken for drinking water, and manage greywater stagnation and microbial growth.
5. 5Engineering: where excavation is involved, locate and protect existing services first and control the excavation to the excavation Code of Practice.
6. 6Administrative: manage any treatment chemicals as hazardous chemicals to their safety data sheets, and use mechanical aids for the system, tanks and equipment.
7. 7Administrative: confirm the separation, treatment, identification and permitted use on commissioning, and test for cross-connection.
8. 8Administrative: ensure the work is carried out and certified by an appropriately licensed plumber, drainer or gasfitter under the relevant state or territory plumbing and gasfitting licensing scheme, with the relevant competencies and a compliance certificate issued where required.
9. 9Administrative: all workers must hold a valid White Card (General Construction Induction Training, CPCCWHS1001) where the work is construction work, with the plumbing, gasfitting, confined space and any other competencies required for the work.
10. 10Administrative: conduct a pre-start toolbox talk covering the day's work, identified hazards, isolations, required PPE and emergency procedures, and record attendance in the consultation section.
11. 11Administrative: consult workers and any health and safety representatives on the work and its risks, record the consultation, and keep this document available at the workplace.
12. 12PPE: eye protection to AS/NZS 1337.1, hearing protection where required, gloves appropriate to the task, high-visibility clothing, and Class I or Class II safety footwear with protective toecap to AS/NZS 2210.3.
13. 13Administrative: review and update this SWMS whenever the work scope changes, after any incident or near miss, when a worker or health and safety representative raises a concern, when new hazards are identified, or at minimum every 12 months.

Applicable Codes of Practice

Worked example

A licensed plumber is engaged to install a greywater recycling system collecting shower and laundry greywater for irrigation. The greywater system is kept separate from the drinking water supply, with no cross-connection and backflow protection where any connection presents a hazard, to AS/NZS 3500.2 and the greywater requirements. The biological hazard of the greywater is managed with hygiene controls, washing facilities and protective clothing. The greywater and recycled water approval and permitted uses are obtained before the work, and the system installed so greywater is treated, managed and used only for permitted purposes. The greywater reuse pipework and outlets are clearly identified so they are not mistaken for drinking water, and greywater stagnation managed. Where excavation is involved, existing services are located and protected first. Any treatment chemicals are managed as hazardous chemicals. The separation, treatment, identification and permitted use are confirmed on commissioning, and the system tested for cross-connection. The records are retained.

Related legislation

• Model Work Health and Safety Act — primary duty of care; the duty to consult workers; the reckless-conduct offence; and notifiable-incident provisions, as enacted in each jurisdiction.
• Model Work Health and Safety Regulations — Section 291 high risk construction work and the SWMS preparation and review duties, and the confined space, excavation, demolition and electrical provisions where applicable, as enacted in each jurisdiction.
• The relevant plumbing and drainage standards AS/NZS 3500 (Parts 0–5), AS/NZS 5601.1:2022 for gas, the pressure piping and pressure equipment standards, the AS 4032 valve standards, and the hazardous chemicals, demolition and asbestos requirements, are called up by the relevant legislation, together with the relevant network utility, insurer and site requirements.
• Plumbing, drainage and gasfitting work is licensed under each state and territory's plumbing and gasfitting licensing scheme, with the relevant competencies for the specialist work, and compliance certification required for notifiable work; electrical work is carried out by a licensed electrician.
• Victoria operates under the Occupational Health and Safety Act 2004 and the Occupational Health and Safety Regulations 2017, with the high risk construction work, confined space, excavation and demolition provisions applying in place of the model instruments.

Frequently asked questions