Guidelines for wash bay water recycling

Wash bays are required for washing down parts, vehicles, containers and other items. This prevents pollutants and disease-causing bacteria from being discharged into the storm water system and thus directly into the environment.

Wash bays come in a variety of forms from a simple temporary structure to a fully roofed permanent construction. But, all of them have the same basic function and objective. Contain the wastewater from wash down activities and treat it to meet trade wast specifications before discharge. Simple forms of treatment include silt traps, while oil separators are more complex treatment processes to clean used wash bay water.

The most highly regulated wash bays are those used for quarantine of imported goods. Authorities in Australia set specific criteria in terms of minimum size, water treatment processes and disinfection. Due to the complexity of the regulations and the high costs to retrofit or install a new water treatment system, it is advisable to partner with an experienced supplier for quarantine wash bays.

Recycling wash bay water makes economic sense and is a sustainable practice. It reduces costs by reducing the amount of wastewater generated for disposal and also reducing the amount of supply water needed. This is especially true if the supply water is potable or drinking water.

The Western Australia Department of Health has developed a guidance document for recycling wash bay water. Although it does not apply to other states in terms of regulations, it provides some helpful tips for recycling wash bay water.

1. Planning for reusing wash down water

Before implementing a wash down water recycling system, it is important to thoroughly plan the project:

• Determine the capacity needed and composition of the effluent water

• Design the system including collection, storage and treatment options as well as liquid waste disposal. This should include what to do in the case of system failure to dispose of wash down water. The design should prevent storm water runoff from entering the system to prevent overload.

• Consult with local authorities and ensure that all regulatory permits and licenses are obtained.

• Develop a communication plan for internal and external communication.

2. Commissioning a wash down wastewater recycling system

Commissioning and testing a wastewater recycling system will ensure that it is operating as per design and meets the license conditions:

• Install, inspect and maintain the system in accordance with local government and the manufacturer’s requirements

• The critical part of commissioning a waste water recycling system is to analyse the water quality to check that it remains within the required limits.

• Even with water recycling, soil and sludge must still be disposed of at a registered facility.

3. Risk Management practices

Risk management practices ensure that adequate precautions are taken and keep employees safe. They include the use of Personal Protective Equipment (PPE), site procedures and training along with a program of regular updates to the site risk assessment.

4. Water quality

The Western Australia guidance note gives specific water quality limits for the use of recycled wash down water. The following criteria must be monitored on a six-monthly basis with records kept for five years:

• E. Coli levels

• PH

• Turbidity

• Disinfection

• BTEX (Benzene, Toluene, Ethyl Benzene, Xylene)

Special requirements for quarantine wash down water recycling

Quarantine wash bays are heavily regulated across all states in Australia. Recycling water must be tightly controlled to ensure that no foreign contaminants reach the Australian environment. Access to a quarantine wash bay must be controlled with no unauthorised vehicles or personnel allowed on the site. They should be sized to facilitate washing of a shipping container. It is critical for the surface of a wash bay in quarantine service to be impervious to liquids. This will prevent ground water contamination through seepage. Operating instructions should ensure that the wash bay is washed down at the end of each day. All waste must be contained on site, screened and treated before discharge.

For more information about quarantine wash bays see the relevant government website.

Contact Cleanawater for more information about wash bays and recycling water

We offer highly technical expertise, excellent quality equipment and a personalised approach to your business’ needs. Our wash bays are Australian made with designs appropriate to the harsh Australian climate. We also offer services and maintenance support across the breadth of Australia. We can easily combine our solutions to suit your specific business, compliance and investment requirements.

Find out more about wash bays or call our expert team on 1800 353 788 today to arrange a consultation.