Grey Water

Grey water can be defined as any domestic or workplace wastewater produced, excluding sewage. The main difference between grey water and sewage (black water) is the organic loading, which is much higher in black water than grey water. Enviro Concepts offers solutions to grey water treatment and recycling using biological, chemical and physical processes. For light commercial businesses, the Enviro GWTS (Grey Water Treatment System) offers an approved, revolutionary, natural waste water treatment system. With this system, grey water can be returned safely for reuse in toilets or it can be used for irrigation (watering the gardens) under certain circumstances and guidelines. For manufacturing facilities, we offer the Enviro Concepts EL Series that meets environmental standards and guidelines for recycling water so that it can be re-used for process and washdowns.

Why is Grey Water Treatment Needed?

Sources of grey water include sinks, showers, baths, toilets, clothes washing, etc. Nutrients like Nitrogen and Phosphorous come from urine and detergents that are present in grey water. High level nutrient concentration in water poses a major problem to affected water supplies and our environment.

As it is, grey water need not be treated and it can be sent to the sewer. However, for many businesses, recycling the grey water for reuse is more profitable than the cost of operation and discharge to council sewers. For example, one of our client owns a resort in a remote location and does not have a direct connection to sewers. This client’s project includes treatment for both grey water and black water for reuse in irrigation. The savings from repurposing the wastewater is enough to pay for their water treatment project entirely within the 2nd year. They also benefit from the sustainability of the system that will last them for many years.

Compliance Requirements for Greywater Systems

Greywater systems for commercial projects have to be approved, either through council or by the Department of Infrastructure and Planning and follow the benchmark set out by the Plumbing and Wastewater Code.

In industrial water recycling system, the system is required to match EPA standards and have to meet Class A+ water for it to be reused in industrial processes or irrigation. The Enviro Concepts EL Series is the perfect system to achieve the standards.

Grey water system, Enviro Concepts

Grey Water Reuse Options

Recycled greywater is often used for irrigation or watering gardens. There are rules about what type of irrigation processes you can do with the recycled water. The water can also be reused for wash processes in the house/office or industrial facility, including using it in toilets, etc. In all cases, recycled greywater never gets used as potable water.

Grey Water Treatment Process

The treatment options for greywater could be accomplished with biological, chemical or physical process. Typically for a commercial project, the Enviro GWTS, biological process is used. For industrial facilities, The EL Series uses mostly physical and chemical process to filter the water. The process flows and capacities for both systems are:

ProductsProcessSize CapacityOutput WaterApprovals
Enviro GWTSScreening
Biological Treatment
10 KL/DayA+Queensland Plumbing & Wastewater Code
Enviro EL SeriesScreening
Oil Water Separation/DAF
Media/Membrane Filtration
120 KL/DayA+Up to EPA Standards

Enviro Grey Water Treatment System (Enviro GWTS)grey water system, enviro concepts

Diagram shows top view of grey water and black water treatment system

The Enviro GWTS is an approved, below ground system that uses a biological process to filter and recycle the water. The system can achieve full Nutrient Reduction benchmark and has the highest maximum hydraulic loading of 10,000 L/per day.

The Enviro GWTS process starts with an inlet coarse screening to prevent large debris from entering the Buffer Storage. Water stored gravity flows to multiple GWTS pods. The pods hold different types of media and act like deep bed media filters. The contaminated water passes through the media filters and gets collected by the pipes at the bottom of the pods. The pipes collect and channels pre-treated water to a sump put where it is pumped to a pre-treated storage tank. The last stage of the process is disinfection, and in the diagram shown above it shows UV disinfection. Once disinfected, water is sent to the reuse channel.

For further reading on the Enviro EL Series, visit our webpage or download our EL Specification Sheet.

If you have an enquiry for a greywater system for commercial or industrial facility, send in your questions for a free estimate from our engineers.

Enviro Concepts Wastewater Management Estimate