Greywater recycling in apartment blocks, townhouse complexes and commercial buildings is now feasible using Nubian Water System ’s OASIS greywater recycling processor in the system design. Water solutions engineers are seeking compact, above ground equipment that allows recycling for irrigation or internal reuse in toilets and laundries. Property investors, offering sustainable 'Green Buildings' to environmentally responsible tenants, can install economic OASIS systems that save substantial amounts of drinking water, up to 60% of conventional usage patterns.

Nubian Water Systems launched its OASIS greywater processor late in December 2006 and has a growing number of residential installations in VIC, NSW, ACT, QLD and SA. The systems have been accredited in several states to a level at which the treated water may be used internally in laundries and toilets and for above ground irrigation. Nubian is pressing on with its program to achieve Class A+ accreditation.

Nubian’s OASIS technology is Australian with global patents pending. It uses the well proven wastewater treatment processes of solids separation, biological treatment and ultraviolet disinfection. The biological treatment step is the heart of the technology and is an innovative form of aerated biofilter, which provides very high rate processing and is very robust in its ability to deal with varying and shock loads, which are typical of residential greywater.

Treated water is of a high quality, with BOD and suspended solid levels typically less than 5 ppm. The high UV dosage consistently delivers thermo tolerant coliform levels close to zero. The system is fully automated and is designed to require no user intervention between scheduled service calls. On-line and remote monitoring devices can be added and these can integrate with building automation systems

Greywater recycling offers consistent water availability to overcome drought and water restrictions. Architects can design sustainable buildings which can still offer residents lush gardens and water features, using water that would otherwise be destined for the sewer.

Greywater systems that are above ground and discreet in size, are a recent option in 'Green Buildings'. Another benefit for operators is the reduced load on sewage systems with greywater treated and recycled rather than going to sewer.

The OASIS processor can treat up to 1,500 litres per day. Linking multiple processors in parallel on a skid mounted system, together with a common greywater collection and screening system provides a scalable plant suitable for daily hydraulic loads of up to 15,000 litres per day. Optional ultra filtration, chlorination or RO raises water quality even further. Recycled water can be stored with rainwater in common tanks if
overflows are managed to ensure excess rainwater goes to storm water and excess recycled water goes to sewer.

Nubian is currently developing a larger processor to treat 5,000 litres per day each. A group of these in a common system would occupy a single parking space in a car park.

Property developers will use clusters of these systems in large estates, processing greywater and irrigating common land, gardens and even reticulating into groups of houses. Recycling treated water back into residences can reduce drinking water by more than 40% and sewer discharge by 60% promising substantial savings in reticulation of sewage processing facilities.

OASIS greywater processors are attracting attention from the commercial sector because of the simplicity of integration into engineered sustainable architectural designs. It makes achieving environmentally responsible buildings a lot easier.