Working with both councils and private developers, Innoflow brings three decades of experience in technical design and construction expertise in decentralised wastewater schemes for unsewered communities around New Zealand.

In older rural towns like Piopio in the Waitomo District which was upgraded by Innoflow, failing septic tanks can have serious consequences for public health and the local environment. New Zealand’s high rainfall and prevalence of poorly drained soils makes this an increasingly likely scenario. 

The use of pressurised liquid only sewers (Prelos™), which convey primary treated liquid from on-lot Prelos processor tanks to AdvanTex® wastewater treatment plants, provide key benefits to developers, councils and homeowners. 

Our flagship project for community wastewater treatment is in Queenstown’s iconic Jack’s Point, which at the time of its conception in 2002 was set to become the largest planned residential community in New Zealand, with resource consent allowing for 1,400 homes. 

The simple modular design makes for fast installation with minimal disruption, easy retrofit for sites with existing septic tanks, and the flexibility to add further treatment units for growing communities and staged developments.  

Prelos schemes with AdvanTex treatment plants are resilient to fluctuating loads, making them ideal in communities with transient workforces and seasonal population peaks. 

Unlike developments that can have multiple types of on-site systems with varying performance, our community systems take the burden of responsibility for maintenance, effluent quality, including nutrient/pathogen reduction away from individual homeowners. They produce consistently high-quality treated effluent for effective reuse and land irrigation, with low operating costs and maintenance requirements. They are visually unobtrusive, very quiet and provide a low whole-of-life cost while meeting regulatory requirements and public health needs. 

We have installed over 70 Prelos schemes (formerly known as STEP, also known as liquid only or effluent sewers) around New Zealand, and there are hundreds more around the world, including Australia and the US. 

Our technology for community treatment plants

After effluent has been collected from each house via gravity (STEG) or pumped (Prelos/STEP), Advanced Secondary Treatment is normally provided by AX100 pods or for sites with limited space the AX-Max treatment plant, which incorporates primary, recirculation and discharge within a single module.

Our AX100 pod systems can be installed in multi-pod arrays to handle the filtered effluent from an entire community of on-site Prelos™ tanks.  We can also use them to design a centralised treatment plant to treat wastewater from a standard gravity sewer system. 

AX-Max units are designed to be a turn key package for remote sites and communities.  They are a fully assembled all-in-one unit, that can be easily transported and can also be scaled up by adding more units to provide treatment to suit the overall flow requirements of the project.