Rotoiti – Rotoma Wastewater Treatment Plant

Rotorua Lakes Council

Greenfield development of a stand-alone wastewater treatment facility servicing the Rotoiti and Rotoma communities to the east of Rotorua city.  A joint venture between Rotorua Lakes Council and Tangata Whenua nestled into the hills with a panoramic vista over Rotoma, this plant is noteworthy for its small footprint, minimal environmental impact and use of appropriate technologies.

Horizon Technology was honoured to be invited by Rotorua Lakes Council to implement all aspects of automation and control of a contemporary membrane treatment system, working alongside head contractor Spartan Construction, designers Mott-MacDonald, technology supplier Suez Australia and operator Trility.

Easily one of the most beautiful locations for a wastewater treatment plant anywhere.

Technology deployed:

  • Siemens S7-1500 process automation controllers
  • Wonderware System Platform SCADA
  • ABB variable speed drives

Key skills demonstrated:

  • Integration of disparate stand-alone vendor packages into a coherent system
  • Off-site simulation and acceptance testing prior to site work
  • Wide-area network integration


From the Client:

It’s not the fact that the guys at Horizon have been assisting us for decades and are gifted at the programming of PLC’s and SCADA that makes them so valuable. The value for us is how they understand us and what we do, what we want and how they can deliver it best. They understand how important keeping sewage flowing 24 hours a day is and the stresses that come with ensuring that. They understand how we need their solutions to respond not only when things are going well, but when the inevitable problems arise on the plant. They understand that as a bunch of WWTP operators we deal with a range of disciplines and that their technical knowledge and experience is vital to us. In fact the guys are so ingrained in our team and our team’s objectives, outsiders are often surprised to hear they aren’t employees.