Where have we come from?

Our current wastewater treatment plant:

  • Sited on eastern edge of Lake Rotorua in Sanatorium Reserve - Reserve gifted by Ngāti Whakaue for public purposes under 1880 Fenton Agreement
  • Deconstructs wastewater including domestic sewage, rain, sediment, industrial wastewater & some storm water
  • Deals with about 20 million litres of wastewater per day
  • Wai tātari (treated wastewater) is pumped to Whakarewarewa Forest for discharge via a land spray system
  • Best in NZ at removing nitrogen, but recovered water is still high in phosphorous and pathogens


Council has operated a Land Treatment System (LTS) in Whakarewarewa Forest for the discharge of wai tātari from the Rotorua city wastewater treatment plant (WWTP) since 1991.

Wai tātari is sprayed in the forest and seeps through land in the Puarenga Catchment before ultimately discharging into Te Rotoruanui-a-Kahumatamomoe (Lake Rotorua).

Whakarewarewa Forest is owned by CNI Iwi Holdings Limited (CNI) on behalf of the Central North Island Iwi, being: Ngāi Tūhoe; Ngāti Tuwharetoa; Ngāti Whakaue; Ngāti Whare; Ngāti Manawa; Ngāti Rangitihi; Raukawa; and The Affiliate Te Arawa Iwi and Hapū.

RLC acknowledges that the use of land within Whakarewarewa Forest for the spray system is not consistent with its status as a taonga or the relationship of iwi and hapū with their taonga.

In addition to the cultural effects, nitrogen levels in the treated wastewater discharging through the Puarenga Catchment resulted in an abatement notice. An appeal against that notice was settled by a consent order issued by the Court, requiring RLC to investigate viable alternatives for the discharge of wai tātari from the treatment plant.

Council agreed to move out of the forest by 2019 and the proposal to upgrade the treatment plan and discharge treated wastewater to Arikiroa/Sanitorium Reserve via a culturally designed land contact bed followed several years of engagement, led by a project steering committee.

There was significant iwi and community opposition to the proposal regarding discharge to Arikiroa and a new agreement, Kawenata - Puarenga Catchment of Te Rotoruanui-a-Kahumatamomoe, has now been reached between Rotorua Lakes Council, CNI Iwi Holdings and Te Arawa Lakes Trust.

The kawenata reflects the parties’ commitment to work together towards a new long-term solution for discharge of wai tātari (recovered wastewater), and outlines a process to design and develop a Sustainable Forest Approach (SFA).

This includes upgrading Council’s wastewater treatment plant and use of a set area of land within Whakarewarewa Forest, while the parties continue working towards a long-term solution that will not include use of the forest land.