Wastewater disposal to land in Murupara year-round has been ruled out due to the huge land area that would be required for irrigation.

While seasonal discharge to land may still be a feasible option, around 500 hectares would be necessary for irrigation of treated water over a wet year, according to a report by Whakatāne District Council’s consultants.

Discharge consents for Murupara wastewater treatment plant are due to expire on August 26, 2028.

The council is working in co-design with Te Rūnanga o Ngāti Manawa to replace the plant which has been in operation since 1954.

After treatment, the plant discharges water into the Rangitāiki River where it meets the Whirinaki River. Ngāti Manawa had expressed a desire to explore alternatives to river discharge.

Senior water consents project planner Jessica Sinclair said the council was looking at a long list of all of the options for wastewater treatment and disposal and were working on refining that down to a shortlist.

Her report to the council’s projects and services committee on Thursday said the co-design group had recently visited the Tirau and Putāruru wastewater treatment plants to observe a range of treatment processes in operation. These included membrane treatment, constructed wetlands, and rock filter polishing.

One recent piece of technical work being done as part of that process was a report prepared by Babbage Consultants.

“If we were looking to irrigate all year round to land in Murupara, in a wet year we would need about 500 hectares. I think everyone at the table would recognise that is not going to be feasible,” Sinclair said at Thursday’s meeting.

A shortlist was expected be brought before the elected members shortly for feedback before engagement with the community for wider views.

Water consent replacement work continues

Whakatāne District Council is working to replace several water take and wastewater discharge consents across the district before they expire.

An update on the programme of work was presented at the Projects and Services Committee meeting yesterday.

Most of the council’s main water supply consents expire on October 1 this year, while wastewater discharge consents for Whakatāne, Edgecumbe, Tāneatua and Murupara expire in August 2028.

Several water supply schemes already have replacement consents granted and operational, including Matatā, Tāneatua, Waimana and Rūātoki. Work continues on other schemes, including Whakatāne-Ōhope, Rangitāiki Plains and Murupara.

The Whakatāne, Edgecumbe and Tāneatua wastewater projects remain in the early stages, with background technical work continuing while the council works through future engagement arrangements with iwi and hapū.

The council has also commissioned programme-wide technical assessments to support long-term planning.

These include natural hazard assessments of existing wastewater treatment plant sites, focusing on flood and erosion risk under current and future climate conditions, as well as land discharge feasibility assessments to better understand constraints and opportunities for treated wastewater discharge to land across the district.

The report presented to the committee was for information only and did not seek decisions on project options, funding or changes to levels of service.

Engagement with communities, iwi, hapū and other stakeholders will occur as individual projects progress and when decisions are required.

Further updates will be provided as technical investigations, planning work and engagement continue.