Akaroa Wastewater Treatment Project Update

The Christchurch City Council recently consulted the Akaroa community on five options for upgrading the town’s wastewater system.

Submissions received during consultation are now available on the Council’s website at ccc.govt.nz/haveyoursay.

Of the 236 submissions received, most favoured Option 4, which involved reusing the town’s treated wastewater via a non-potable ‘purple pipe’ network. ‘Purple pipe’ water would be for uses such as garden watering and car washing.

As the Council’s technical staff were assessing the viability of the ‘purple pipe’ option, a discrepancy in flow readings was noticed. Further investigation has revealed that a flow meter has been recording inaccurate readings.

Head of Three Waters and Waste John Mackie said the readings underestimated the flow of wastewater, especially at times of low flow.

These readings were used by our consultants to estimate the land area needed for the options that involved reusing the wastewater to irrigate pasture and/or trees, and to estimate the costs of each of the five options.

“Two new flow meters are being installed to record new data,” Mr Mackie said. “These flow meters will be calibrated to ensure accurate and validated data is recorded.”

Mr Mackie said the new data should be available to the design team during the week beginning June 19.

“When the new data has been gathered, the design team staff will analyse it and assess any impact on the five options that were consulted on,” Mr Mackie said. “It is possible that when the new data is applied, it may show that design estimates relating to land area and costs have been underestimated.”

This technical error means the project team will not be able to report to the Hearings Panel as planned. It has also left the Council with no option but to seek leave of the Environment Court for more time before presenting alternatives to the harbour outfall option for consideration.

“It is unfortunate that this has happened,” Mr Mackie said.

“However, staff and consultants will continue preparing reliable estimates for the most popular option, the ‘purple pipe’ network. This was overwhelmingly favoured in the submissions received, and we look forward to presenting the community with greater detail on how this might work in Akaroa.”

Mr Mackie said no more information will be available until the new flow data is analysed.

--ENDS—

© Scoop Media