The Christchurch City Council is seeking feedback on four options for dealing with highly treated wastewater from Akaroa.
The Council’s Head of Three Waters and Waste, Helen Beaumont, says the town’s wastewater system is old, in a culturally and historically sensitive place, and will be replaced and relocated.
“We have consents for a new treatment plant we’ll build on land we own in Old Coach Road and for a new pump station in the boat park at Childrens Bay,” she says.
“Identifying possible ways to deal with the highly treated wastewater from the new plant has been challenging but we’ve now got four viable options for people to consider.”
At the moment, treated wastewater from Akaroa is piped 100 metres out into Akaroa Harbour.
However, putting any human waste, no matter how well treated it is, into the harbour is culturally offensive to Ngāi Tahu, whose people customarily use the harbour for mahinga kai, harvesting fish and shellfish.
A consent application to build a new harbour outfall into the middle of the harbour was declined in 2015 because of the cultural effects for Ngāi Tahu of a direct discharge of treated wastewater to the harbour and an assessment that the application had not sufficiently investigated alternatives for disposal of the treated wastewater.
Working with the Ngāi Tahu parties and the working party established by Te Pātaka o Rākaihautū/Banks Peninsula Community Board, the Council has identified three land-based options for dealing with highly treated wastewater from the new treatment plant. The fourth option is a new harbour outfall.
All the land-based options involve using treated wastewater to irrigate new areas of native trees and one option also includes a new wetland area near the treatment plant.
Ms Beaumont says the wastewater coming from the new treatment plant will be treated to a significantly higher level than is possible at the existing plant.
“When we say highly treated, we mean just that – Akaroa’s treated wastewater will be among the highest quality of any in New Zealand, and it will be very safe to use for irrigation,” she says.
The four options are:
• Inner Bays Irrigation Scheme: Using highly treated wastewater to irrigate three new areas of native trees in Robinsons Bay, Takamātua and on Hammond Point and developing a new wetland area to provide additional post-treatment storage and further treatment by naturally occurring processes.
• Goughs Bay Irrigation Scheme: Piping highly treated wastewater through a high-pressure pipeline about 11 kilometres up over hills east of Akaroa to an elevation of 677 metres to irrigate a new area of native trees on land above Goughs Bay.
• Pompeys Pillar Irrigation Scheme: Piping highly treated wastewater through a high-pressure pipeline about 13 kilometres up over hills east of Akaroa to an elevation of 631 metres to irrigate a new area of native trees at Pompeys Pillar.
• Harbour Outfall Scheme: Piping highly treated wastewater, via a new longer outfall pipe and discharging it 1.2 kilometres out into the mid-harbour.
Ms Beaumont says each option has advantages and disadvantages, which are described in the consultation booklet and online when consultation opens on Tuesday, 21 July at ccc.govt.nz/haveyoursay.
Council staff will be available to answer questions at the following information meetings in Akaroa and Christchurch during the consultation period.
• Sunday, 2 August, 2pm-3.30pm, Gaiety Hall supper room, Akaroa
• Tuesday, 4 August, 5.30pm-7pm, Civic Offices first floor function room, 53 Hereford Street, Christchurch
• Monday, 10 August, 5.30pm-7pm, Gaiety Hall supper room, Akaroa
“We want people from Christchurch and Banks Peninsula to have their say on the four options,” Ms Beaumont says.
“While this project is locally very significant to Banks Peninsula people, many Christchurch people have strong ties to the area, and whichever option is chosen by the Mayor and Councillors, it will be funded by all ratepayers.”
• Consultation opens on Tuesday, 21 July and closes on Sunday, 23 August.
Information is available at ccc.govt.nz/haveyoursay or you can pick up a consultation booklet at any Council library or service centre, or call 03 941 8999 or 0800 800 169 to have one sent to you.