Akaroa reclaimed water treatment and reuse scheme

Consents are already approved for the new wastewater treatment plant on Old Coach Road, the new pump station at the Childrens Bay boat park and to upgrade the wastewater network of pipes and connections.

Additional consents are needed for the irrigation scheme. Our applications for these have been lodged with Environment Canterbury (ECan) and the Christchurch City Council Planning Team and are publicly notified until 5pm on 9 August 2024.

The new applications seek consent to irrigate treated recycled wastewater to native trees at Hammond Point and Robinsons Bay, and to the Recreation Ground at the northern end of Akaroa. We’re also seeking consent to construct a wetland basin and a storage tank at the paddock at the top of Old Coach Road, and a larger set of storage tanks at the Robinsons Bay site.

Earlier in the project we anticipated also needing land for irrigation at Takamātua but, at the time of applying, that site was not required and is not included in our consent applications.

The applications are for consent to:

•    Discharge treated wastewater to land (to irrigate trees)
•    Store treated wastewater in tanks and in a wetland
•    Store untreated wastewater in a storm buffer tank at the Old Coach Road site
•    Construct a new wetland and storage tanks
•    Discharge treated water to the cricket ground and north Akaroa parks for irrigation

The application package includes all the required forms and various reports and assessments to support the application.  

The consent applications to ECan focus on discharging treated wastewater to land, while the applications to Christchurch City Council relate to land use, including storage of treated wastewater, and earthworks. 

The project team will work with both organisations, to answer questions and clarify information as needed or to provide additional information if asked. 

ECan and the Christchurch City Council’s consent team have publicly notified the consent applications.  As the applicant, Christchurch City Council’s Three Waters Team has no influence on either organisation’s processes. 

See our applications(external link) or learn about the ECan resource consenting process(external link).

Leaky pipes and connections

We've been working to reduce the volume of groundwater and stormwater getting into the wastewater network. Having less of this water in the system will improve the capacity of the network to convey wastewater and reduce the risk of overflows to the harbour in wet weather.

It also reduces the storage capacity needed to hold treated wastewater during periods of wet weather when we are unable to irrigate with the new system. Improving this problem was a high priority for many submitters during our consultation in 2021.  To date, our investigations and repairs have focused on the 17 kilometres of pipes under Akaora’s streets, which form the Council’s part of the network.

We carried out a desktop assessment to determine where inflow and infiltration are likely to occur based on a number of the pipe attributes, including location, age and material.  We then carried out detailed investigations using distributed temperature sensing technology on 12km of wastewater pipework and additional CCTV assessments to increase our knowledge of over 7km of wastewater pipework to identify potential sources of unwanted stormwater into the network. 

We've completed $4.75 million of network improvements and repairs in the Akaroa wastewater network and $1.78 million of repairs in the Duvauchelle wastewater network between 2020 and 2023.  This work targeted unwanted water entering the system through leaky pipes, manholes and household gully traps that receive surface water.

We’ll soon start inspecting drains on private properties throughout Akaroa and Duvauchelle. This will identify damaged or incorrectly installed wastewater drains, downpipes and gully traps, which will contribute to high flows into the wastewater network when it rains. 

Our contractor aims to visit all properties in Akaroa and Duvauchelle before the end of December 2024. If issues are discovered, the contractor will let the property owner know what needs to be fixed.

Only by addressing leaks and other issues on both the Council side and the private side of the wastewater network will we be able to significantly reduce the volume of unwanted water entering the network.

Robinsons Bay planting

We’re about to start planting out the lower parts of the Robinsons Bay irrigation block in preparation for the new irrigation system.

The initial planting will comprise about 56,000 kānuka seedlings in winter this year (2024). This will be followed in winter 2025 by planting about 150,000 more kānuka and another 50,000 locally sourced seedlings of other native species. 

Kānuka was chosen as a hardy colonising species that is well-established in the local area. It also provides shelter for other species to germinate and grow.

We’ll also be improving fencing around this area and improving the access over the next 18 months.

Part of the boat park to close

A corner of the Childrens Bay boat park in Akaroa will close at the end of June 2024 as we prepare to build a new wastewater pump station. 

We've put notices up at the site asking owners of boats, trailers or other equipment stored in the area marked on the map below to move them out of the way. 

The pump station is an essential aspect of the new Akaroa wastewater scheme, and consents are approved. 

Although we don't yet have resource consent for irrigating treated wastewater to land, work on a new pump station and new treatment plant needs to get started because the consent to discharge treated wastewater to Akaroa Harbour expires in May 2030. 

The first stage of work at the boat park site will be to complete geotechnical investigations, the results of which will inform the design of the new pump station. Construction is expected to be underway by the end of 2025.  

Read the full story on Newsline(external link).

Leaky pipes and connections

The physical work for our $3.2 million project in Akaroa to reduce the inflow and infiltration of water from other sources into the wastewater system is complete.

This work targeted unwanted water entering the system through leaky pipes, manholes and household gully traps that receive surface water. Improving this problem was a high priority for many submitters during our consultation in 2021.

Our goal is to reduce the volume of groundwater and stormwater flowing into the wastewater network. Having less of this water in the system will reduce raw sewage overflows to the harbour in wet weather. It will also reduce the storage capacity needed to hold treated wastewater during periods of wet weather when we are unable to irrigate.   

The next stage is to complete one full year of flow data collection. This work is already underway.

When we analyse the data, early in 2024, we'll know how much of a difference the work has made. That will help us decide the next steps to further reduce inflow and infiltration if needed. 

The following is the wording of the Council resolution supporting the Inner Bays Irrigation Scheme option, passed on 10 December 2020.

The Council:

1. Acknowledges that many submitters advocated for a sustainable development approach to water in Akaroa and that the Council recognises the value of water as a precious resource and taonga.
2. Acknowledges that the water supply in the Akaroa area and wider Banks Peninsula will be increasingly under threat as climate change increases and that working towards non-potable reuse is supported by the Hearings Panel and most submitters.
3. Acknowledges the concerns of the community about the poor state of the wastewater network and recommends that the Council aims for less than 20% inflow and infiltration through its work on the Council network and that it also requires private property owners to repair their pipes.
4. Increases the promotion of water conservation measures in Akaroa to reduce the volume of wastewater, including the use of Smart Meters funded as part of the Three Waters Reform funding and notes the support by the Hearings Panel and some submitters for excess water charges to assist with this.
5. Regularly communicates progress on the repairs and of conservation measures to the community, Community Board and the Council and that the name of the project change to the Akaroa Reclaimed Water Treatment and Reuse Scheme.
6. Requests Council Officers to work with the Community Board to establish a Community Reference Group including members from the local Rūnanga to ensure that community concerns about the approved Akaroa Reclaimed Water Treatment and Reuse Scheme are listened to and, where possible, addressed.

In response to question one of the Akaroa Treated Wastewater Options consultation document, 'should we discharge highly treated wastewater from our new treatment plant to land or should we continue to discharge into Akaroa Harbour?'

That the Council:

7. Rejects that Akaroa’s highly treated wastewater is discharged from the new treatment plant to the Akaroa Harbour.
8. Approves that Akaroa’s highly treated wastewater is discharged from the new treatment plant to the land.

In response to question two of the Akaroa Treated Wastewater Options consultation document, 'if it decides to develop a scheme where highly treated wastewater is used on land for irrigation, where would you prefer the Council to irrigate? Inner Bays (Robinsons Bay, Hammond Point, Takamātua), Goughs Bay or Pompeys Pillar?'

That the Council:

9. Approves that Akaroa’s highly treated wastewater is used on land for irrigation at Inner Bays (Robinsons Bay, Hammond Point, Takamātua)
10. Requests Council Officers to investigate and incorporate where practical the following into detailed design of the scheme:
11. Additional wetland site options as part of the detailed design, with the goal of reducing the size of the storage ponds.
12. Maximize the planted areas of native bush to both reduce the size of the ponds and increase biodiversity outcomes.
13. Investigate additional areas for irrigation of public space within the Akaroa catchment with the goal of increasing non-potable use.
14. Future-proofing for potential non-potable reuse.
15. The re-use of the current UV treatment unit in the new treatment plant to enable non-potable reuse.
16. Native tree plantings in Robinsons Bay to avoid key archaeological sites as recommended in the Heritage New Zealand submission and installation of interpretation signage for visitors to the site.
17. Softening the contours of the plantings by following the natural contours of the land, running down gullies where possible and raised boardwalks where appropriate for recreation in new wetland areas.
18. Notes that water conservation and Inflow and Infiltration reduction measures aim to reduce the size of the pond.
19. Requests that Council Officers investigate the use of storage tanks instead of storage ponds and if practical discuss the option with the Community Reference Group.
20. Requests Council Officers to investigate and report back to the Council on the option of a scheme for local employment for the planting and maintenance of the native trees. In response to question three of the Akaroa Treated Wastewater Options consultation document, 'would you support us irrigating public parks in Akaroa with highly treated wastewater?'

That the Council:

13. Approves irrigating public parks and flushing public toilets in Akaroa with highly treated wastewater as part of the scheme.

In response to question four of the Akaroa Treated Wastewater Options consultation document, 'would you like use to explore the feasibility of a purple pipe scheme for Akaroa, so that residential property owners could use the water for garden watering and other non-drinking purposes?'

That the Council:

14. Supports and requests Council Officers to explore the feasibility of a non-potable reuse (purple pipe) scheme for Akaroa, so that property owners could use the water for garden watering and other non-drinking purposes.
15. Requests Council Officers work with the Ministry of Health, the Canterbury District Health Board, Ngāi Tahu and water suppliers that are interested in non-potable reuse to develop non-potable re-use guidelines or standards for New Zealand.
16. Requests Council Officers discuss options for enabling non-potable reuse of treated wastewater with the Council as soon as practicable, should the regulatory framework change.

That the Council:

17. Includes consideration of additional budget in the draft Long Term Plan 2021-2031 to implement the approved Akaroa Reclaimed Water Treatment and Reuse Scheme.

Moved: Councillor Templeton
Seconded: Councillor Coker
Carried
(Councillors Chu, Gough and MacDonald requested that their votes against the resolutions be recorded).

Our work on this project began in 2014. This section gives some background to the project.

2021 Community reference group

The Community Reference Group established for this project has completed its work. Members did a great job, raising issues of concern to the community and suggesting how these could be mitigated or overcome.

The group was made up of five community representatives, two rūnanga representatives and two community board members, with support from two members of the project team and an independent facilitator.

They gave us a wide range of advice and suggestions on the scheme, and ideas for how we could improve certain aspects. They were particularly enthusiastic about the move to use storage tanks instead of storage ponds. These tanks could be covered and sited further up Robinsons Bay valley away from the immediate neighbours.

The group said tanks would be more acceptable to the community as they mitigate risks associated with storage ponds, such as dam break, odour, insects and visual effects. It would also prevent rainwater from adding to the amount of treated wastewater to be irrigated.

The Community Reference Group has documented the work it did, the advice given to us and the reasons behind that advice [PDF, 226 KB]. 

2020 Consultation

We undertook five weeks of community consultation outlining four viable options in August 2020, before the hearings panel recommended and the Council accepted the Inner Bays Irrigation Scheme (Option 1).

• Consultation booklet: Akaroa Treated Wastewater Options(external link)

2015 Resource Consent

We were granted consent to build a new wastewater treatment plant on Old Coach Road, a new pump station at the Childrens Bay boat park and to upgrade the wastewater network of pipes and connections.

However, our applications for consent to construct a new pipe outfall to Akaroa Harbour, and discharge treated wastewater via that pipe outfall, were declined. The hearing commissioners said a harbour discharge was offensive to Ngāi Tahu and that we had not adequately investigated alternatives.

We appealed this decision, but in 2019 we decided to drop the appeal.

• Decision: Read the Hearings Commissioners' decision(external link).
• Newsline: Akaroa wastewater appeal to be withdrawn(external link).

Why the treatment plant is being moved

The existing Akaroa wastewater treatment plant(external link) was built in the early 1960s at Takapūneke Historic Reserve.

It is now due for replacement and needs to be moved because the reserve is a historically and culturally sensitive place.

In 1830, Takapūneke was the site of a massacre. Te Rauparahau, with help from the captain of the British ship the brig Elizabeth, captured the rangitira (chief) of the māori pa, Te Miharanui, and killed about 200 of his people on the site.

It is now widely acknowledged that building a wastewater treatment plant at this site was extremely insensitive. The Council now recognises the area as a historic reserve and worked with Ōnuku Rūnanga in 2018 to develop the Takapūneke Reserve Management Plan(external link).

The new site

A site at the top of Old Coach Road was chosen for the new wastewater treatment plant in 2012.

This was one of two sites recommended by the Akaroa Community Wastewater Working Party and Akaroa/Wairewa Community Board. It was chosen for its proximity to Akaroa and to areas that in future could use treated wastewater for irrigation.

This site was supported by Ōnuku Rūnanga and is now owned by the Council.