Huia Water Treatment Plant replacement project

The latest

We have been granted resource consent to build a new water treatment plant on land at the corner of Woodlands Park Road and Manuka Road, Waima. The new plant will replace the adjacent aging Huia Water Treatment Plant which treats 20 per cent of Auckland’s water and at over 100 years old is near the end of its operational life.

The new reservoirs will increase the volume of water stored locally, improving the resilience of the wider water network and accommodating daily demand fluctuations. Our network is served by five treatment plants, numerous reservoirs and pump stations, and a highly connected network of pipes. It means that if one treatment plant has an operational issue, the other treatment plants can help meet Auckland’s water needs. The Huia Water Treatment Plant replacement project is a vital part of this network.

The new plant will have more advanced treatment processes and will be easier to maintain than the current plant. It will be carefully laid out to ensure staff can access each treatment process safely and easily.

• Click here for the decision following the hearing of an application for resource consent under the Resource Management Act 1991

• Click here to view our media release relating to the project

Resource consents

The resource consent for the Huia Water Treatment Plant replacement project was granted just before Christmas 2023. This is required for us to build a new water treatment plant in Waima to replace the original 95-year-old plant.

The conditions of our consent are focused on mitigating adverse effects on the community and the environment, and cover issues like traffic management, noise, hours of operation, and in particular, stringent conditions aimed to prevent any transfer of kauri dieback. Concept design for the water treatment plant is underway. At this stage, we hope to begin construction in 2027.

Parau disposal site consent

A further consent is required for disposing of soil at the existing Parau sludge disposal site. Options for local disposal sites were investigated and the Parau site has been selected as the most suitable option due to its proximity, and because Phytophthora agathidicida (kauri dieback) infection already appeared to be present at the fill site.

Disposing of surplus excavated material to the Parau sludge disposal site also reduces the quantity of material that needs to be transported through Titirangi Village and surrounding communities.

• Click here for the map of the route to the Parau disposal site

• Click here for the Frequently Asked Questions document

• Click here for the Parau sludge disposal flyer

Project background

In August 2019, we submitted our resource consent application to Auckland Council. Council received 497 submissions - eight were neutral, 20 were in support of the project and 469 opposed the application.

• Click here for information on the hearing and resource consent documents.

The hearing of the application (by independent commissioners) commenced in February 2020 and was adjourned to May 2021 to allow us to carry out sampling of the sites for kauri dieback. On the 30 June 2021, resource consents were granted with conditions.

• Click here for more information.

As part of the resource consent process, we commissioned the most comprehensive sampling for Kauri dieback that has been undertaken in Aotearoa. The sampling consisted of over 995 samples and Kauri dieback was found on the site. The report on the sampling results is available here. As a result of the survey, we have refined the methodology to carry out the site works to minimise any risk of movement of Kauri Dieback from the site. For more information click here to refer to our media release.

The replacement plant

It will be similar to the existing plant in the following ways:

Capacity: As with the ageing plant, the replacement plant will treat water from four dams in the Waitakere Ranges. As the capacity of the dams is set, the proposed plant will treat a similar volume of water, meeting up to 20 per cent of our city’s water needs. However, to improve system-wide resilience, the short-term peak production capacity will be increased.

Traffic: The ageing plant has around 10 truck movements per week, with additional traffic from up to 15 staff located at the site during normal working hours. Once its operational, the new plant will have similar traffic movements.

Noise: As with the ageing plant, most of the treatment processes utilise gravity and are non-mechanical so noise can be managed. The design of a replacement plant would minimise any ‘noisy’ components ensuring all regulatory noise limits can be met.

It will be significantly better than the existing plant in the following ways:

Treatment processes: The replacement plant will offer more advanced treatment processes that are better equipped to deal with the changing water quality from the dams.

Maintenance: The replacement plant will be easier to maintain. Processes will be able to be taken out of service for maintenance without affecting the overall performance of the plant.

Safety: The replacement plant will be designed with safety top-of-mind. The layout will ensure staff and vehicles can move safely around the site.

Visual impact: The replacement plant will have a 10 metre buffer zone of vegetation, helping to screen most of the facility. Unlike the old plant, the new one will be architecturally designed with the environment as a consideration to ensure that the buildings blend into their surroundings by using colour and texture treatments. The two reservoirs will be screened from Woodlands Park Road by planting. The northern reservoir will be buried to further reduce any visibility from the road.

Robustness: Unlike the existing structures, the replacement plant will be designed and built to current earthquake standards.

Engaging with our community

We recognise the significance of the proposed construction site and understand why our project is of public interest. For this reason, we are taking great care to engage with the community through numerous channels.

We have held open days at our ageing plant and drop-in events at Lopdell House in Titirangi. We have distributed newsletters to the local community, briefed councillors and local board members, and responded to over 1600 emails.

In 2017, we set up a community liaison group to work with us as we developed the proposal for the plant. We meet regularly to discuss ways to optimise the design, minimise adverse effects and deliver good community outcomes.

The group is made up of representatives from a wide range of organisations: West Auckland Historical Society, Titirangi Protection Group, Waitakere Ranges Protection Society, Titirangi Residents and Ratepayers Association, Auckland Botanical Society, Tree Council, and Forest and Bird Waitakere Branch.