Mairangi Bay Pump Station replacement project

We are building a replacement pump station to reduce wet-weather overflows, creating cleaner beaches and a better environment.

Start-finish: June 2021 - mid-2023
Location: End of Sidmouth Street and Montrose Terrace, Mairangi Bay
Status: Construction

View newsletter

What’s happening now?

We’ve had a big start to 2022 and are celebrating an important milestone having just completed the piling to create the shaft wall. The piling machine created the circular wall which will eventually be the underground portion of the pump station. The wall is important as it keeps water out of the shaft during digging.

We are continuing to move forward and dig out the inside of the shaft. We have removed the large drilling machine from site and will be bringing in excavators to begin digging. This stage will see a lot of spoil taken away by trucks, so there will be an increase in construction traffic at the site. We will work to coordinate the spoil removal as efficiently as we can and minimise congestion around the worksite. The digging activity will take approximately two months to complete.
Planning is underway for the beginning of a new wastewater pipeline on Montrose Terrace which will help improve the flow of wastewater from the area into the new pump station. Work on the pipeline is due to commence in May and will take three months to complete. A one-way traffic system will be in place from Montrose Terrace to the beach and Sidmouth Street.
Thank you for your patience and understanding while the piling and concrete pouring was underway - it has been a busy and noisy time for the project. We will update you again when we have more news and photographs of our progress. For the latest on our progress, check out the video.

A construction timeline for our Mairangi Bay project

Why is it needed?

Sidmouth Street Pump Station receives wastewater from properties between Long Bay and Castor Bay and pumps it via East Coast Road to the Rosedale Wastewater Treatment Plant for treatment. Due to an increase in population and wastewater, the current wastewater pump station is struggling to cope, particularly during heavy rainfall when diluted wastewater can overflow up to 10 times per year, approximately 70 metres out to sea at engineered points on either end of Mairangi Bay.
In 2014, we began a project to look at the best option for a replacement pump station and to work with Auckland Council to integrate planning with the reserve management plan at Mairangi Bay. In 2015, we presented a concept to the public for a replacement pump station. Since then, we have been looking at the best way to integrate the pump station design with the reserve surroundings while minimising environmental impact.

Traffic management

The current road closure will remain in place until we can complete the majority of the underground shaft. When the digging of the shaft doesn’t require as much space, we will change the traffic to a one-way traffic system around the beach side from Sidmouth Street to Montrose Terrace. This will allow us to undertake the pipeline construction on Montrose Terrace. We will inform you once timing of this change is confirmed.

What are the benefits?

The new pump station will include larger pumps and technology to cope with wet weather flows, virtually eliminating overflows. The benefits include:

  • Reduced wastewater overflows and improved beach water quality
  • Cater for population growth in the area
  • Improved open space and integration with the reserve
  • New building architecturally designed to improve the visual appearance of the reserve 
  • New technology to manage and treat odour helping to reduce the total site footprint

Any questions?

If you have any questions about this project please email: [email protected]

Newsletters and more information

Newsletter 2 project update May 2021
Newsletter 1 project overview April 2021
Media release August 2020