Key Takeaways
- The Onehunga water treatment plant is currently in the detailed design phase of an upgrade to meet New Zealand drinking water standards
- A new ultraviolet disinfection system will be added to provide an additional barrier against microbiological contaminants
- Regular monitoring for PFAS is not required nationwide, and Watercare does not do routine testing
- New Zealand has not reduced the thresholds at which PFAS are considered safe, unlike other countries
- Auckland’s water supply is currently in a "strong position" with full dams and maximized production at the Ardmore and Huia water treatment plants
Introduction to the Upgrade
The Onehunga water treatment plant is undergoing a significant upgrade to ensure it can consistently meet New Zealand drinking water standards. According to Sharon Danks, the head of water, the plant is currently in the detailed design phase of the upgrade. This phase is crucial in ensuring that the treatment plant can provide safe and clean drinking water to the community. As part of the upgrade, a new ultraviolet disinfection system will be added to provide an additional barrier against microbiological contaminants. This system will help to further purify the water and reduce the risk of waterborne diseases.
PFAS Monitoring and Testing
Despite the upgrade, there are still concerns about the presence of PFAS (per- and polyfluoroalkyl substances) in the water supply. PFAS are a group of chemicals that were invented in the 1930s and have been used in various applications, including in the US atomic-bomb-making Manhattan Project. These chemicals have an almost indestructible carbon-fluorine bond and are now known to be harmful to human health. However, nationwide, the rules do not require regular monitoring for PFAS, and Watercare does not do routine testing. According to Danks, Watercare continues to look at global trends and learnings from PFAS monitoring and testing, but it does not currently have a regular testing program in place.
Global Trends and Concerns
The issue of PFAS is not unique to New Zealand, and many countries are grappling with the problem of PFAS contamination. In the United States and Europe, there have been lawsuits and clean-ups related to PFAS contamination. Some countries have also reduced the thresholds at which PFAS are considered safe, but New Zealand has not followed suit. The lack of regular monitoring and testing for PFAS in New Zealand is a concern, especially given the potential health risks associated with these chemicals. The fact that tests at Onehunga in 2023 and last year found low levels of PFAS that had closed the plant in 2022 highlights the need for more regular monitoring and testing.
Auckland’s Water Supply
Despite the concerns about PFAS, Auckland’s water supply is currently in a "strong position", according to Danks. The city’s water supply comes from the metropolitan water network, and the agency has been able to maximize production at the Ardmore and Huia water treatment plants. In summer 2023, the agency activated its consent to take more water from the Waikato River to make up for the 18 million liters a day lost at Onehunga. However, with the upgrade of the Onehunga plant and the maximized production at other plants, Auckland’s water supply is well-positioned to meet the demands of the city. The fact that the second Waikato treatment plant is offline and not needed to supplement supply is also a positive sign, indicating that the city’s water supply is currently stable.
Conclusion
In conclusion, the upgrade of the Onehunga water treatment plant is an important step in ensuring that the community has access to safe and clean drinking water. The addition of a new ultraviolet disinfection system will provide an additional barrier against microbiological contaminants, and the detailed design phase will ensure that the plant can consistently meet New Zealand drinking water standards. However, the lack of regular monitoring and testing for PFAS is a concern, and it is essential that Watercare and the government take a more proactive approach to addressing this issue. With Auckland’s water supply currently in a "strong position", it is essential that the city continues to invest in its water infrastructure to ensure that it can meet the demands of a growing population.