PUKEKOHE WASTEWATER TREATMENT PLANT
doubles in size
Pukekohe may be famous for car racing and horticulture, but it also has one of the most sophisticated wastewater treatment plants in New Zealand to protect the environment?
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onstruction (phase one) of Watercare’s $110 million project began in December 2018 when a new treatment plant was built alongside the existing Parker Lane facility. By September 2021, phase two was underway, with existing batch reactors being converted to activated sludge tanks. The most significant feature of the entire project, which caters for the booming local population, is an advanced membrane bioreactor process with ultraviolet disinfection. This will see a major improvement to the discharge water quality into Parker Lane stream, which leads to the Waikato River. Watercare project manager, Sven Harlos said the work under the banner ‘building better not bigger’ would mark a new chapter in the plant’s history. “Back in the 1960’s and up to as recently as 2009, Pukekohe’s wastewater was treated via oxidation ponds – a basic form of treatment,” Mr Harlos explained. “Since amalgamation in 2010, Watercare has put considerable effort into investing in wastewater infrastructure in Franklin. The plant upgrades will mean fewer wet-weather overflows and improve the capacity of the 60 — Design and Build Franklin — 2021-2022
wastewater network. It will also result in a significant improvement to the discharge water quality into the local Parker Lane stream and the Waikato River.” The plant treats wastewater from Pukekohe, Buckland, Tuakau, Pokeno and Patumahoe. On completion in May 2022, the plant will go from treating flows from 30,000 residents to 60,000 residents. Major improvements to the Buckland trunk sewer system, including a new pump station and pipework have also taken place. At its peak, 150 construction staff were on site, making it one of Pukekohe’s largest infrastructure projects in recent years. There were still 30-40 construction workers on site in September 2021 to efficiently convert the existing sequencing batch reactors into activated sludge reactors. At that time, the project had reached the final round of Engineering New Zealand’s 2021 ENVI awards and the Institute of Public Works Engineering Australasia (IPWEA) awards. The winners of the IPWEA competition were to be announced early 2022. One of the most significant achievements took place however many years before when
Watercare successfully collaborated with Iwi to achieve a 35-year, uncontested resource consent. Nine marae came together as a single entity, Te Taniwha o Waikato, to take part in negotiations. A Cultural Impact Assessment was made and as a result, the plant design was modified so that water clarity as well as the level of pathogens and background bacteria in discharged water was better than the river quality itself. There are on-going korero about ways to ensure the health of the river, with twice-yearly workshops, as well as regular monitoring. Watercare Poutiaki Tikanga Maori (Principal Advisor) Richie Waiwai says the organisation is striving for better infrastructure through authentic engagement: “For Maori, an awa (water body) is regarded as an ancestor. The river represents the mana and mauri (life force) of the people, and is central to tribal identity, and their spiritual and physical wellbeing.” It’s hoped the public will have a chance to view the Pukekohe Wastewater Treatment Plant in 2022 (depending on Covid alert level restrictions).
