Coast Clear for Wellington: Seaview Wastewater Treatment Plant
Preserving the marine ecosystem
In the 1990s, Hutt City Council saw a need to improve and protect the region’s marine and coastal environs. The existing Wainuiomata Wastewater Treatment plant needed to be replaced, and Wainuiomata Valley’s wastewater redirected to a new plant through a pipeline connecting the two valleys.
The new plant needed to meet stringent effluent quality requirements to cleanse Wellington’s southern coast and reduce discharge to Wainuiomata River.
A design-build solution
In 1999, Hutt Valley Water Services – a subsidiary of SUEZ and OMI Beca – was awarded the contract to design, build, operate and maintain the new Seaview Wastewater Treatment Plant (WTP) for 20 years.
The team cultivated a deep understanding of the client’s needs before developing a range of smart solutions targeted at improving the coastal environment while minimising the plant’s impact on the local population. Integral to the plant is a thermal drying facility that treats and dries wastewater sludge into a pathogen-free pelletised product for horticultural use. A range of odour control features ensure a safe, healthy environment for workers and the community.
Commissioned in 2002, the plant can treat up to 53 million litres daily, servicing around 146,000 residents and a large number of local industries.
Ready for anything
The wastewater tanks developed for the plant are designed to remain intact during an earthquake, reducing the chance of wastewater spilling into the harbour and minimising operational disruptions.
With flexibility to upgrade the plant’s capacity by up to 50 per cent, the Seaview WTP is well prepared to handle future population growth.