Pukekohe Wastewater Treatment Plant expansion flies along


A long, hot summer has been a boon to construction workers as Pukekohe’s Wastewater Treatment Plant doubles in size.
Construction began before Christmas. Stage 1 of the works include new inlet works, a new activated sludge reactor, new membranes, new UV system and new electrical switch rooms and chemical systems. It is well on track to be up and running by December next year.

Project manager Sven Harlos says this is by far Pukekohe’s largest current construction project: “We have about 100 workers on site most days, so it’s pretty busy and we have to be careful we don’t get in the way of the operations team but so far the coordination and cooperation it’s working well.
"Morale is high. Not only is building going well. The builders enjoy the fact that they’re travelling to work against the Auckland traffic and it’s a beautiful spot, in the middle of the countryside, once you get here.”
One of the most innovative features is a new yellow plastic liner for the sludge reactors. Wastewater is highly acidic in its raw form and the liner, which is sourced from Europe, helps prevent the concrete walls from being eaten away: “I know of one of other wastewater treatment plant that used this technology but they had some teething problems, which we learnt from. We’re confident this is going to work really well,” says Rob.   
Electrical and mechanical teams will move in later in the year, as new concrete tanks and switchrooms are ready.
A new bridge has been built over nearby Parker Stream and a recycled bridge from Māngere Wastewater Treatment Plant has also been installed to provide pedestrian access.
Stage 2 of the project will be finished in 2022.