The upgrade’s centrepiece is an additional Biological Nutrient Removal (BNR) facility, which will be situated to the south of the existing operations. The project also includes the construction of a new road linking Ascot Road and Puketutu Island, and an embankment that will shield the plant’s neighbours from the new facility and ultimately provide a pathway between the Watercare Coastal Walkway and the Greenwood Road Park.
Project Manager Sven Harlos says the new road will ensure continued safe public access to Puketutu Island.
“Island Road presently runs between the existing plant and the new facility. The new road will go around our site, which is safer and more convenient for the community and for us, and fits in with the work we are doing to restore Puketutu Island,” he says.
The new BNR facility uses the same technology currently employed at the Mangere plant to remove nitrogen and phosphorus from the wastewater stream. Common sources of these nutrients include farm run-off, industrial discharges, stormwater run-off, and human and animal waste.
Their presence in waterways can lower oxygen levels, in turn reducing water quality and environmental diversity, and harming marine life.
Sven says the new facility, combined with planned upgrades elsewhere in the network that will allow wastewater streams currently treated at Mangere to be diverted to Rosedale, will ensure Watercare continues to meet the expected demand for its services in an environmentally sustainable fashion.
For more details, see the BNR facility newsletter