Tree protection key in pump station upgrade

20/10/2023
Lawson Cypress tree
Great care is being taken to protect the roots of a Lawson Cypress tree as part of our upgrade of the Glendowie Wastewater Pump Station.

Excavating the tree’s roots is essential for allowing sufficient space to strengthen the pump station’s foundations, making it more resilient to earthquakes.

To clear out the dirt, contractors have used an air spade with support from a consultant arborist to loosen the soil around the tree's root system.

Lawson Cypress tree root

Exposing the root system using compressed air will enable the arborist to safely locate the roots to keep them outside the construction zone and away from machinery that could damage them.

Project manager Tom Lyne says the air spading work is important as the wastewater pump station encroaches on a tree root zone in Maybury Reserve.

"Exposing the tree roots using air spading allows for the roots to be easily located and identified without compromising the health of the tree.

“Doing this work will allow us to strengthen the building's foundations to support the weight of steel reinforcing, concrete and extra fastenings used to increase the seismic rating of the building.

“The seismic works at Glendowie Wastewater Pump Station are part of a $6.5 million package to improve the resilience of 15 critical water and wastewater assets around Auckland in the event of earthquakes and other natural disasters like floods and fires.”

The seismic works are one of the many projects we are undertaking as part of a broader $18.5 billion programme to build, renew and upgrade water and wastewater infrastructure over the next 20 years.

Lyne says most of the work has focused on replacing the external brick walls with more resilient steel-reinforced concrete.

"The external walls are then fixed to the internal brick walls using steel fasteners to improve the stability of the entire structure.

"We've also used this programme of work as an opportunity to replace roofs and the external brick work to make sites safer.”

Lyne says completing the seismic upgrades at Glendowie Wastewater Pump Station is on track to be completed by mid-November and will mark the end of the planned seismic works for this financial year.

“Despite some challenges, mainly caused by the weather, the seismic works have gone smoothly.

“I am incredibly proud of the work and effort our teams and contract partners have put in to improve the resilience of these assets.”