Watercare is constructing a new watermain to cater for population growth and to increase the security of the water supply to the Auckland region.
The Hunua No. 4 Watermain (Hunua 4) will run for 28 kilometres from Redoubt North Reservoir in Manukau Heights to Campbell Crescent in Epsom, connecting to the local water supply network along the way. Ultimately the Hunua 4 will extend through to Khyber Reservoirs in the central city.
How will it be constructed?
Hunua 4 will be 1.3 to 1.9 metres in diameter. It will mostly be laid under the road, though in some places it will cross streams, private property and rural land. Watercare is liaising with these private property owners.
For the majority of the route, open trenching methods will be used to lay the watermain. In sensitive areas – such as busy intersections – more specialised construction methods will be used, eg.tunnelling or pipe bridges.
Traffic around the construction site will be carefully managed to minimise disruption to motorists.
What is happening now?
Watercare is currently developing the detailed design for the pipeline. This includes tailoring the pipeline design and construction technique based on local site conditions in order to minimise cost and disruption to the local community.
What has been achieved already?
Land use designation and resource consents for the project have been granted by the Auckland Council for the route from the Redoubt North Reservoir in Manukau Heights to Campbell Road in the suburb of One Tree Hill.
Packages of advanced works have been undertaken in association with or ahead of other planned infrastructure works. The early installation of Hunua 4 in these locations reduces the overall disruption to the community and has enabled practical, cost effective integration of construction resources and personnel.
ABOVE RIGHT: Hunua 4 Project Manager Andy Spittal and Project Engineer Sharon Danks review plans for the section of Hunua 4 that runs under the Manukau Harbour Bridge.
Advance work completed to date:
ABOVE RIGHT: A 225m length of Hunua 4 is installed along Thomas Road in Flat Bush.
What is the timeline?
Now to mid 2011
NIMT rail crossing advanced works package proposed
Nov 2011 – Mar 2012
Appointment of main contractor
Main construction phase
Mid 2012 to 2016