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.
Click here to see a map of the proposed route.
How will it be constructed?
Hunua 4 will be 1.6 and 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?
Detailed design of the pipeline has been completed. Where possible, the pipeline design and the construction technique have been tailored, based on local site conditions in order to minimise cost and distruption to the local community.
The construction contract has been awarded and construction starts in May 2012.
Detailed design of the pipeline has been completed. Where possible, the pipeline design and the construction technique have been tailored, 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 (plan attached).
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:
Thomas Road, Flat Bush: a 225m length of Hunua 4 was installed within road carriageway.
SH20 Manukau Harbour Bridge and approaches in Mangere Bridge and Onehunga: a 1.9km length of Hunua 4 was installed as part of construction of the new motorway bridge and on adjacent roads including railway crossings
Princes Street, Onehunga: A section of Hunua 4 was installed across Onehunga Branch Railway Line during the 48 hour track closure.
Mt Smart Road, Onehunga: A cross connection between the existing Hunua 3 watermain and a section of Hunua 4 was installed along Mt Smart Road and Victoria Street.
Puhinui Station, Papatoetoe : 150m length of Hunua 4 was installed across the North Island Main Trunk railway line as part of construction of the KiwiRail footbridge replacement.
What is the timeline?
Construction will take place from May 2012 to 2016. Construction will generally take place from south to north, as follows: