The NZ Transport Agency is advising motorists to plan ahead and allow extra time for their journey as it makes further progress in raising and widening the causeway along the Northwestern Motorway (SH16).
Overnight works to connect the newly constructed southern section of the Whau River Bridge, which forms part of SH16, to the existing structure will be carried out between 7pm Saturday 19 September to 10am Sunday 20 September, weather permitting.
This is called a bridge “stitch” and involves pouring concrete to connect the two structures.
The concrete will take about 12 hours to gain sufficient strength. Vibrations from passing traffic can affect this process so two of the three westbound lanes will be closed overnight between Patiki Road on-ramp and the Te Atatu Road westbound exit.
One lane westbound will remain open throughout. This is because the lanes over the bridge are temporarily reconfigured and one lane runs on the northern side of the bridge. These overnight closures mean that drivers will be unable to enter the motorway using the Patiki Road westbound on-ramp or exit the motorway westbound at Te Atatu Road.
The Causeway Alliance is raising and widening 4.8km of SH16, from Great North Road to the Whau River Bridge just before Te Atatu. The Causeway Upgrade is one of six projects either completed or under construction to link the Northwestern and Southwestern (SH20) motorways, known as the Western Ring Route, providing a motorway alternative to SH1.
Detours will be in place. For more information visit www.nzta.govt.nz(external link).