The first of two additional overhead gantries has been installed on the state highway between Porirua and Tawa.

Originally two nights of work had been planned, for health and safety reasons, work was postponed on the first night due to the windy conditions. All remaining work to complete this gantry will happen under lane closures.

Intelligent transport systems

New technology and signage is being installed along SH1 between Porirua and Tawa to help people navigate the roads more easily and keep them informed of any incidents or crashes on the road ahead. This includes new electronic signage to advise of incidents or estimated journey times, and new CCTV to ensure that the motorway is operating safely and efficiently.

While most of the work generally won’t disrupt motorists, there will be some parts of the project that require overnight road closures or diversions.

Additional CCTV and electronic signage is being installed on other parts of SH59 and SH58 to help make for better journeys.

Above left: VMS sign on SH1 south of Porirua. Above right: Gantry installation on SH1 north of Johnsonville, during an overnight closure in January 2022.

Work on the go

Our current focus is on installing additional managed motorway technology and infrastructure along State Highway 1, southbound between Porirua and Tawa, to help people navigate the roads more easily and keep them informed of any incidents or crashes on the road ahead. 

  • Preliminary work to prepare the area (trenching work and installation of power to where the gantries will go) is complete. 
  • Work to finish the foundations and barrier systems for one overhead gantry, the steel beam which holds the large electronic signs, is ongoing.

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Improving interchanges

Waka Kotahi has made changes to signage and road markings to improve safety and efficiency and to help road users when getting on and off State Highway 1 (SH1).

This is part of work we are doing throughout the Wellington region to help improve safety and efficiency of the wider network, and to ensure drivers are aware of how they can help ensure the network is flowing smoothly.

SH1 Tawa southbound off-ramp We have modified the off-ramp merge road markings and installed new signage to improve visibility. Safety improvement work included lane edge lines, lane speed limit markings, hatching on the shoulder and lane divisions, shoulder hatching to and through the underpass, relocating traffic signs and installing a speed indicator device.
SH1 Tawa, SH1 Churton Park and SH1 Newlands southbound on-ramps We modified the on-ramp merge road markings, added a directional arrow, and installed signage to improve merging (for all three on-ramps).
SH1 Johnsonville northbound off-ramp We have extended the off-ramp lane markings to separate the Johnsonville off-ramp and SH1 traffic earlier in order to improve the safety and efficiency of motorway.

In addition to this work at the intersections, signs have been replaced or installed on all ramp approaches in both directions.

Glossary of lines and signs

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Painted arrows on road. Within a gore area these remind motorists to merge in either direction.

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Continuity lines

Used to indicate the edge of the through carriageway where it is intended the line be crossed by traffic entering or exiting the highway.

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Flush island marking

These are white diagonal lines, painted down the centre of highways, marking an area about one-car-width-wide. They are called ‘flush’ because they are not raised.

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The marked space between a highway and on/off ramps that merge into it.

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Shoulder hatching

White diagonal lines painted onto the shoulders of roads, to mark more clearly where the road ends.

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Speed limit indicator device

Digital signs on the side of the road indicating the speed of each vehicle that travels past it.

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Speed limit roundels

Speed limit road marking indicating the point which the speed limit begins.