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State Highway 58 Safety Improvements


On 16 November, PRA had a further meeting with Waka Kotahi and representatives of Waka Kotahi and Porirua City Council to get an update on the plans for the next stages of the SH58 safety improvements.  Operation of the school buses continues to be an area of concern.  Waka Kotahi gave a presentation at the meeting and our notes are here.

On 21 September, PRA met with representatives of Waka Kotahi and Porirua City Council to present the concerns being expressed by residents with regard to the proposed SH58 safety improvements.  There were particular concerns over the failure of the plans to address the operation of the school buses.

Notes from this meeting are here.


On Friday 26 August 2022, PRA received an update from Waka Kotahi on the SH58 Safety Upgrade.


The update began by thanking the Residents Association and community members for engaging with them at the meeting last week.  They acknowledged that they were not fully prepared with all of the relevant detail on topics that are important to us, and were not able to show how past feedback had been considered. They have now reviewed their previous engagement materials and reports and followed up on the issues raised with the design team. 


The following responses were provided on key subjects, setting out where they are at currently with the project designs. It was noted that there are some key areas in these diagrams where they would like to work further on with relevant people from the community – particularly regarding the final details of the bus stops.


The designs will allow for a passing lane Eastbound from Moonshine Road to Harris Road 

Waka Kotahi are proposing to accelerate the section of work from Harris Road to Moonshine Road, by securing early property acquisition and consents for this piece of work. They are bringing it forward because it is straightforward in comparison to the two roundabouts and means they can keep working on making the overall corridor safer.  

The existing passing lane is currently closed, however when the project is completed, this section will include two uphill lanes. These will either operate as a regular lane on the left and a passing lane on the right, or as slow vehicle lane on the left and a regular lane on the right – with either approach meaning that cars will have space to overtake heavy vehicles moving more slowly up the hill.  

The total length of the passing lane when the project is complete will be 720m.  This is a reduction in length of 250m from the previous passing lane, to allow safe completion of passing movements well before Harris Road. This will ensure that there is safe access to Harris Road, and that turning vehicles are not in danger from faster vehicles overtaking slower vehicles uphill. 

Widths in other places for passing (e.g. breakdowns) 

Once the project is completed, the road width between the edge barrier and the median barrier will be at least 5.45m, made up of a 1.2m shoulder, a 3.5m vehicle lane, and 0.75m median barrier space. Large heavy vehicles have a maximum width of 2.55m, meaning that it will be possible for other vehicles to pass a broken-down truck pulled over to the side of the road, in case of a breakdown occurring outside the uphill passing lane.  

Similarly, this width will allow emergency services to pass when other road users pull over to the side.   


Bus stops 


The project includes a large bus turn around area at the Flightys/Murphys Road intersection in line with what was shown at the presentation given on 16 August 2022. This has been designed so that buses can access the area from both directions using the roundabout and Murphys Road and also provides space for light vehicles to park whilst dropping off or picking up.  

Bus stops have been included at the Moonshine Road intersection at the current stage of design, on the approaches to the roundabout in both directions. There will also be a waiting/parking area on Moonshine Road which was not shown on the presentation.  


The latest designs for the roundabouts can be found here

Waka Kotahi recognise that feedback at the meeting identified the need for more space in the Moonshine Road area and they want to check that the design will accommodate transfers, pick-ups and drop-offs.  


Roundabout capacity and lanes 


The SH58 safety improvements project has been under development for several years and many iterations of the design have been developed, particularly considering the roundabouts.  


The confirmed design for the roundabouts will be single-lane and have enough capacity for 2,500 vehicles per hour. This compares with a current peak of 1,800 per hour. This will provide sufficient capacity for existing use and some growth.  Roundabouts at these two locations aligns with the purpose of the SH58 project to improve safety at these two intersections.  


Access to Willowbank Quarry 


Right now, a temporary speed limit of 50km/h is in place to manage safety risks from heavy vehicles turning in and out of the Willowbank Quarry.   Waka Kotahi are working with the Quarry to install a right turn bay to improve the safety of this entrance in the short term. 

In the long term and similar to the other side roads along the route, there will be no right-turn access to the quarry as it is located between the two roundabouts and right turning vehicles will be able to u-turn at the roundabouts whether approaching from the west or east.  


The planning and modelling for the roundabouts has taken into account the proposed changes in volumes that the Quarry is anticipating should the current consent application be granted.  Waka Kotahi are working with the Quarry as part of the consenting process to avoid traffic impacts at peak times should there be ongoing operation of the Quarry.


PRA still has concerns over the safety and practicalities of the design that Waka Kotahi are presenting for the next stages of the SH58 Safety upgrade, from Harris Road to the Transmission Gully Motorway.  We are keen to hear the thoughts and concerns of residents and other users of SH58 and can be emailed at

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