Petone to Grenada Link Road one step closer as preferred route confirmed


The Wellington region is one step closer to reaping the economic, safety and journey time benefits of the Petone to Grenada Link Road, with the NZ Transport Agency today confirming the preferred route.

The proposed project is part of a suite of new roading, cycling and public transport projects being progressed on behalf of the Government throughout the Wellington region to improve economic growth, road safety, and make it easier and less time consuming for people to get around.  The project, estimated at $250-270m, is supported by all councils in the Wellington region, and ranked as the region’s third highest transport priority.

Transport Agency Regional Director Central Raewyn Bleakley says the preferred route has been determined following extensive analysis and community consultation. Much of this focused on the three options being considered for the ‘north of Tawa’ section, two of which required significant amounts of property. 

Ms Bleakley says the Transport Agency has decided to focus on managing future traffic growth within the existing corridor, with the option of putting in place a ‘managed motorway’ (similar to the smart motorway currently being built south of Ngauranga), or a similar approach, should traffic growth require it.  Only minor designation changes will be required and property impacts will be minimal.

This means that the other two options – a road through Takapu Valley, or taking property to widen the motorway north of Tawa to six lanes – will not be required as part of the proposed project.

“Over the last year and a half, we have been undertaking rigorous investigations, while working with the public and councils to make sure we understood what was important to the region.  This work has helped us to identify how we can best harness the remarkable benefits of this project while minimising its effects.

“Having examined the evidence, we are confident that we can manage future traffic growth within the existing corridor north of Tawa through a ‘managed motorway’ approach if required in the future, and by utilising the shoulders of the existing road.”

Ms Bleakley says the benefits of the project are substantial, saving motorists as much as 30 minutes a day for return trips.

“Once built, the Petone to Grenada Link Road will transform journeys and bring the region’s communities and economic centres much closer together.”

Paul Swain, Chair of the Regional Transport Committee, welcomed today’s announcement. “It’s great to have some certainty around the route.

"The new road will improve connections between the region’s east and west for everyone – people in cars, people moving freight and public transport users.  It creates the potential for a direct public transport link between Porirua and Petone.

“And having an alternative route in and out of Wellington City will significantly boost Wellington’s resilience in both small events like temporary blockages of the state highways and major natural disasters like earthquakes or floods.”

Ms Bleakley says the Transport Agency was grateful to the large numbers of people and stakeholders who provided input into the Transport Agency’s proposals.

“We appreciate that this has been a challenging and sometimes contentious process, and we have been listening to community feedback throughout.  The preferred route reflects our commitment to keep an open mind and make robust decisions, and our decision has come from careful analysis and balancing the range of factors we are required to consider".

Ms Bleakley says the Transport Agency listened closely to the evidence of its technical experts and the views of landowners, councils, the community and other stakeholders.   A number of adjustments were made to the Transport Agency’s earlier proposals, to address a range of issues raised throughout the investigation and consultation process, and have helped shape the location and extent of the final route.

“This is a project that will dramatically change to day-to-day travel. It will also have numerous flow on benefits, such as keeping Wellington better connected when severe natural events occur, and making the region a more attractive place to live and do business by improving journeys between Wellington, Porirua and the Hutt Valley.”

The project will join other regional transport initiatives like the Wellington Northern Corridor, the Wellington to Hutt Valley Walkway, Cycleway and Resilience project, and Bus Rapid Transit as projects that will improve transport in Wellington for future generations, delivering on the Government’s goals of economic growth, safety and improving travel choice.

Ms Bleakley says that now that there is a confirmed route, the next steps will be to prepare the necessary documents to apply for Resource Management Act (RMA) consents next year, with a view to starting construction in 2019.

The project will be designed to dovetail with proposals for the Wellington to Hutt Valley Walkway, Cycleway, and Resilience project, although the two projects do not rely on each other to progress.  Designs for the Petone interchange will place a high priority on being cyclist-friendly, while also freeing up a key bottleneck on State Highway 2.

Ms Bleakley says as part of the work ahead, the Transport Agency will also consider potential safety improvements at the Tawa Curves on State Highway 1.  Further information on this will be available at a later stage following further investigation.

The proposed route will:

  • Provide a four-lane route between Petone and Tawa plus extra crawler lanes on the Petone side
  • Run between Petone and Tawa via the Horokiwi Crest (largely avoiding homes in the Hunters Hill area)
  • Be constructed mostly in cut through Horokiwi to reduce visibility from  Horokiwi and much of the Hutt Valley.
  • Create four new interchanges, providing better access on and off State Highway 1 and 2
  • Avoid impacting on the Belmont Regional Park,
  • Provide future highway capacity north of Tawa within the existing highway footprint between Tawa and Transmission Gully when it is needed.

The benefits of the Petone to Grenada Link Road for the Wellington Region include:-

  • Keeping the Hutt Valley better connected in an earthquake, slip or crash
  • Creation of several hundred brand new jobs and facilitating growth in areas like Lincolnshire Farm, Porirua & Seaview
  • Saving every commuter between Porirua and the Hutt Valley around 30 minutes [return journey] per day in peak travel
  • A new interchange at Petone, a key bottleneck, making journeys smoother and faster along SH2 and the Esplanade
  • Providing better connections for communities such as Grenada North and facilitating improved connections & access to Belmont Regional Park
  • Fill from the construction of the Link Road could be used to build the cycleway between Petone and Wellington or for other construction activities nearby.

Q & A

How will we manage any future increased traffic demand on SH1?

We are exploring options to implement a ‘managed motorway’ which would work much like the Smart Motorway, which will open on the Wellington Urban Motorway next year between Thorndon and Johnsonville. This is an internationally proven concept that focuses on optimising traffic flow through speed limits and lane controls.

We can also increase traffic capacity within the existing motorway footprint by utilising the existing shoulders.  We will be examining the performance of the Wellington state highway network in the coming years to investigate where managed motorways could optimise traffic flow.

What were the options for the north of Tawa section?

The Transport Agency was previously considering three options with regard to projected traffic growth north of Tawa – widening the motorway north of Tawa to six lanes building a two lane link road through Takapu Valley (both of which would have required significant property acquisition), or to retain the existing corridor and monitor future traffic growth (with minimal property impacts).

We have proceeded with the third option approach, with a potential managed motorway approach to be pursued to help future proof against traffic capacity constraints. This involves minimal property impacts. A managed motorway will only be implemented when it is required.

What work was this decision based on?

The Transport Agency is committed to ensuring all major transport decisions are made with expert technical advice, extensive community and stakeholder involvement, and a robust evidence-based approach. The process to determine a preferred route has been significant, including advice from a range of technical experts, briefings, workshops and presentations, landowner meetings, thorough examination of all potential options, extensive transport modelling and investigation work, and consideration of environmental and property impacts, along with land use development and transport resilience matters.

Will you be using fill (dirt from earthworks) to reclaim the harbourside?

Where possible the Transport Agency will look to align construction of the Cycleway, Walkway, and Resilience project with the Link Road. This could include making use of fill to help reduce the costs of this project’s preferred option between Petone and Ngauranga. However, while this would be an added benefit from dovetailing the projects, the cycleway is not dependent on the Petone to Grenada Link Road in order to progress.

What next – and when will I get another chance to have a say?

Work to prepare RMA consents is likely to continue through to late next year.  Part of this work will be to prepare an Assessment of Environment Effects and consider how to mitigate any of the adverse effects of the Link Road on the environment and people living in the area. 

The public will get another opportunity to provide input on the initial design of the preferred Link Road route and suggest ways in which we can limit things such as construction impacts, noise and urban design and so on.

At this stage, the Transport Agency expects to lodge its consent applications in late 2016. Construction of the Petone to Grenada Link Road, assuming consent is granted, is scheduled to begin in 2019.