FAQs

Preferred alignment

1. What are the benefits of the Petone to Grenada Link Road for the Wellington Region?

Beneifts of the new transport route 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.

2. 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.

3. 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.

4. 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.

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

Where possible the Transport Agency will look to align construction of the Wellington to Hutt Valley Walkway, Cycleway 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.

6. What next – and 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.

Previous questions (February 2015)

1. What is involved in the siting of the interchange structures in Petone? 

The interchange structures will be located to keep them outside the Wellington Fault Zone, and away from areas subject to liquefaction and lateral spreading.  Where this is not possible, the structures will be designed to withstand liquefaction hazards.

2. Have plans been designed knowing the results of the geological investigations already?

The existing alignments have been developed to locate the interchange away from the known location of the Wellington Fault zone.  The geotechnical investigations into the Wellington Fault zone are ongoing, and we will further refine the project layout as necessary as more information becomes available.  Similarly based on the liquefaction risk assessed from the geotechnical investigations, the design for the interchange will be developed to achieve resilience.

3. Where is the 'fault zone area' used in the Transport Agency's interchange site placement investigation?

The following plan shows the location of the interchange in relation to the fault zone.

4. Is the Link Road compatible with future regional road plans?

The proposed P2G route will improve resilience in combination with the Transmission Gully scheme to the north, and enable access to be more quickly restored to the Hutt Valley in the event of major earthquakes.  In conjunction with a potential Cross-Valley Link, it will improve resilience to access to the eastern areas of Hutt valley including Seaview and Wainuiomata.

The proposed route will also complement improvements on SH2 and SH58, including the new SH2/SH58 Haywards Interchange, for which construction is underway.

5. Can you provide stats on the estimated numbers of Hutt Valley vehicles that will access Transmission Gully via SH58 once it is completed?

2031 flows indicate that on an average weekday 3,200 vehicles would travel eastbound and 3,700 would travel westbound, to and from the Hutt region respectively, to access TG if P2G is not constructed.  If P2G is constructed this number reduces to 2,300 vehicles eastbound towards, and 2,200 vehicles westbound from, the Hutt region to access TG.

6. How will stats for vehicle usage of P2G change once TG is operational?

TG is programmed for construction completion before P2G, so the opening of TG will not affect P2G.

7. How will people travelling along the Esplanade access SH2 to head north from the proposed Petone interchange?

The current thinking would require vehicles to travel through two signalised intersections and then turn right at a third signalised intersection onto a northbound on-ramp to SH2 (refer to below sketch of proposed Petone interchange).

View larger size

8. Is the current design of the Petone interchange focused more on moving traffic west over P2G route?

The current thinking has traffic from the Esplanade and traffic from P2G having similar priority. Both the Esplanade and P2G approaches to the interchange have a free left turn, two ahead lanes and a single right turn lane. The left turn lanes (to Wellington from the Esplanade and to Lower Hutt from P2G) will receive the highest priority in order to accommodate the volumes of traffic, although signal timings can be adapted as vehicle flows change.

9. How and where will the Cross Valley Link connect with SH2?

We have carried out an investigation on behalf of Hutt City Council into links with Seaview, colloquially referred to as the Cross Valley Link. This work has identified options for improving capacity between SH2 and Seaview. The main options involve either an upgrade of the Esplanade, a connection via Wakefield Street/Whites Line or using the railway corridor to the south of Wakefield Street.

10. What is the expected construction timeframe for Cross Valley Link?

Hutt City Council has included a Cross Valley Link in the 2015-2018 RLTP.

11. Does this latest modelling include demand for public transport?

Greater Wellington Regional Council’s transport models, both the Wellington Transport Strategy Model (WTSM) and the Wellington Public Transport Model (WPTM) have been used to assess the demand for public transport, in conjunction with the P2G project.

12. What public transport routes would use P2G? 

At this time no new specific bus routes have been identified, but modelling indicates that there would be demand for public transport services using the P2G route.  The modelling undertaken to date has included potential new bus routes between Johnsonville and Lower Hutt CBD (via Lincolnshire Farms), Lincolnshire Farms to Lower Hutt & Johnsonville and Waterloo and Porirua (via P2G). In practice, decisions would be made nearer the time with GWRC specifying new routes for the operation of new bus services.

15. Can you provide any more information on any potential traffic effects now Petone West is attracting big box retail stores?

The traffic effects of Plan Change 29 (Proposed zoning change to the western end of Petone - Petone Mixed Use) were covered in that application. Changes in transport demands from the plan change are not included in the current regional strategic model (WTSM 2011). However, they will be included in the next WTSM model update.

17. Will there be effects into Petone West and the surrounding side streets that are not covered by P2G area e.g. traffic backed up down side streets?

As the project progresses we will update the micro-simulation modelling at this location to take into account the latest information from the strategic model.

18. What is the current number of freight vehicles using the Esplanade?

Currently, there are approximately 24,000 vehicles per day travelling along the Esplanade.  Of these 2,600 (11%) are heavy commercial vehicles.

20. Will P2G have a cycle path?

Our initial work has indicated that there is likely to be demand for cycle facilities along P2G.  As part of the next phase of works we will work to determine what provision for cycling we can include in the scheme design.

21. How many roundabouts are proposed for the north end of Tawa? 

The current thinking has two roundabouts on the east side of SH1 with the closest existing roundabout west of SH1 converted to a traffic signal controlled intersection.  We will continue to consider the design of the proposed Tawa interchange as the project progresses.

22. How often have predictions for traffic/population growth changed over the period of these motorway studies?

The Regional Council’s transport models use census data and estimates of future population and employment to generate predictions about future travel patterns.  The model is updated on a five-yearly cycle.  It was updated in 2006 and again in 2011 and is presently being updated to incorporate 2013 Census information. This information has also been used to review inputs to the models for application to the P2G project. Over the course of the Petone to Grenada project, the model has been updated once.

23. When were Iwi last updated?  

A number of meetings have been held with different iwi groups over the past 12 to 18 months. Our agreement with Iwi is that we will update them on any changes to what we are proposing.

24. What effects will there be on Honiana Te Puni and the foreshore?

Our design avoids the Honiana Te Puni reserve, please see the interchange layout for Petone.

25. Have all groups, like Korokoro Environmental Group (KEG), had their concerns about damage to the Korokoro Valley answered?

Groups that are interested in the Korokoro Valley have been contacted and update meetings were last provided at the end of 2014. The groups we met with are the Friends of the Belmont Regional Park, KEG, and the Horokiwi Community Group. All questions were answered and information provided as far as possible for this stage of the project.

26. What route is planned to provide access/ walking into the Korokoro stream area from the Petone beach?

We are yet to confirm an access route into the Korokoro area. However, our investigation includes considering potential new links between the Petone foreshore and Belmont Regional Park. Potential connection options will be developed further as part of the Scheme Design during 2016.

27. How is Hutt City Council’s (HCC) population growth statistics reflected in the Transport Agency’s traffic use predictions?

The Wellington Transport Strategic Model, operated and maintained by Greater Wellington Regional Council, is the model on which all traffic modelling for the Petone to Grenada Link Road has been based.  This includes information about expected future population growth.

28. Why were the project objectives for the Link Road changed?

The initial project objectives were broad and pre-dated current policies and strategies. They were refined to more specifically capture the economic and transport-related benefits (and other matters) that the Transport Agency is seeking to achieve through the project.

29. Is it normal for project objectives to be changed during the lifecycle of a project?

Project objectives are typically revised throughout the life of a project as it evolves.  This ensures the objectives remain appropriate during the various stages of a project and are consistent with any policies or strategies that they may need to adhere to.

30. Have the project objectives just been refined to support NZTA’s selection of a preferred option/route?

No, the updated project objectives are about ensuring the project meets specific outcomes and are more specific and relevant to what we wish to achieve.