skip to main content

Transmission Gully Presentation to PRA AGM 5 May 2015


Information on Transmission Gully was presented by

    • Lauren McKenzie, Community & Stakeholder Manager, Leighton Contractors
    • Chris Hunt, Construction Manager, Leighton Contractors
    • Reuben Mills, Senior Environmental Advisor, Leighton Contractors
    • David Low, CEO, Wellington Gateway Partnership

Key points included:


  • NZTA awarded Transmission Gully contract to Wellington Gateway Partnership 28 July 2014.
  • It is the first roading public/private partnership (PPP) in NZ.
  • There is a “Design & Construct” 5 year contract
  • Followed by an “Operate & Maintain” 25 year contract
  • Design and construct phase is well underway

 Design & Construct

  • Motorway will be a 28km long open sky’s - meaning all local loads will go under the Motorway.
  • Design resilience is key as the motorway will cross 7 fault zones and 11 different geographical types.
  • Transpower has completed removal of the transmission lines.
  • Other service relocations are being planned including gas and water mains.
  • During design and construction respect for the environment is key.
  • Safety is another driver – there is a financial model for the road which will penalise them if there are accidents on the road.
  • Improved travel times are the other key goal.
  • There is a team of 85 design engineers (mainly based in Auckland) working on the design and development phase. They are at around 40-45% complete with this work.
  • The regulatory requirements are currently being worked through, including demonstrating how they will comply with consent conditions with the Regional Council and territorial authorities.
  • The first priority is to discuss design concepts with the most affected stakeholders/residents. Then conversations are expanded to the wider community.

 Lanes Flat

  • Approximately 70 people are in the Design and Construct planning team currently based on Kenepuru Drive.
  • Once Lanes Flat site is ready these staff will move there. They expect up to 120 people to be based here (in about 18 months’ time) for the 5 year contract.
  • Access to Lanes Flat will be off the Pauatahanui roundabout, with robust traffic management in place.


  • The motorway build will include 540 hectares of ecological plantings. Plant selection and planting design are underway.
  • Plantings will start during 2015 as part of management plans to control sediment going into the Pauatahanui Inlet.
  • Environmental impact induction and training will occur for all those working on the Motorway.
  • Archaeologists will also be working onsite.
  • A Heritage Plan is in place. Reuben gave a number of examples where their services have been utilised, including an Umu site found, Brick Fuel Containment from WWII and the Church.
  • A “Greenroads silver standard” is being aimed for - this is a contractual obligation. “Greenroads” is a collection of sustainability best practices, called "credits," that relate to roadway design and construction. Achieving these credits can earn points toward a total score for the project and in general this Greenroads score can be used as an indicator of sustainability for the roadway.


  • Once works begin, a monthly community update on Leighton’s website is planned. A quarterly newsletter is currently published.
  • The website will be updated once the Transmission Gully Management Plans have been finalised.
  • Augmented reality technology will be utilised to provide more interactive information on the website e.g. to allow you to find a specific property.
  • There is not a lot on the website at this point.
  • The PRA website and distribution list will also be used to send out information.

 Operate & Maintain

  • The David Low, Wellington Gateway Partnership indicated that it is a 30 year contract in total and that the Maintain and Operating components would also be run from Lanes Flat.
  • The Partnership will report monthly to NZTA on the success of community and stakeholder communications.

 Discussion points from Q&A session

The following additional information was given during the open floor question time:

  • Design concept plans have to be consulted with immediate stakeholders first, then rolled out wider.
  • Expect increase in light vehicles in the Village, with staff getting to the Lanes Flat site.
  • Approximately 15 heavy vehicle movements in total will go through the Village between December 2015 and December 2016 which will be co-ordinated with traffic management and residents.
  • Lanes Flat plans should not impact traffic safety in the Village as education will be provided to users of the site. Including not using engine brakes. A survey will be undertaken to ensure contractors are complying with this training.
  • Contractors do not have the mandate to put up no engine brake signs. They can however encourage PCC/NZTA to do so if required.
  • Contractors cannot say there will be no environmental impact in building a 28km motorway. They will minimise that impact to ensure there is no net loss to the environment. The consent conditions require them to leave the environment in a better state than it is currently.
  • On a project this size they have large teams to manage safety, environment, quality, traffic safety.
  • Benefits which can be expected from the motorway include:
  • Sustained reduction in traffic on Grays Road and Paekakariki Hill Road.
  • Easy access between the North and South.
  • Better and safer walking and cycling connections for SH58
  • Negatives which may include:
  • Visual impact of motorway for some residents.
  • Noise impact for some residents
  • Noise and visual impacts will be masked as much as possible with timber noise walls and plantings.
  • Lanes Flat staff will have access to bathrooms etc onsite – hooked into Whitby Sewerage system. There is no accommodation on site.
  • Catering and food requirements for Lanes Flat staff are currently being considered. They will seek to support local businesses and look at all options.
  • Pedestrian access from Lanes Flat to Village had not been considered. Chris indicated this was a good idea he will look into.
  • Having 85 Auckland designers was a practical need as not all of these skills were available in the local Region. Chris indicated he would have preferred the majority of designers to be from the region if this had been possible.
  • Concrete batching plant at Lanes Flat is no longer happening. Concrete batching contracts are currently being priced. There could potentially be different providers at different ends of the Motorway. Chris could not estimate the impact on local road use for such transportation at this stage. Chris indicated they would address this is in one of the newsletters once the provider(s) were known.
  • Access to the Gully from Battle Hill area will be required to move in the Excavators and heavy equipment. They will come in through Paekakariki Hill Road. Once the equipment is in there it be working north and south along the gully route until it reaches SH58 in the south and SH1 in the north. So there will be no prolonged entry and exit of such vehicles.
  • There will be no continual movements of truck & trailers as the transportation of dirt will on average be only 900 metres. As one hill is cut, the next gully is filled. No fill material is planned to be moved across SH58.
  • SH58 will go underneath Transmission Gully, as will all local roads.
  • Lauren McKenzie indicated they welcome the opportunity to come back to the next PRA AGM to provide a progress update.
  • Please contact Lauren McKenzie ( or phone 0800 84 4636) if you have other questions
+ Text Size -

Skip to TOP

Do NOT follow this link or you will be banned from the server!