Transmission Gully: A motorway more than a century in the making

Thursday, 17 March 2022

A drone flythrough of Transmission Gully on October 1 shows the final stages of construction.

Are we there yet?

It's a common question from irritated passengers on a long car ride, and the Transmission Gully journey has spanned more than 100 years.

Delays, cost blowouts, and construction issues have dominated headlines about $1.25 billion project for decades.

In the 19 years since The Dominion Post was created, the phrase “Transmission Gully” has appeared in more than 1900 articles, columns and letters.

* Transmission Gully: Who is CPB, the Australian company behind the ongoing delays?

Transmission Gully from the air, taken by Leo Cooney, on January 18, 2022.

* Transmission Gully: Major repairs underway after surfacing issues

* Transmission Gully: Expert told Waka Kotahi road was safe to open in December

* Transmission Gully: Unfinished billion-dollar highway's bumpy road

However, the destination is finally in sight with confirmation the $1.25 billion motorway will open within the two weeks.

So, how did we get here?

Transmission Gully, past to present

1919: The Evening Post reports on a proposal by Otaki MP William Field for an inland motorway from Paekākāriki to Paremata – the earliest known record of a proposal roughly resembling today’s version of the road.

Official sod turning ceremony for project, in 2014 just north of Paekākāriki.

1924: A 110,000 volt transmission line is laid between Wellington and Mangahao Power Station in Shannon, giving the gully its name.

1995: The Wellington Automobile Association suggests Transmission Gully should be built as a toll road. Transit New Zealand estimates construction costs at $160 million.

1999: In an updated estimate, Transit New Zealand puts construction costs at $245m.

2009: Transport Minister Stephen Joyce announces Transmission Gully as part of the roads of national significance strategy.

Waka Kotahi NZ Land Transport Agency announced a change of State Highway numbers on the opening of Transmission Gully.

2012: Transport Minister Gerry Brownlee tells NZTA to consider a public-private partnership. This was largely due to the Christchurch earthquake, which put funding pressure on the Government’s balance sheet. By now, the cost estimate was $850m.

July 2014: NZTA signs a PPP contract with Wellington Gateway Partnership (WGP) to design, construct, finance, and then operate and maintain the new motorway for 25 years. WGP hired a series of contractors to complete each part of the project. CPB HEB is hired as the road builder.

September 2014: Prime Minister John Key, Brownlee and Wellington Regional Council chair Fran Wilde take part in a soil turning ceremony at the northern end of the motorway.

Copy photo of the front page of The Evening Post of August 21, 2000, featuring the poll results during the newspaper’s Why Are We Waiting campaign.

October 2015: Works begin on-site with a massive earthmoving operation, which will eventually dig up enough dirt to fill the Sky Stadium 2.7 times.

November 2016: The Kaikōura earthquake hits, followed by a season of torrential rain. CPB HEB warns the opening date of April 2020 could be pushed as late as August 2020. It’s the first official sign of trouble.

June 2019: Waka Kotahi agrees to a one-month extension due to delays from the earthquake, moving opening day from April 2020 to May 2020.

September 2019: The opening date is pushed back again, from May 2020 to November 2020. NZTA admits there have been more issues than it previously let on – storms had caused slips on some cut slopes and damaged a stream diversion project. In some areas the damage was so severe they needed to redesign the slopes entirely.

Feb 2020: Costs officially blow out to more than $1b after Waka Kotahi agrees to pay another $191m to Wellington Gateway Partnership due to the delays. A press release quietly abandons the November 2020 date, instead noting the builder is “working very hard to complete the motorway by Christmas”.

March 2020: New Zealand enters a level 4 lockdown. All construction on the road stops.

April 29, 2020: Work is able to restart, albeit without 80 staff, who are stuck overseas. The lockdown costs valuable time during peak paving season.

August 2020: After months of negotiations, Waka Kotahi agrees to pay WGP an extra $208 million. It brings the total cost to $1.25b – $400m more than originally agreed. The opening date is moved to September 27, 2021. As part of the deal, builder CPB HEB will face a penalty of $7.5m and $250,000 per day it opens late.

November 2020: Media are invited on a drive-through of the road. All major bridges are completed, but much of the road is still an unsurfaced, bumpy ride. Sergio Mejia, chief executive of Wellington Gateway Partnership, says the only thing that could delay the project again would be an earthquake or an unprecedented flood. What he didn't see coming, however, was another Level 4 lockdown.

July 2021: Paving is reported as 94 per cent complete. Waka Kotahi puts out a cryptic press release reminding WGP of the consequences if the road doesn’t open on time – but there is no official word that the opening day is at risk.

August 14, 2021: Greater Wellington Regional Council chairperson Daran Ponter warns that dozens of outstanding resource consents could put opening day at risk.

August 18, 2021: New Zealand enters a Covid-19 level 4 lockdown. Workers are given essential permits to access Transmission Gully for security, safety and environmental protection.

September 18, 2021: Waka Kotahi confirms Transmission Gully will not open by its September 27 deadline. No new opening date has been announced.

December 2021: Waka Kotahi's hopes to have the road ready and open for the Christmas holidays are dashed when the agency concedes builders have dozens of incomplete consents. It says the road will not open in 2021. No new opening date is issued, but Waka Kotahi says it will “likely” issue a statement in mid-February.

February 9, 2022: Large sections of the motorway’s surface are torn up and relaid after problems are found. Sources close to the project say issues with the chip seal and milling had resulted in water coming up through the pavement, causing surface flooding.

March 1, 2022: Road builders CPB Contractors issue a second letter to Waka Kotahi stating the road was ready to open. This followed an initial letter leaked to media earlier in the year saying the same thing.

March 17, 2022: Waka Kotahi issues a formal directive to its contractor to open the motorway by the end of March.