Waterview tunnel: When will it open?

The delayed opening of Auckland's $1.4 billion Waterview tunnel is costing motorists millions of dollars a month in lost time, says former transport director Gary Taylor.

Taylor is unimpressed with the New Zealand Transport Agency, saying motorists have put up with years of delays with the widening of the northwestern motorway as part of the tunnel project and deserve to know what is going on.

"Speaking as an Auckland commuter who goes to the airport regularly from the west, it (the tunnel) was promised to be opened early this year, it was delayed until April. We are now at the end of April," said Taylor, who chairs the Environmental Defence Society and is a former director of the Auckland Regional Transport Authority.

We are working towards opening the tunnel within the next two months

Brett Gliddon, NZTA Auckland highways manager

Taylor said nobody would argue safety should be compromised but the lack of an explanation made him suspicious.

"The delay is costing I would think millions in lost time in each month that goes by and Auckland commuters are bearing those costs unnecessarily," Taylor said.

NZTA Auckland highways manager Brett Gliddon said the problem causing delays was an intermittent fault in the software for the jet fan and water extraction pump system which are part of the deluge system.

"Changes are being made to the software to remedy this, and parts of some valves are being replaced."

Gliddon said NZTA denied suggestions that the ventilation system inside the tunnel is inadequate.

"The transport agency and Well-Connected Alliance is working to open the Waterview Tunnel as soon as possible and will not compromise on safety and reliability. We are working towards opening the tunnel within the next two months," Gliddon said.

He said any extra costs will be shared between NZTA and the other parties in the Well-Connected Alliance.

On February 28, NZTA told the Herald the "Waterview tunnel is on track to open in April 2017", saying there were a number of logistical and safety issues to be worked through.

On March 24, NZTA said the opening had been delayed up to three months due to continuing testing and commissioning of complex systems to ensure the safe operation of the tunnel.

Labour's Auckland Issues spokesman and Te Atatu MP, Phil Twyford, said he did not think Auckland would have a problem with tunnel delay costs if they were confident of the benefits that were promised.

"What smells fishy is the delay of the opening. When NZTA announced they were going to stick traffic lights on the motorway to ration the numbers of cars entering the tunnel people all around Auckland were rolling their eyes.

"I think NZTA don't know what is going to happen to traffic volumes at peak hours when they open those tunnels. There is a real risk we may see at peak times severe congestion, particularly on the northwestern motorway," Twyford said.

He said NZTA and the Government had not learned that if you just build more motorways without a rapid transit system, the motorways fill up with cars and cannot cope with peak-hour demand.

"That's why we have had this debate about the unbelievably stupid decision not to build a rapid transit busway on the SH16 when they did the widening," Twyford said.