Ask Phoebe: Under-harbour route to surface near Onewa Rd

Tunnel traffic will bypass the Harbour Bridge. Photo / Greg Bowker

Many months ago I wrote to ask where the road under the harbour would end up on the North Shore. My understanding was that it would emerge around Esmonde Rd. If this is the case, this is simply shifting a bottleneck from one side of the harbour to the other. Is this, in fact, where the tunnel will end up? Roger Hall, Takapuna.

I apologise for the delay in responding to your question, Mr Hall.

The NZ Transport Agency said the preferred option would be made up of underground motorway and rail tunnels, to complement the existing Harbour Bridge.

The twin motorway tunnels would have three northbound and three southbound lanes. From the Central Motorway Junction, the tunnels would go underground at Victoria Park, underneath the harbour and resurface just south of the Onewa Rd interchange.

There would be upgraded connections at Onewa Rd and Esmonde Rd. The local road network in the area would also be upgraded to remove potential bottlenecks.

The proposed rail tunnels (what a good idea) would have one northbound and one southbound track. There would be a new underground station in Gaunt St, between Daldy and Halsey Sts, and this would link with a future CBD loop tunnel.

On the North Shore, the tunnels would emerge just south of Onewa Rd and connect to a station at Akoranga.

It is anticipated that by 2041 the rail option could cater for up to 30 per cent of all passenger trips across the harbour.

All of this is outlined in the Waitemata Harbour Crossing study, which narrowed down a long list of 159 options to a shortlist of three in 2007. The current proposal is now the single preferred option.

I understood there were to be lane configuration changes at the Wellesley St motorway offramps, specifically to allow left turns from the right-hand lane as well as from the left-hand lane. At the moment there is serious traffic build-up in the left lane and little traffic in the right. And what happened to the proposed change at Princes St, to allow a right turn from Wellesley St? Carole Van Weede, Auckland.

There is a proposal to upgrade the Wellesley St/Grafton Rd route, as part of the Central Connector works on Symonds St. Or should I say, there was a proposal.

Auckland City Council says funding has not been secured for this and so it's on the back burner for the foreseeable future.

Without these changes, the council feels allowing left turns from the right-hand lane will introduce merging problems under the Symonds St underpass. So the road markings will not be changed.

Thus, the status quo remains.