The proposed 3.2km long twin bore tunnels for New Zealand’s Waterview Connection scheme could be dropped after higher estimated costs led the Government to call for alternatives to tunnelling to be investigated.
New cost estimates for the tunnel project show a 46% increase to NZ$2.77bn (US$1.47bn) from NZ$1.89bn (US$1bn). The estimate, from the Treasury and Ministry of Transport, includes debt servicing. It is being developed by Transit New Zealand.
Restrictions on serving increasing demand are a further complaint against the project, which is would have two traffic lanes in each tube between Mount Roskill and portals at Hendon Park and Waterview Park. Taking the project up to three lanes in each tube would increase the cost to more than NZ$3bn (US$1.6bn), said Transport Minister, Steven Joyce.
Last year, it was envisaged that the plan then under approval by the then Labour Government would see work commence in late 2009. The tunnels would be excavated by TBM at a depth of approximately 40m and be lined with concrete segments (T&TI, May 2008, p8).
Joyce said: ‘The last Government allowed expectations to be raised about a number of large transport projects, including Waterview, without actually allocating funding to them.’
He added: ‘The Government is committed to delivering a Waterview Connection but wants to ensure the project is advanced in a cost-effective and future-proofed way.’
The Waterview link would have a total length of 5km and was planned to be finished in 2015, and so complete Auckland’s 48km long Western ring route.
