Tunnels 'add billions' to South Island line
The government has for the first time estimated the cost to put the entire South Island line underground as opposed to using a viaduct design. Briefing lawmakers yesterday, transport chief Eva Cheng said tunnels would add billions of dollars to the project. The government had not yet done a detailed cost comparison, however. 'But given the complexity of tunnels, we can say the difference would amount to several billion dollars,' she said.