So the proposed City Rail Link has been unveiled and Auckland Transport's plan is that it runs through Britomart, under Albert, Vincent and Pitt streets, then beneath Karangahape Rd and the Central Motorway Junction to Symonds St before rising to join the western line near Eden Terrace.
There'll be three city stations - at Aotea Centre, Karangahape Rd and Newton - and an interchange next to New North Rd. The link is made up of two 3.5km twin tunnels up to 45 metres below the city, which is good news as far as protecting any heritage buildings on top (if that is a concern to anyone these days).
It's estimated to cost $2.4b, along with the buy-up of $231 million worth of property (at today's prices) along the way.
Problem is, that's the cheap option - the one that filled the brief to be "the least-cost, engineering solution". The sensible option - one that would take it to the growing Wynyard Quarter, as well as up the hill past the hospital and on to 40,000 potential commuters at Auckland University and 18,000 more at AUT - seems too expensive.
According to Stephen Selwood, CE at the NZ Council for Infrastructure Development (NZCID), an extended route taking in Wynyard and the universities would add 1km and around $500m to the price tag.
I'd rarely suggest council spend more, but it doesn't seem a lot in the grand scheme of things to capture such a customer base. Mr Selwood says that $500m is based on the NZCID's estimate that tunnelling costs around $200m-$300m per kilometre, plus a couple of extra stations.
"If you don't serve those areas with rail then you must add the costs of buses or light rail," he points out. "What's needed is a 'whole of life, whole of city' analysis".
AT's plan has delivered what was required - the cheapest, shortest route. The Government has not yet committed a cent and, aside from not being flush with cash, may well be waiting for the City Centre Future Access Study due back from Auckland Council next month.
That study looks at all transport options - bus, rail, light rail and ferry. In the meantime it seems, Auckland Transport is putting it out there for discussion.
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