Their interim business case says the heavy rail option would cost between $2.6 billion-$3 billion, while for "similar transport benefits" the light rail trams - from the southern end of Dominion Rd, would cost $1.2 billion-$1.3 billion. The benefit-cost ratio of heavy rail was 0.37-0.64, compared to light rail's 1.11 to 1.72.
Travel time estimates were about the same, with heavy rail from Britomart to the airport at 39-42 minutes and light rail 42-44 minutes.
But AT continues to dither. It's now requested a comparative study with rapid bus including, presumably, the driverless option.
For road-obsessed NZTA, it's another victory. As with the Waitemata Harbour Crossing designation study, the road builder has forced heavy rail off the agenda for all time. Yet with rapid transit to the airport not on anyone's "to do" list for at least 10 years, the least we could have done was to leave open the train option for those facing the ultimate decision.
In 10 years time, with arterial roads like Dominion Rd grid-locked for hours on end, Dr Levy's successors might have been grateful for the protected heavy rail route alternative we bequeathed them.
Dr Levy's "stunned mullet" turn on TV3 on Monday night underlines the situation. Pointing out that with airport arrivals growing at more than one million a year, and with no plans for improved rapid transport into town for a least a decade, the reporter asked him: "How will the current system cope with [this] growth?"
There was a long silence from the AT chairman. Then a nervous, "I've wet my pants" sort of grimace as he stuttered, "Good question."
We shouldn't be closing off options when the only "solution" on the table is a pie in the sky light rail system, which looks great on paper, but which has two major question marks hanging over it. First, who is going to fund it? Second, how do you retrofit one of the city's busiest roads with two rail tracks, then run trains, ultimately, at five-minute intervals?
It's a problem Dr Levy and his board plan to shuffle on to their successors. In which case, AT and NZTA should do the right thing and leave all options open.