The New Zealand Transport Agency might not be Option X's biggest fan, but it has conceded the controversial proposal could deliver the same benefits as a flyover.
The concession came from the agency's transportation expert Peter McCombs this morning during the Basin Reserve flyover's board of inquiry hearing.
A four-member board is considering the transport agency's application to build a two-lane highway flyover, 20 metres north of the historic cricket ground.
The two-month hearing is now in its second week.
Option X has been proposed by the Architecture Centre as an alternative option. It involves forcing all local traffic to the west of the Basin and separating it from highway traffic via smaller overbridges at the Sussex/Buckle St intersection.
The transport agency considered the proposal back in 2012 but opted to forge ahead with a flyover design.
Today, board member David McMahon asked Mr McCombs whether he thought Option X would achieve the same strategic benefits as a flyover, if it had been put before the board instead.
Those strategic benefits include separating state highway traffic from local traffic at the Basin, improving journey times for private vehicles and public transport, improving safety, and making the highway more resilient against breakdowns.
"Can I give it a tick against the strategic options? Yes. It amounts to grade separation ... it was worth exploring for that reason," Mr McCombs said.
"But it failed in its delivery. I mean, I can picture all sorts of grade-separated options ... fifty years ago they were talking about running Kent and Cambridge terraces under the Basin itself."
One of the main reasons why Option X was not pursued was because of cost, Mr McCombs said.
The transport agency said it could cost up to $255 million, compared to $90m for a flyover.
Mr McCombs also questioned whether Option X was too complex to be constructed.
- The Dominion Post
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