Tuesday, February 14, 2006

Transmission Gully still not worth it

yes Transit still wants to build the coastal expressway instead of Transmission Gully. (the image is the profile of Transmission Gully compared to the existing route)
There isn’t the money for Transmission Gully – it is an uneconomic project and the media have been hoodwinked by Porirua City and the shockingly poor policy advice that sits within it. Porirua City Council does not know better than Transit, Greater Wellington Regional Council and peer reviewed consultants about roading costs – it just has a blinkered agenda. It wont raise rates to pay for Transmission Gully, even though its citizens would be some of the major beneficiaries. Porirua doesn't have the money - all the road user taxes from Wellington are committed for the next ten years (including the money that goes into the Crown account) - so it would have to be money taken from other government spending/tax cuts/borrowing to build a project with an economic return of 50c for every dollar spent on it. Wellington City Council has been trying to point much of this out - and it has a more credible policy department than any other Wellington territorial authority.
The coastal expressway does not need building now – the median barrier along the coast does, and that has funding from Land Transport NZ (see your petrol tax sometimes is spent well). The barrier costs around $16 million, 4-laning costs around 30 times that, Transmission Gully costs around 70 times that.
The focus for the corridor between Mackays Crossing and Paremata should be on a bypass for Pukerua Bay and a flyover at Paekakariki, which will make access in both communities safer and quicker. Congestion at Paremata has been ameliorated by the recently opened upgrade. Transit can pursue options for four-laning along the coast after that, and when congestion gets bad enough. Notice the road hasn’t been closed for a while – because it mainly gets closed due to accidents. When the barrier is up, there will be even fewer accidents and it will rarely be closed. With four lanes it is extremely unlikely all lanes will be closed at once – hardly worth an extra $500 million at that point, when you can use that money for something else – like remaining in your pocket!
The argument that Transit promised Transmission Gully and residents planned on that basis has some validity – but by no means was funding ever promised – the study that preceded the current round of consultation demonstrated that Transmission Gully was over three times what previous estimates had been.
Besides that the other components of the Western Corridor plan are difficult to argue against, the Kapiti Western Link Road (as a 70km/h arterial please!), extension of the rail service and higher frequency services, the Petone-Grenada link road and some other improvements are all worth proceeding with.
The next step is to see what the conclusion of the hearings panel are, and then the final recommended corridor plan adopted by the GW regional council and Transit. By the way, a good question and answer summary is on the GW website here and the whole proposed Western Corridor plan on a pdf document here.


Anonymous said...


I'd be interested to know why you have such an interest in Transmission Gully? (adise from living in the region?) Having a background in civil eng. myself, its fascinating as it is unaffordable and unworkable.
I too believe that the coastal road is the only choice and that anyone who sees TG as a savioural highway has a hidden agenda that is without logical economic grounding.

I would hate to imagine how much it is forecast to cost with inflation (at the rate its going) by the time they get started (lets hope not). Predictions of over the Big B(illion) shouldn't be too far off, especially if, while constructing it, they come across some geological minefield (which is more than likely - look at what they found for the piles at Lindale!)

I've read your past posts on it avidly and await more in the future.


Libertyscott said...

Seamonkey, I have been very close to this issue professionally for the past four or so years, so I have read reports and it has never stacked up. Before then I knew people who were fervent advocates and it is often advocated by those who reject the Green perspective as if building new roads is always good. I was a Wellingtonian as well, so had a personal interest in it as I used the corridor (rail and road) from time to time.

cheers, glad you appreciate my posts