John Williamson: The long road to a new road

The Puhoi to Warkworth Road of National Significance is set to open within the next month. Photo / NZME

OPINION

In another life 40 years ago, I attended an all-day monthly meeting in Auckland. I would leave home at 6.45am, and after driving moderately through Albany and the North Shore residential area, over the harbour bridge and past the old railway station, I could confidently make my meeting in central Parnell by 9am. Sometimes, the biggest hassle was finding a park in the company carpark. How life has changed.

I attended a Northland Regional Transport Committee meeting in the early 2000s and heard the Auckland manager of Transit NZ talk about the next stage of Alpurt — the Albany to Puhoi Northern Gateway extension. His somewhat cynical comment was that “it will get drivers to the end of the queue quicker”— and so it has transpired. If you wanted to get to Parnell by 9am now, you would need to leave Whangarei about 5.20am and take your chances with the end of the queue.

The need to build new roads has been a controversial question for many years amongst the demands of population growth, land development, health, education, social and recreation services alongside economic development and climate change, all of which compete with for a share of the public purse.

The steady and significant population growth of Auckland, and the requirement for new infrastructure to keep up, will mean the further extension of Alpurt — the Puhoi to Warkworth Road of National Significance, set to open within the next month.

The original 2016 price of $710 million has ballooned to $880m with multiple factors being implicit in the increase. The blurb from Waka Kotahi attests that, “This new motorway will provide increased safety, more consistent travel times, create a more robust and reliable road between Auckland and Northland, and provide a more reliable freight connection between Northland and the upper North Island. This is expected to support the economic and population growth of the area, and reduce congestion at Warkworth.

“Time savings are expected to be greater for trucks due to reductions in grade and better road layout, which helps heavy vehicles maintain a higher average speed along the route. Usage is expected to climb from 20,000 vehicles per day to 31,000 vpd in 10 years time, and a separated highway with a central median barrier and improved road design will greatly improve road safety.”

The new road was, at one stage, being identified as a toll road but the weight of Northland public opinion eventually won out, and the new road will not be tolled. While the speed limit on this new road has not yet been decided, it has been built to a standard that would qualify for a 110km/h speed limit.

But what is the real value of about eight minutes’ travel time saved, against the $880 million cost and the opportunity cost of other services that could be provided with that money? There are plenty of people prepared to debate that, and the frustration for many researchers is, that the business case assumes ascribed benefits, which may or may not be achieved or measured, after the project is complete.

As a balance to this, the AA Research Foundation recently released a study entitled The Safety Benefits of New Roads. This research studied crash data surrounding eight new bypasses constructed in New Zealand between 2009 and 2016. The study considered crash data for 10 years before and 10 years after the new roads’ completion. The research extracted data for both the new and old roads, as well as the surrounding roading environment.

Of relevance to the Northland area is the Northern Gateway — the toll road between Orewa and Puhoi, completed in 2009. The study indicated the new and old roads had a 43.5 per cent reduction in deaths and serious injuries along with a 5.5 per cent reduction in the surrounding roading environment. This means the new road had a significantly positive safety benefit on the whole local roading network.

The study does not try to turn these road safety benefits into money, but the Northern Gateway outcome is reasonably consistent with the outcomes of all eight new roads taken together. The study gives a pretty significant endorsement to the value of new roads, based on road safety benefits alone.