Northland is to get the first new rail line to be built in New Zealand in over 50 years - to Marsden Point. It comes 15 years after Port Whangārei moved there, and almost 20 years after Northland Regional Council moved to designate the route and commence land purchases.
Politically, we have had a disappointingly muted response to the announcement that the Oakleigh to Marsden Point spur would finally be built, fully funded, under the NZ Upgrade Programme.
Perhaps that is because the much-vaunted, four-lane highway has been canned in the process, but what a great strategic opportunity this creates.
It is sad the highway project is off the 10-year plan for now, and that the entrance to Whangārei city remains a scruffy, unsafe, dog's breakfast. It is also enigmatic that the road between two well-upgraded intersections at Portland and Loop Rd will be forlornly incomplete for a while yet.
Perhaps we could consider that, in terms of road quality, four-laning all the way to Marsden Point was a step too far and much more than the existing road needs.
Perhaps some scaled-down safety improvements over a shorter distance might fit the bill meantime. While they look terrible, those yellow sticks are actually doing their job.
When Port Whangārei moved out to Marsden Point about 15 years ago, the Northland rail tonnage dropped from a million tonnes a year to about 300,000 tonnes. Back then, Tranz Rail was a private company and the consenting commissioners could not fetter an extended rail link to the port relocation.
Rail then had a downward spiral of lack of commercial performance and under-investment such that it almost closed down. Back in 2010, the elected government owned KiwiRail, and said the Marsden Point spur was essential to the future viability of the Northland line. It wasn't until five years ago that Northland rail found an influential political champion in NZ First.
Rail has been the orphan of our transport network for too long. It is great to see the Northland line having an around $100 million upgrade and the Marsden Point line becoming a reality, potentially opening the Auckland freight market to Northport.
This could help create a much-needed rationalisation of the Upper North Island port scene. Once the spur is built, it is up to private enterprise to realise the commercial opportunities.
But strategic common sense is one thing, getting a business case across the line is another. You can only measure what you know about and business viability is identified as the benefit-cost ratio (BCR).
This endeavours to quantify current and future costs and benefits and discount them to a net present value. Costs are immediately in front of you and can be reasonably calculated. The Marsden Point line was costed at $80 million in 2010. These now appear to be about $300m.
Benefits occur after the job is complete in three to four years' time. We can immediately identify emission reductions, trucks off roads, reduced road maintenance, road safety benefits and improved transport fuel efficiency with perhaps a million tonnes of logs transferred.
Less quantifiable is what happens at the port and wider considerations of taking the pressure off Auckland ports, shipping company preferences and the related Auckland congestion issues.
The benefits may be decades down the track. The best-case scenario in the business case is a BCR of 1.19.This means that for every $1 spent, you get $1.19 back.
Often major infrastructure projects have quite different outcomes from those projected. Wellington's Transmission Gully, for instance, had a contracted cost of $850m and a reported BCR of 0.6. The new road will open later this year at a cost of currently $1.25 billion, a 50 per cent blowout, and who knows what the current BCR is.
These decisions are often made strategically with the BCR as one component of that. There's no doubt about the strategic potential of the Marsden Point spur and it's great for the future of Northland that it will finally be built.
• John Williamson is chairman of Roadsafe Northland and Northland Road Safety Trust, a former national councillor for NZ Automobile Association and former Whangārei District Council member.