The drive through one section of Northland is notable for the kilometres of concrete sleepers stacked up by the rail lines, but no work is going on and there are no trains

Northland rail has been struck by New Zealand's 'do nothing' approach to infrastructure.

A plan to rebuild a railway line north of Whangārei has been put on hold again - years after it was deemed uneconomical in the first place.

The on-again, off-again plans have raised questions over whether the government's regional investment cash is going to the right projects.

Today's episode of The Detail looks at the convoluted and complicated history of the railway line rebuild.

RNZ's Northland reporter Peter de Graaf says the section from Kauri, on the northern outskirts of Whangārei, to the Ōtiria railyard, near Moerewa, was mothballed in 2016 for commercial reasons. The line from Swanson in west Auckland to Whangārei remained but was in need of serious work.

"In 2020, the Labour-NZ First government came along and dedicated a big chunk of money to upgrade the whole line and that included re-opening that last section from Kauri, all the way up through Ōtiria," de Graaf says.

"That was a government that was very keen on rail... part of the drive there is to take vehicles - trucks in particular - off the roads. Everyone knows the struggle that Northland has with its state highways."

Then work began - but not for long.

"KiwiRail ordered a huge amount of rail and sleepers.... they got tens of thousands, maybe more ... they were all taken and delivered to the railway line and stacked up neatly there along the line for 100-odd kilometres... and that's when the work seemed to stop."

After he "couldn't stand the mystery anymore", de Graaf asked KiwiRail what was going on.

He found that while $33 million had been spent, the work was now on hold.

De Graaf explains there were a few reasons for this - a local hapū was opposed to the line being reinstated and resources were diverted to fix up the line from Auckland to Whangārei after the storms of early 2023.

There are also plans to build a rail line out to Northport and KiwiRail says it doesn't make sense to re-open the most northern part until the port line's done.

De Graaf says part of the funding came from the Provincial Growth Fund and New Zealand Upgrade Programme, both initiatives of the Labour-NZ First 2017-2020 government.

He calls the funding a "mixed bag".

"I suppose the ones that get attention are the ones that do fall over - this is a classic example - there are many however that we up here in Northland have benefited from."…

Go to this episode on rnz.co.nz for more details