Trains are returning to the Northland railway line after it was closed for 20 months to rebuild from Cyclone Gabrielle and the Auckland Anniversary Floods.

KiwiRail chief asset development officer David Gordon said there were more than 200 damaged sites along the 180 kilometre railway.

"It's been a huge undertaking to rebuild the line. Working with our contractors, we have moved more than 110,000 tonnes of earth - the equivalent of 28 Olympic sized swimming pools, laid more than 25,000 tonnes of ballast and made repairs to 28 wooden bridges."

He said 500 metres of retaining structures were installed as part of a drive to improve the line's resilience, as well as strengthening slip-prone slops and improving drainage.

Photo: KiwiRail

Trains will begin running again to consolidate the repaired track before freight services resume.

"This is a major change for communities between Swanson and Kauri (north of Whangārei) after 20 months with few trains and rail vehicles travelling on the line," Gordon said.

Drivers and pedestrians had become complacent around level crossings, and with trains running again, they needed to be more cautious, he said.

"Trains cannot stop quickly, so to ensure safety we urge everyone to be extremely cautious every time they approach a level crossing.

"Always stop and look both ways for trains before crossing the tracks. Never cross if a train is approaching, as they are usually travelling faster than they appear, and always wait for the train to pass."

This story was originally published by RNZ