With tree branches rupturing a diesel fuel tank and air lines of the northbound XPT last night, local firefighters say the incident could've ended up a lot worse for the 21 passengers and staff on-board.

A storm created havoc north of Grafton on Tuesday night, and the XPT passenger train hit trees that had fallen across the track.

>>> ORIGINAL STORY: XPT damaged as storm hits over Clarence Valley

Grafton Fire and Rescue 306 station captain Garry Reardon said two tankers, including Hazmat, as well as Trenayr Rural Fire Service attended the scene at Warragai Creek.

"The road to the train was about 1km off the Summerland Way, and it wasn't a bad surface, but the locomotive was another 800m further up the track, which meant we had to walk the full length to get to it," he said.

"They hit the tree at about 6.20pm, and we got called around 7.20pm."

When they arrived at the locomotive, they arrived to the driver and staff assessing the situation, with the trees wedged under the tree, and flying up as they went under the carriages.

"The trees had ripped the air lines, which had locked the brakes which he was trying to get off," Mr Reardon said.

"And they had also ripped away at the side glass of the fuel tank, with the diesel spilling up out of the bottom.

"We didn't have the containment equipment when we first went up, instead we had wooden wedges that have different sizes.

"We put Denso putty on the tanks, and then wedged on of the wooden wedges which stopped the leak."

Mr Reardon estimated around 600L of diesel had spilt out, which was contained by the hazmat crew, with more fuel left in the tank.

In near darkness, the firefighters and other emergency services set up lights along the long track to help evacuate passengers down to a staging area.

"We set up a covered area, and we had lighting so people could see off the track," he said. "It wasn't too bad, but it was a bit precarious.

"Eighteen of the 21 passengers were able to walk the 800m down the track, while ARTC had a car which the wheels locked onto the track and they ferried three elderly ladies one at a time that were unable to walk the distance.

Mr Reardon said the passengers were taken away by a bus, which had to reverse the 1km off the Summerland Way as there was no room to reverse where the train was.

None of the passengers were injured, and according to Transport for NSW, coaches replaced the train service for the remainder of the trip.

"It could've been a really nasty incident, but it worked out really well," Mr Reardon said.

"It was a really good outcome, but a very late night."