Metlink said there will be significant delays for commuters travelling out of Wellington Station.
Metlink spokeswoman Emily Liddell said they had a power outage earlier this morning just outside Wellington Station.
She said the situation had "changed a lot" since then but they have currently had to suspend all trains across the whole network.
Metlink said an "obstruction on the overhead" has caused damage to multiple trains and all trains that had been through the damaged section of lines would need to be taken out of service.
They would need to be inspected to prevent further damage to unaffected trains or overhead power lines.
It said they had sourced limited train replacement buses and regular buses are accepting rail tickets.
Commuter Julia Osborne was travelling into town from the Hutt Valley when the trains were stopped.
"We were stuck for about half an hour just out of Wellington Station whilst we waited for a platform to become available," she said.
"It wasn't too bad although I did miss a morning meeting because of it - but I would rather be stuck on the train than in the cold at the station."
Another woman said she caught the train from Wallaceville at 7:42.
"The train made it as far as Ngauranga when we were told everything seemed fine," she said.
"The poor ticket lady was then informed there were big delays."
There was about a 40 minute delay for the train to dock.
Shae Keenan was on the Porirua express train as it was stuck on the tracks for half an hour.
Meanwhile another woman waited for a train in Porirua for nearly an hour before one finally arrived.
But by the time the train reached Kenepuru they were told the trains were being suspended again and they would have to take replacement buses.
The buses were "already packed to the brim", however.
She ended up catching a $30 Uber, missed two hours of work, had to cancel a meeting, and spent her morning waiting in the "freezing cold".
Greater Wellington regional councillor Daran Ponter said it was "disappointing" all the trains were suspended today, especially given Wellington had experienced another system failure not long ago.
"We've just all been getting fed up with it."