Waihenga Bridge at Featherston remains closed because of flooding.
Earlier, in South Wairarapa, emergency services were called to Wood St when a car became stuck in floodwaters and would not restart.
A police spokeswoman said no injuries were reported.
Flights in and out of Wellington have also been cancelled.
Wellington Airport's departures and arrivals board was showing five cancellations and 10 delays about 12.20pm.
Numerous train services were disrupted because of slips and fallen trees around Wellington and Kāpiti.
A tree fell on the train line near Pukerua Bay about 7am, meaning the trains between Paekākāriki and Waikanae had to be halted and replaced by limited buses.
Meanwhile, a slip on the train line between Wellington and Ngaio also caused cancellations, with buses replacing the service and passengers advised to seek alternative transport.
"The bad weather has caused multiple tree falls and slips across the New Zealand network," a KiwiRail spokesperson said.
"KiwiRail staff are working as quickly as possible to safely clear the obstructions."
