Newfoundland and Labrador's minister of transportation says repairs to the collapsed ramp on the Trans Canada Highway near Pasadena may take months.

An off-ramp and a large section of the west-bound lane collapsed early on Tuesday due to rising water levels in Deer Lake.

Transportation Minister Paul Davis said his department has sent experts to find out where the problem started.

"We are conducting a full investigation into exactly what took place near Exit 12 on the Trans-Canada Highway," Davis said.

Davis added the road is about 20 years old, and the water levels reported in Deer Lake were the highest in more than 30 years.

"As a result of that, there was a movement of the road and a separation as we've seen — quite a significant moving in the road and separation," Davis said.

According to Davis, the level of work that needs to be done to ensure the road is made safe again will take time.

"This is going to be a significant piece of work to correct this area. This is work that's not going to be able to be done in days or weeks — it's a piece of work that's quite likely going to take several months to repair," he said.

Davis said until engineers complete their evaluations, he will not be able to provide a timeline. He added that conditions are being monitored 24 hours a day to ensure no sudden changes in safety to drivers.

One west-bound lane of the highway is still in use, and motorists are advised to use Exit 14 as an alternate route.