A bumper grain crop in the prairies is causing headaches for drivers in Thunder Bay.

The record harvest means more freight trains rumbling through the city, causing delays along the line that crosses several of the city's major traffic arteries.

Tim Heney

Thunder Bay Port Authority CEO Tim Heney said this year's grain harvest is the largest in Canadian history. (Nicole Ireland/CBC)

"It's the largest grain crop in Canadian history," said Thunder Bay Port Authority CEO Tim Heney.

About 1 million tonnes of grain came in by rail last month to the elevators on Thunder Bay's waterfront.

Heney said that although the shipping season ends soon, trains will keep rolling in.

"Once the season ends, they're going to probably keep bringing those cars 'til they fill the elevators back up," he said. 

Heney said the terminal's storage capacity is about 12,000 rail cars.

1,000 cars per week

A spokesperson for CN said the frequency of trains has definitely increased this year.

"What we're seeing is sometimes over 1,000 grain cars a week coming into Thunder Bay on CN alone," said Jim Feeny.

Feeny said each train can run as long as 170 cars, and the law sets no limit on how long a train can block a crossing — as long as it keeps moving.

In one situation at the Memorial Avenue crossing last week, drivers waited 15 minutes for a train that was moving through.