A record grain harvest has clogged the railway system in western Canada, frustrating farmers and grain companies that want to move that grain to export.

Industry officials estimate this season's crop is at about 65 million tonnes, which is above the 10-year average of about 47 million tonnes.

With such a large crop, grain is piling up in elevators and farm yards, while farmers fear they're losing money because they can't get the grain to port on time.

The large crop has maxed out the capacity for railway companies like CN Rail and CP Rail to move it from elevators to ports such as the one in Vancouver.

CP officials told CBC News the company is moving more grain this season than it ever has in the past.

Limits on capacity

CN Rail spokesperson Jim Feeny said trains are moving the grain as fast as possible, but warned that adding more rail cars to the system would not make any difference and could actually make the problem worse.

"Think of a freeway at rush hour. If you throw too many cars onto the road, the road plugs and everything backs up and slows down," he said Wednesday.

"If you throw more rail cars into the system, you going to get exactly the same result."

Feeny said the rail company recently spent $100 million upgrading its western Canadian network, but there are always limits on capacity.

"A crop that takes a summer to grow, especially a big crop like this one, just cannot be moved in three months. It's physically impossible," he said.

But the Western Canadian Grain Elevator Association says CN and other railway companies need to do more to help farmers move their grain.

"The problem was have is that it comes nowhere near the demand that we're seeing right now, so we really need the railways to look for creative ways to try and get more real capacity," said Wade Sobkowich, the association's executive director.