Grain shippers and producers are raising concerns about a growing backlog of rail shipments that they say is leading to lost sales and unreliable exports.

The Ag Transport Coalition that represents several grain associations says that car order fulfilments from Canada's two major railways was 38 per cent during the week of Feb. 12.

The coalition says Canadian National Railway Co. delivered 17 per cent of the rail cars that grain shippers ordered, while Canadian Pacific Railway Ltd. delivered 66 per cent.

Wade Sobkowich, executive director of the Western Grain Elevator Association, says shippers are starting to pay penalties because delayed rail shipments mean they don't have the grains ready to load at ports.

Grain producers say passage of Bill C-49 would be an important step in solving the problem by creating penalties for delayed railway shipments.

CN and CP did not immediately respond to a request for comment.