http://www.reuters.com/article/2012/08/02/us-usa-drought-barges-idUSBRE8711KC20120802
I have often wondered how efficiently railroads in the Midwest are able to take up the slack when there are problems with barge traffic on the Mississippi. Does the CN, for instance, do any planning when it comes to car supply to move grain by rail when the river closes? I know that in past years car supply has been issue, and railroads were not able to take full advantage of the situation.