Spatial models representing the international grain economy are developed to estimate the annual contribution of the upper Mississippi and Illinois rivers to Midwest grain producer revenues and to evaluate alternate grain routing necessitated by a catastrophic event at Lock and Dam 27 near St. Louis. Several scenarios are constructed to consider grain load capacity constraints in combination with alternative rail rate increases. The analysis suggests the annual value of the upper Mississippi and Illinois Rivers for grain transport ranges from $229 million to $806 million.
