Evaluation of the Economic Impact of Proposed Non-Indigenous Species Control Measures for the St Lawrence Seaway Using Multi-Attribute Decision Theory

Mandatory ballast water management, resulting in an increase of required freight rates (RFR) on the St Lawrence Seaway, may cause modal shifts from the marine transportation mode to other modes. However, the modal shifts could well produce several undesirable side effects, such as worse air pollution, lower transportation safety, etc. To evaluate the trade-off between these and the positive ballast water management effects, a multi-attribute decision problem is formulated and solved, using the Analytic Hierarchy Process method, fuzzy set theory, and utility theory. A numerical example is presented. The results indicate that such modal shifts should be avoided, since the more the cargo is shifted from the marine mode to other modes, the more unfavourable the consequences are for the system.