This project describes a methodology for assessing relative risk along a transportation corridor utilizing waterborne transportation on the busiest port area in the world, the lower Mississippi River (from the mouth of Southwest Pass up through Baton Rouge, Louisiana). The paper calculates a relative risk scale, using data obtained from maritime experts, previous research, and existing databases. The research aggregates the vessel traffic data and geographic risk location data to produce relative risk scores for each mile along the River from the mouth of Southwest Pass to the termination of shipping at the U.S. 190 bridge across the River at Baton Rouge. This is done in a very simple and practical way for this initial model: (1) each vessel traveling the Mississippi is classified according to its risk potential for those miles that it passes in route to where it docks, and (2) points along the river are assigned a relative risk score based upon risk variables identified by expérts identified through a standard sampling procedure. The relative risk scores for river miles are combinations of these two factors.