Assessment of Sedimentation Affecting Riverine Ports in Louisiana

Both the Port of Lake Providence and the Port of Madison Parish have suffered in recent years from record highs and lows of the Mississippi River. These events caused unique conditions to occur at both ports including excessive sedimentation at the navigation channel entry from the Mississippi River. This report was prepared in response to SR105, which directed the Louisiana Department of Transportation and Development (DOTD) to prepare a report on potential measures to address the sedimentation at two northeast Louisiana ports, as named previously. Sedimentation and other morphological processes degrade channel depth, which requires investment in either structural controls or periodic maintenance dredging to maintain required depth. Given these ports’ primary commodities are related to agri-business, which remains a highly competitive environment, lack of sufficient access to these ports can negatively impact their economies for both import and export commodities. The research team investigated available literature on sedimentation at harbor channels and previous studies conducted by the U.S. Army Corps of Engineers (USACOE) for both ports; they also conducted on-site investigations as well as key-person interviews. After this comprehensive process, researchers recommended the following: (1) perform a Least Cost Market Analysis to determine maximum market share potential at each port facility; (2) perform detailed morphological studies of the evolution of persistent shoals at each port facility; (3) evaluate alternative configurations of river training structures; (4) evaluate the construction of a weir near the Mississippi River in the existing chute that bisects Stack Island abutting Hagaman Chute; (5) further investigate the chute and bypass channel into the Mississippi River; (6) develop a dredge operations model for each port facility to determine optimum dredge operations required to maintain uninterrupted port access; and (7) review alternative procurement approaches of maintenance dredging contracts.