Plans for Reducing Shoaling, Southwest Pass, Mississippi River. Hydraulic Model Investigation.

Abstract : Southwest Pass, one of the three major outlets of the Mississippi River, is the principal navigation channel between the Gulf of Mexico and New Orleans, La. At the time of the model study reported herein, it was being maintained to provide a navigation channel 35 ft deep by 800 ft wide from Head of Passes to the ends of the jetties (21.2 miles below Head of Passes) from whence a bar channel 35 ft deep by 600 ft wide extended into the Gulf. Maintenance of the channels is a continuing and expensive problem due to extensive shoaling, primarily near the ends of the jetties and to some extent throughout the entire length of the Pass. Most of the shoaling in the jetty channel occurs during time of high freshwater discharge. The model study was conducted to determine the effectiveness of proposed plans (jetty extensions and channel realignments and contractions) for the elimination or reduction of maintenance dredging in the jetty and bar channels, and effects of deepening the channels to 40 ft. (Author)