[Ted Davisson]

Greetings From New Orleans ,
Just one other aspect of High River navigation that has not yet been discussed or mentioned is simply getting under the six major bridges that exist between New Orleans and Baton Rouge . Even in low water the bridges are a major concern and especially now when we have anywhere from ten to fourteen more feet of river and the same amount of less bridge clearences . On ships we refer to the overall height of a ship as it's Air Draft and to get the overall height of any given bridge , we subtract the local river stage from the height of the bridge . For example , the Huey P. Long use to have a vertical clearence of 153 feet at zero river stage and now due to the ongoing widening of the bridge , the bridge has actually sank one to two feet . Now , with a river stage of 16.5 feet , we only have 136.5 of vertical clearence or less . Most standard Panamax class ships have an Air Draft of 130 feet when in ballast so that would only leave approximately 6.5 feet of clearence for the ship to safely pass under the bridge . Also , as I recall the Str. Mississippi Queen had some " issues " with some abandoned high line towers on the Upper Mississippi River some years back , so even the vessels with much less Air Draft must be aware of both river stages and bridge and high line tower crossing heights .
Smoothe Sailing !
Ted Davisson