The following notice received from Mississippi River Bar Pilots:

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We are experiencing a record high river during this time of year. Bar  pilot's are experiencing a lot of problem's on inbound transits with  draft's around 35 feet or more with Slush. Some ship's like the  container vessels are able to move thru the slush without a problem but the loaded bulk/tanker's are having the problem's. Therefore to  try to avoid a serious problem in SWP the pilots would like to bring  in the load's 35 feet or above during high tide or as close as possible to try to avoid the slush. We are working with the CORP on > this problem and we will also try to reduce any delays to any vessel waiting for high tide to transit. I will keep everyone up to date on the progress in SWP.

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Slush is basically all of the extra sediments that the Mississippi River deposits around SW Pass due to the higher river conditions. This is in the form of sand, mud, etc., and can sometimes get to a slight jellified state. For the most part it slows the larger deeper vessels down because it causes drag on them. Other problems that may result is engine overheating depending upon whether a vessel's intakes for engine cooling water is high or low along the hull in the vessel's design. This may be the reason for the recent closure of SW Pass this past weekend due to the overheating of a ship's engine causing her to block the pass for a number of hours.