Rise in Water Levels in Mississippi River

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MARCH 26, 2008

RISE IN WATER LEVELS IN THE MISSISSIPPI RIVER

Your Managers have been informed that the Mississippi River is presently at 12.3 feet at New Orleans Carrollton Gauge and rising.  It is projected that, on April 8, 2008, the river will crest at 16.5 feet.  This water level is the highest since the very active 2005 casualty year.

The river has higher than normal high stages about every three to four years due to El Niño and La Niña cycles.

If at any time the river is above 15 feet at New Orleans, the Mississippi River Crisis Action Plan goes into effect.  More importantly, any time the river is above 14 feet more collisions, groundings and breakaways typically begin to occur, especially with Panamax bulk carriers or oil tankers loaded to more than 40 foot draft.

Charterers and shippers often think that higher river levels mean they should load vessels deeper and maximize profits, when the reverse is true.  At high river, the current scours away and collapses the dredged navigation channel edges, and renders deeply laden vessels more difficult to manoeuvre.  Equally, when moored, deeply laden vessels need all their lines out and constant tug attendance to avoid breaking away.  Many upriver midstream facilities such as at Mile 170 - 177 AHP are especially dangerous and prone to deep draft vessels dragging anchor and breaking away. Likewise Mississippi river anchorages above AMA/St. Rose up to Baton Rouge are susceptible to vessels loaded to more than 40 foot draft dragging anchor as long as the river stage is above 14 feet.

It is highly likely that, even now, some vessel somewhere has just received revised voyage instructions from the charterer/cargo shipper directing the master to load to a draft of 45 feet or to 47 feet instead of the normal 42 feet for Mississippi River port discharge.  Instead, they should be reducing the draft to 40 feet.  Owners and charterers need to talk about this situation and who will bear the extra expenses of tugs and pilots and lightering and, in the event of a grounding, consequent refloating expenses.

Members are encouraged to refer to www.srh.noaa.gov/lmrfc/forecast/rva.shtml for the National Weather Service Lower Mississippi River Forecast Center.