Extreme water flows on the Mississippi River

Our lawyers in New Orleans warns about the extreme high river and strong currents presently being experienced on the Mississippi River. According to the forecast the situation will last for the entire month of March and well into April.

According to the forecast, this year the river will be above 15 feet from 25 February 2019 until the middle of April 2019 – for more than one month – and will crest at 17 feet between 18 March and 24 March 2019. This is unusual and deserves our members’ special attention.

The high flows can result in the following:

– Groundings
– Anchor loss
– Windlass breakdown
– Delays (port call)

The National Weather Service for the Lower Mississippi River »

Information on the Mississippi flows from from Mike Butterworth, Phelps Dunbar LLP, New Orleans

The snowmelt and the strong spring rainstorms of late February through early April swell the river every year until it measures about 15 feet on the Carrollton Gauge, producing a river current in the 4 -5 knot range.

Ground Tackle for a loaded Panamax bulk carrier is rated to 4 knots – more than adequate for most harbours and anchorages in the world, almost all the time. But not for the Mississippi River in the late winter and early spring. Once the Mississippi River rises above 12 feet on the Carrollton Gauge, producing a river current in the 3 – 4 knot range, usually in early February, we start to see more anchor loss and windlass breakdown problems.

At some berths near big bends in the river where the current runs above average, deep draft vessels start to need hold in tugs to keep them alongside the wharf when their draft is more than 40 feet – even if they have put out every mooring hawser aboard to every wharf bollard or anchor buoy they can reach.

Likewise we start to see more vessel groundings – even though it seems like there should be fewer groundings because the river is higher. Charterers always want to load vessels a few feet deeper than normal when the river stage increases, when they should be loading a few feet less.

This is because the stronger current gnaws away at the dredged channel banks in all the crossings and collapses them into the center; and also causes shoals at the “breaks” in the river near Ama at Mile 110 – 115 and at Cubit’s Gap near Mile 3 – 4 where there is a break in the gradient of the terrain and river bottom and the river flattens out and slows a bit, dropping a tremendous amount of sediment. Shoaling of more than three feet a day can happen at the breaks – shoaling faster than the dredges can keep up with – which causes the pilot recommended loading drafts to decrease.

As the river rises from “low” high river at 12 feet on the Carrollton Gauge to “strong” high river at 15 feet on the Carrollton Gauge, the number of incidents pick up. Vessel delays are more common because mid-stream facility mooring/unmooring is restricted to daylight only, and because the icy cold water from the snowmelt in Minnesota meets the warm humid air of the Louisiana spring causing thick fog. Mooring hawsers start to render, and then to part, resulting in extra line handler expenses to re-run lines after the supplemental hold in tug arrives on scene to push the vessel back alongside the wharf. Now there are two hold in tugs pushing alongside the ship, at about $25,000 per day each. When the river reaches 15 feet sometimes at some berths there are three hold in tugs required, and a 24/7 standby pilot at $12,500 per day.

Now the charter party disputes start, with charter brokers who fix ships for the Mississippi River 365/24/7 acting as if they had never heard about Mississippi River high river conditions and the extra expenses required for safety. The vessel owners want the charterers to pay for the extra tug, pilot and line handler expenses, but the charterers claim the vessel masters are just being over – cautious. The local agents, usually hired by one of the charterers, always entice the vessel masters to come to upriver berths and mid-stream facilities – “the last ship made it, and no hold in tugs” – never mind the river has risen two feet in the meanwhile, and is forecast to keep rising.

When the river rises above 15 feet towards 17 feet on the Carrollton Gauge, is “extreme” high river. The river current now is in the 5 – 6 knot range, especially in the bends above New Orleans up to Baton Rouge. This does not happen every year, and even when it does, it usually only lasts a few days.

At “extreme” high river, many anchorages above New Orleans and the Ama “break’’ at Mile 110 can no longer accept fully loaded 47 foot draft bulk carriers – they simply drag right out of the anchorages – especially during a frontal passage or during strong thunderstorms with 40 mph wind. Usually at this point the USCG Captain of the Port and the pilots require “one way traffic, daylight only” which leads to further delays. A Mississippi River port call which normally would take three or four days and no tugs or pilots when moored/anchored, will now at strong to extreme high river take one or two weeks, or longer – and all the time with two or three assist tugs or hold in tugs – and often a standby pilot to control the vessel in case she breaks away. And all the time with the engine room fully manned and main engine running and ready for immediate maneuverer.

As for maneuvering vessels, between 12 feet and 15 feet down bound vessels with the current underfoot begin to experience difficulty maneuvering, especially when loaded above 45 feet. There is less and less margin for error. The pilots and bridge teams must hit the turns just right to make it round the bends. From 15 feet to 17 feet even the upbound vessels have trouble maneuvering, especially upbound loaded vessels who misjudge the point, and the current hits the bow broadside and tops the vessel around 180 degrees in her own length. And fully loaded down bound vessels are much more prone to swing wide around turns and come to grief against bridge piers, wharves, barge fleets, or stone revetted riverbank.

Needless to say, under these conditions any mechanical issues will result in an incident – there is no time to recover from a momentary main engine slowdown, or a ten second generator switchover black out.

Some owners are proud of their internal ISM/SMS audit program, and of their charterer vetting record, and are certain their vessel and crew are fit for the Mississippi River during high river – but there is no audit so merciless, no vetting so unforgiving, as that carried out by the Mississippi – “The Father of the Waters”. And even wharf owners and charterers must concede that during strong to extreme high river, there must be at least some additional tug and pilot expense, and some expected delays, for safety.

The Mississippi River usually does not rise above 17 feet Carrollton Gauge nowadays, since to protect the City of New Orleans levees the US Army Corps of Engineers closes the Bonnet Carre Anchorage and opens the adjacent spillway on the left descending “east” bank of the Mississippi River at Mile 127-129 to dump the top of the river into Lake Pontchartrain. But as local surveyors and lawyers will tell you, a 15 to 17 foot river is more than adequate to generate incidents. And this year’s river promises to be especially productive – unless all concerned take precautions and think ahead and work together mindful of the additional risk and expense so as to make their Mississippi River common adventure as safe as possible.

Member Alert is published by The Swedish Club as a service to members. While the information is believed correct, the Club cannot assume responsibility for completeness or accuracy.