Could the Mississippi be expanded to accommodate ocean going ships?

As in the title, if the US government had the money and the political will could it transform the Mississippi to accommodate ships of a drought (depth a ship needs) of at least 13m?
 

Driftless

Donor
To Minneapolis - no.

The river and its many tributaries carry an enormous silt and sand load. I live in Western Wisconsin, close to the Mississippi. Corps of Engineer dredges are a fairly common sight in that half of the year that barge navigation can occur. Those dredges move huge amounts of dredging spoil that has to go "somewhere". Usually that's within a few hundred meters of where it's picked up - with significant environmental impact in the process, both to the river itself and to the area where the spoil is dumped. That's just to achieve a temporary 9'/2.75m depth in the navigable channel - the course of which changes..... The cost to attempt such an operation would be astronomical and perpetual.

Could you do more on the lower stretches of the river? Maybe, but again the cost/benefit is debatable.
 
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As a native South Louisianan (so slightly biased on this question), I ask to what end? Given the extensive truck and (especially) rail network concentrated around the river, why would the Army Corps of Engineers spend the money to dredge the Mississippi to deep-draft standards up towards Memphis or St. Louis? Would it really be that more cost-efficient to load grain on a freighter in say, Vicksburg or Memphis rather than Baton Rouge or New Orleans? Most of that grain is either barged or run by train to the big elevators that line the river between New Orleans and Baton Rouge. The various ports in SE Louisiana have already lost most of the intermodal shipping to Houston due to the fact that New Orleans is nearly 100 miles upriver from the Gulf versus 30-40 miles for the main port facilities in the Houston area. I just don’t see the economic impetus for spending the money to allow big oceangoing frieghters to travel hundreds of miles up the river when you can upgrade the existing rail or highway infrastructure at a slew of Gulf Coast ports to ship an increased amount of goods from the Midwest to the same ships at a much lower cost.
 
add in flooding that can last for weeks or months at a time it probably wouldn't be worth it.
 

SsgtC

Banned
I've heard, don't know if it's true or not, that the Mississippi is one of the most treacherous rivers in the world to try and navigate due to a number of factors. Among those the massive silt content and realativly high speed of the current. Those two factors combined tend to constantly shift where the navigable channel is.

This part I do know for certain. There are a number of bridges that cross the Mississippi that are no where near high enough to allow ocean going ships to pass below them. Air draft is just as important to a ship as channel depth. Some of these bridges are so low that sailboats with 55' air draft cannot pass beneath them without unstepping their masts. That alone would kill the project.
 
The St Lawrence Seaway & Great Lakes underwent in the mid 20th Century a massive expansion of the ability to service blue water cargo ships. It appears traffic never reached the hoped for levels and some of the capability has athropied for lack of traffic.
 

trurle

Banned
As in the title, if the US government had the money and the political will could it transform the Mississippi to accommodate ships of a drought (depth a ship needs) of at least 13m?
The only practical solution on upper Missisipi would be to make a concrete-lined channel parallel to the river - to alleviate the silting problem. Very costly compared to railroad of the same capacity. Imagine all the locks, pumps and silt settling ponds..well..may work if you restrict draft to 8.5m. Low-end ocean-going vessels (i.e. Liberty ships) has draft of 8.5m, reducing cost by 57% compared to 13-meter compatible channel.
 
In the deep dark recesses of my mind, there is a recollection of the bridge building schemes of one Hughie Long ... keep any bridges across the Mississippi low enough to preclude anything but river boats and barge traffic from proceeding up river. His reasoning was by restricting ocean going vessels from proceeding further north, there would be more money to be made in commodity and freight handling in the great state of Louisiana ... out of which a reasonable stipend would, in all likelihood, find its way to Mr. Long.

While the physical engineering of changes to the river to allow the passage of ocean going ships further up the river would be daunting in their own right, they might well pale in comparison to having to deal with Mr. Long's political machine in its heyday.
 
I've heard, don't know if it's true or not, that the Mississippi is one of the most treacherous rivers in the world to try and navigate due to a number of factors. Among those the massive silt content and realativly high speed of the current. Those two factors combined tend to constantly shift where the navigable channel is.

This part I do know for certain. There are a number of bridges that cross the Mississippi that are no where near high enough to allow ocean going ships to pass below them. Air draft is just as important to a ship as channel depth. Some of these bridges are so low that sailboats with 55' air draft cannot pass beneath them without unstepping their masts. That alone would kill the project.
Presumably if they are willing to spend the money to basically create the longest, biggest canal in the world, they can afford an extra trillion or so to also completely redo the road network along the route and build sufficiently high bridges.
 

trurle

Banned
Presumably if they are willing to spend the money to basically create the longest, biggest canal in the world, they can afford an extra trillion or so to also completely redo the road network along the route and build sufficiently high bridges.
St. Louis - Minneapolis channel is roughly 1000km. Cost is 5.5 times of Panama channel for 13m draft, and 2.4 times of Panama Canal for 8.5m draft.
 
In the deep dark recesses of my mind, there is a recollection of the bridge building schemes of one Hughie Long ... keep any bridges across the Mississippi low enough to preclude anything but river boats and barge traffic from proceeding up river. ...

Long was running with a idea around for sometime among New Orleans businessmen. The US and Confederate Navies had operated blue water warships on the Mississippi & in the pre bridge era blue water steam powered cargo ships had occasionally navigated up river. The engineering problems and cost were less well understood in the 1920s & after the construction of the Barrage that allowed consistent deep draft navigation to New Orleans it seemed reasonable the cargo ships might travel further.
 

Driftless

Donor
St. Louis - Minneapolis channel is roughly 1000km. Cost is 5.5 times of Panama channel for 13m draft, and 2.4 times of Panama Canal for 8.5m draft.

There are also 26 full service locks & dams between Minneapolis and Alton, Illinois(just north of St Louis). I believe the standard lock size is 110'/33m wide by 600'/180m long(depth is not listed in the CoE documents - variable, based on seasonal water levels?). Each one is a significant concrete and steel structure, usually with a several hundred meter wide earthen dam component as well.

Here's a representative example of the dredging sequence for the pool of Lock and Dam #8 Genoa, WI from 2017. That's just to manintain a 9'/3m navigable barge channel. It's a huge and perpetual expense to keep the bed clear. Where the dredging spoil gets dumped is usually a local political "hot potato" for both environmental and economic reasons.
 
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