In 1946 the Southern Authors Literary Guild chose "Speeding Floods to the Sea" as the most outstanding book of the fall. Pretty racy stuff. A book about cut offs - on the Mississippi River. The author W.E. Elam lived in Greenville which was known for its writers. He was not a writer though. He was an engineer. But not just any engineer. He was the Chief Engineer of the Mississippi Levee District and a respected authority on floods. Floods were a big deal in Mississippi then. They had a big effect on its farm-based economy. So Elam wrote the book about how to prevent or moderate them.
It's pretty simple: just speed the floods to the sea. The idea is to straighten and shorten the river by cut offs. The faded paper jacket on the book shows the river's meandering Greenville Bends. They looked like a winding country road with a super highway cut off going straight through. Cut offs shortened the river about 150 miles. They sped up its flow and cut a steeper slope and deeper bed in many places. So the river carried more water at lower levels (stages).
Cut offs were a controversial part of the Corps of Engineers' Mississippi Rivers and Tributaries Project authorized by congress after the great flood of 1927. The project was changed many times in response to shifting political alliances and pressures. The outcome was usually less flooding for somebody and more flooding for somebody else. Back in the day Mississippi's politicians held their own in flood trading. Mississippi didn't flood so much then. Now it floods a lot.
Half done. Elam's book documented that cut offs worked. But cut offs were just half the solution. The other half was to get the floods to the sea. The other half got lost in the political flood trading. So the floods now speed to Mississippi, not the sea. And the water stays in Mississippi's batture between the riverbank and the levees and hills for months now. Over 75,000 acres south of Natchez has been flooded since last December.
The missing rest of the story is the outlet to the sea. It was supposed to be a channel running south west across Louisiana between Natchez and Baton Rouge and discharging near Morgan City - roughly where the Morganza floodway is now. It would increase the river's discharge to take the increased flow from the cut offs. It didn't happen. So the faster greater flow now backs up in Mississippi.
Ground Hog Day. The Corps raised the levees to contain the increased flow that can't get out to the sea. It has built a bigger next flood disaster. The higher the levees, the higher the floods, and the greater the destruction when a levee breaks. We never learn. We seem caught in a Ground Hog Day time warp. The history of the river has been bigger and higher levees and bigger and more destructive floods.
When the levee broke at Mounds Landing north of Greenville in 1927, it flooded over a million acres 10 feet deep in a matter of days. Levees are higher now. Upriver development and runoff is greater now. The river is shorter and the flow is faster now. But it can't get out. Something's got to give. When one of the higher levees fails, there will be an even greater flood disaster.
Such a disaster could result from the recently completed $13 billion hurricane risk reduction project at New Orleans. This is supposed to protect against storm water surges from the sea. It includes stronger levees on the Mississippi as it meanders through New Orleans. It also includes capacity to pump more water from the city's low-lying areas into the river. The river is already maxed out and can't discharge floods coming downstream now.
Stepped over a snake twice. The city almost flooded in 2011 and 2016. Opening the Bonnet Carré spillway saved it. The hurricane risk reduction project may actually increase river flood risk. It constricts the river and increases its load. New Orleans could flood despite the $13 billion project if a hurricane hits when the river is high.
And the river is high a lot now. It stays high much of the year. Two one-hundred year floods in five years. The next flood comes before the last flood drains. Why? Because the only way more flow can get to the sea now (down the Atchafalaya via the Old River channel north of Baton Rouge) is limited by law. This 1964 law caps the flow down the Atchafalaya at a max of 30% of the main channel's flow. The Atchafalaya is the shortest and most direct route to the sea. It can handle more flow.
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A twofer. Increasing the flow year round (not just when floods threaten) would lower the water level in the main channel. This would reduce flood risk at New Orleans. This would also reduce batture and backwater flooding. Such flooding in Louisiana is not much of a problem because there's not much land in the batture from the Mississippi line to New Orleans. And the river there receives just 70% of the upstream flow. There are 550,000 acres of batture upriver in Mississippi, however, which get 100% of the flow. Its flooding is a big problem. It impairs property values, limits farming and timber and oil and gas operations, prevents hunting and other recreational activities, and reduces related business and tax revenues.
So Louisiana politicians don't care much about batture flooding on the Mississippi. They do care about flooding New Orleans though. Mississippi's politicians are learning about the problem and cost of Batture flooding and associated backwater flooding - which impacts another million acres. Sending more flow down the Atchafalaya could moderate flooding both places.
What if Mississippi's politicians got fired up and got back in the flood trading game? And worked a deal to speed the floods to the sea - all the way to the sea?
Kelley Williams, Chair – Bigger Pie Forum
Thursday, June 9, 2016
Kelly Williams: Corps building bigger floods
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14 comments:
Excellent article. John Barry's book Rising Tide should be required reading for everyone in Mississippi and Louisiana. It's a comprehensive study of Mississippi River flooding, specifically the 1927 flood and its lasting engineering, political and social impacts on the US. Reading this book on iPad while referring to google earth satellite imagery was amazing.
Engineers from Eads on down have been arguing about how to tame the mighty Mississippi for almost a century. Tributaries versus levees.
The solutions are not nearly as easy as this guy states because...well...weather. Nobody can predict weather.
So to claim one way is better than another is way too simplistic an approach...as proven by time.
@12:00. You just don't seem to understand! Let me xplne it to you......
Kelly Williams and Bigger Pie Forum know all the answers to any questions. Never any doubt.
Their solutions are always as easy as they state - because their logic is the only logic.
I truly admire Mr. Williams - always have. But, when he (or his ghost writers) get on a subject, they make it very simple. Understand them. Understand what they say. Accept no other version as being reasonable. Case settled.
The Mississippi River and its handling is one of the most interesting projects in our country's history. And granted, it has been mishandled many times over the past century and a half - more often than not because of political influence taking precedence over engineering analysis. But the differing engineering opinions as to how to tame this massive body of everchanging water are as varied as the political positions. Too bad Bigger Pie has not just gone to DC, explained to all the folks up there how simple the answer is if they would just listen to the folks that have the answers. Would have saved our country untold millions of dollars and allieved our sufferings.
P.S. You have to understand, though - Bigger Pie is an advertiser. Therefore, their opinion always gets postings.
Mother Nature has a little something to teach them.
Have you ever tried to pour two gallons of water in a one gallon bucket?
When you have no idea on how much water you can expect it is very hard to control it.
The problem with increasing flow down the Atchafalaya at the Old River Control Structure is that the Mississippi River would prefer to take the shorter route to the sea. In other words, the Mississippi River could decide that it would rather the bulk of its water down the Atchafalaya. This would devastate Morgan City and all of the petroleum industry. It would also destroy all the cities along the lower Mississippi, i.e., Baton Rouge and New Orleans. So be careful what you wish for. More flow down the Atchafalaya could create an epic disaster that would essentially destroy south Louisiana.
The notion that we can't predict Mother Nature is not exactly true.
We have a long record of her worst and usual and nicest behaviors so we should be able to be prepared to react to what Mother Nature does.
9:39 pm, are you saying that there is no way to improve the Old River Control structure or create other controls before the water reaches that control structure?
I have the sense that competing interests have long battled for dominancy on this issue rather than co-operated to solve the problems.
7:37, improving the river has not ever been the main objective. Finding a way to funnel tax payers money into a few politicians and their friend's pocket is the main objective.
The MS River does what it wants. Always has, always will. The more you try and channel it, the worse the floods will be. All of this channelization is killing the ecosystems from the South Delta to the Louisiana Marsh. Kingfish, I'm glad you're bringing this up. I have a piece of recreational land "behind the levee" that has been underwater pretty much since Thanksgiving. The big floods are happening more and more frequently and their severity is much worse. Something needs to be addressed and not by the Corps of Engineers. That's the dumbest bunch of people in contracting.
"Elam's book documented that cut offs worked."
We need to remember that there can be ripple effects to these efforts.
One of the negative consequences associated with the cut offs are the head cuts that are continuing to work their way up the tributary streams that flow into the MS River. These head cuts are continuing to widen & deepen streams for many miles upstream of their confluence with the MS, causing erosion of private land, and increased maintenance costs on bridges / roadways crossing these streams. Highway 33 bridge over the Homochitto River for instance is some 30 miles upstream of the MS. That bridge has been lengthened in the past and just recently had to be lengthened again. Not to mention the untold number of acres of land along these tributaries that have been gobbled up by this phenomenon.
One has to wonder, were we aware of these consequences in the '40's and chose to move ahead with the cutoff's or was this a surprise? Similarly, what are the consequences of sending more flow down the Atchafalaya that we're not aware of?
Kelly's work on the Kemper plant have been heroic. Everyone in the MS Power footprint should be very grateful.
@1:47 - yes Kelly, Ashby and all others that are heavily invested in natural gas should be grateful for Kelly's work. Let's forget that our tax dollars established his 'Bigger Pie' and that he is using that forum arguing against the use of tax dollars for private purposes. Minor detail.
"It would also destroy all the cities along the lower Mississippi, i.e., Baton Rouge and New Orleans."
9:39 - Are you suggesting that destroying Baton Rouge and all the associate corn dogs and possums would be a bad thing?
To the New Orleans native posting,
One has to wonder what would happen if we had let nature take it's "course."
One has to wonder what would happen if the Feds would have forced those New Orleans businessmen to reimburse (like they promised) those poor people they chose to flood in order to save their fair (investment) city.
One has to wonder what the benefit would be for all of the contaminated sediment to move further west in the Gulf, after being more filtered through the Atchafalaya.
One has to wonder how much taxpayer money would be saved by not maintaining the current broken system. Morganza?
One has to wonder why someone would talk about the Hwy 33 bridge as some sort of confirmation of cuts on the MS River causing damage, without any respect for natural erosion, much less the channel cutting and straightening of the Homochitto (Abernathy Channel, et al) and the scour associated with artificially altering the river course. Of course the Hwy 33 bridge collapsed during a flood in the 70's, it wasn't just lengthened. It had to be completely rebuilt.
I must respectfully disagree with Mr. Williams. The problem is allowing the river to go the the Atchafalaya Basin would be an economic disaster for the entire country, not just South Louisiana. Much of the nation depends on the port of New Orleans. How many refineries use that port? Again, it would be a disaster. 9:39 nailed it.
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