Playing Politics with Morganza?

Took a drive up to the Old River Control Structure and the Morganza Spillway on the 12th of May. I was curious about what is keeping the Corps from opening the spillway until the flow hits 1.5 M CFS. One reason would be that until the river gets to that level, the water is not high enough for the spillway to work. I found that the water is high enough, so that we have to think about the politics.

While the Corps was able to get development easements as well as flowage  easements over most of the floodway, it is not clear that these have been enforced. The floodway also endangers Morgan City, which sits at the end of the Atchafalaya river, were the floodway necks down and the water has to flow out into the gulf through a main and minor branch of the river. (For those who are not local, tt is pronounced A CHAF A LIE A – short As.) The Corps trigger point is 1.5 million CFS at Red River Landing, just above the control structure, not the water heights downstream. How that flow corresponds to downstream heights depends on a lot of factors that change through time. The Corps has not publically addressed why it is sticking to the 1.5 MCFS, which was determined when the structures were built. It might have been the right number then, but now it results in very (record) high water downstream – that, or the flow is actually higher and the Corps have not figured it out.

The water level is below the levee tops, but it is well up the side of the levees. The projected crests before Morganza will be opened is pretty close to the tops of the levees. This puts a lot of pressure on the levees and pushes a lot of water under the levees. This water flows through sand boils, which are old stream beds which were covered when the levees were built. The water also flows through the saturated ground. The river is deep in many places and the water spreads out through the soil for a long distance. The longer the water level is high, the more water the clay in the levee absorbs, which weakens the levee. Clay levees do not melt away as did the sand levees on the middle Mississippi which broke during the 1993 flood. But when they develop a crack (crevasse), it erodes quickly and is difficult to plug during high water. In New Orleans, most of the city is below sea level and trapped within flood control levees. A levee break could rapidly put enough water into the city to flood many areas as deep as Katrina, and at least as fast. It would be worse because the water would be flowing through the high ground that was not flooded during Katrina. This might be the French Quarter, or the Ochsner medical center, or other high value areas that escaped Katrina damage.

The advantage to the Corps in putting these areas at unnecessary risk is that it will mute criticism when the spillway is opened and floodway is flooded, displacing people and destroying crops, and perhaps flooding Morgan City. Ironically, it is not a tradeoff – as the Corp’s maps show, if the spillway is not opened, it will be overtopped, as will other levees allowing water into the floodway. If the Corps opened all the relief valves early, protecting the levees downstream in Baton Rouge and New Orleans, it would be accused of not needing to open the spillway – unless the Corps creates a threat downstream, no one in the floodway would accept that there would have been a threat. (I have discussed this in my smallpox paper – politically, you do not want to roll out the smallpox vaccine until there are enough deaths to really scare people. Then no one will second guess you when there are serious vaccine complications. Do it early, stop the outbreak, and all people will see are the complications.)

The down side to the “scare them downstream strategy” (and the smallpox slow reaction strategy) is that if you guess wrong, it is catastrophic. The politicians in Baton Rouge and New Orleans are reassuring the population that the levees are perfect and that there is no risk. This means no evacuations, no thinking about what you would do if there was a break. Lower Mississippi levees are much better than hurricane levees, and much less susceptible to failure. Among other reasons, they are maintained by the Corps, while New Orleans levees were (not) maintained by the local levee boards. But there are probably 200 miles of levees between the Old River Control Structure and New Orleans. It is hard to assure that every mile is perfect. It is also impossible to keep materials and crews to plug a leak along the whole area. It would take a lot of time to get folks in place to repair a break, enough time to do real damage, and perhaps long enough for the levee to break down to the point where it cannot be repaired during high water.

An additional downside is the uncertainty for the people in the spillway. The Corps’ policy of only announcing a decision to open the spillway at the last minute leaves persons in the spillway uncertain whether they will need to evacuate. and when they need to be gone. The Corps predicted the record crests in Baton Rouge and New Orleans weeks ago. If the policy was to prevent levees downstream from being subjected to dangerous loads, the Corps could have announced that the spillway would be opened early in May. This would have given more evacuation time and would also have saved Baton Rouge and New Orleans from being exposed to unnecessary catastrophic risk.  It would also have allowed the gradual fill time necessary to protect wildlife without extending the high risk levels downstream.


NAS Climate Change Project

Convened by the National Research Council in response to a request from Congress (P.L. 110-161), America’s Climate Choices is a suite of five coordinated activities designed to study the serious and sweeping issues associated with global climate change, including the science and technology challenges involved, and to provide advice on the most effective steps and most promising strategies that can be taken to respond.

NAS Climate Change Project – original link

America’s Climate Choices

Advancing the Science of Climate Change

Limiting the Magnitude of Future Climate Change

Adapting to the Impacts of Climate Change

Informing an Effective Response to Climate Change


Climate Change and Polar Ecosystems

“The polar regions are experiencing rapid changes in climate. These changes are causing observable ecological impacts of various types and degrees of severity at all ecosystem levels, including society. Even larger changes and more significant impacts are anticipated. As species respond to changing environments over time, their interactions with the physical world and other organisms can also change. This chain of interactions can trigger cascades of impacts throughout entire ecosystems. Evaluating the interrelated physical, chemical, biological, and societal components of polar ecosystems is essential to understanding their vulnerability and resilience to climate forcing.”

Frontiers in Understanding Climate Change and Polar Ecosystems: Summary of a Workshop Committee for the Workshop on Frontiers in Understanding Climate Change and Polar Ecosystems; National Research Council, NAP (2011)

Ocean Rise in New York State

New York State Sea Level Rise Task Force, Report to the Legislature, December 2010.

“New York State’s extensive ocean coastline has places that we know, that we remember and that have shaped us in some way. The state’s coastline includes many notable locations—Montauk Point, Coney Island, Robert Moses State Park, Battery Park and the Hudson River’s shores from New York City to the federal dam at Troy. More than 60 percent of New Yorkers live in homes on or near these waterfront areas. Each shoreline area is unique and part of the essence of New York. But these places will change as sea level rises, and the differences will become more obvious as the sea continues to rise to levels never experienced by humans. A result of the world’s changing climate, a rising sea will alter more than just the coastline. The entire state will feel the effects as residents and a significant amount of the landscape are affected. These areas are diverse and interconnected and share New York’s rich agriculture, commercial, economic and environmental history and resources.

“The communities along New York State’s coastline, including their structures, their residents, their environment and the surrounding natural resources, are products of decisions made over the course of many years. These decisions shaped decades of investment, development and conservation. While the extent of the impacts to coastal communities from a rising sea are not fully known, even the most conservative projections make clear that there will be dramatic changes in this century. Thus, how coastal communities and our state address this collective challenge is important to today’s decision makers. The responses needed to protect communities from the threat posed by sea level rise will take time, and now that the challenges are better understood, government is obligated to protect its citizens while there is time to do so effectively. New York must focus on the smart use of limited resources to address the impacts associated with sea level rise.

The surge barrier alternative.

The Mississippi River and Tributaries Project

The Mississippi River and Tributaries Project:Controlling the Flow – a description of the operation of the lower Mississippi flood control plan. (accessed May 8, 2011)

This is the Army Corps of Engineers explanation of the Mississippi River flood control system and how it would be used to control a flood. It details the the use of the floodways and the river flow levels that will trigger their use. The key information for this flood is that up to 1,500,000 cubic feet per second (CFS) can be diverted into the Morganza/Achafalaya floodway. At the other end, 1,200,000 will flow out at through the Achafalaya River at Morgan City and 300,000 through the Wax Lake outlet of the Achafalaya river.

Mississippi River Flood of 2011

At least as to river heights, the Flood of 2011 may be second or third largest Mississippi River Flood in modern times. Total volume of the flood is hard to compare because the river and the tributaries are more constrained than in the past. Water in a leveed river will be much higher than in a river without levees where it can spread out horizontally.

Projected flood heights – NOAA – Corps’ Morganza floodway projections

Satellite images of the floods

Historical flood levels


Flood Risk from Opening the Morganza Floodway

Estimated Inundation Spring 2011 Flood Date: 06 May 2011 – Version 1, 06 May 2011 (EGIS Map ID No. 11-051-009)

Floodway into the Atchafalaya Basin saves New Orleans: Oliver Houck

“The Mississippi River is rising, the Army Corps of Engineers has just blown a controversial floodway levee north of Cairo, Ill., and the surge is coming downstream.

New Orleans will be safe, however, not because of its high river levees, which could be challenged if 2 million cubic feet per second swirl by at 8 miles an hour, chewing on the banks, even with a few feet of freeboard. Rather, the city is safe because of another floodway to the west, the Atchafalaya, that can take half the Mississippi’s highest flows and funnel them safely to the Gulf.

We also are safe because we have the rights to use this floodway, free and clear. This was not always the case. In fact, it became the case only after a long fight that ran for nearly 20 years over the Atchafalaya basin…

Read the rest of this editorial by Professor Oliver Houck of the Tulane Law School.

Mississippi Rising – The View from Baton Rouge

These pictures were taken on the levee at the intersection River Road and Stadium Drive in Baton Rouge. The normal river channel is out near the barges. Flood stage (where the river would top the banks if there was no levee) is 35 feet.

6 May 2011 – River stage 37.7 feet

5 May 2011 – River Stage 37 Feet

Climate Change and the National Flood Insurance Program – 1991

FEMA, Projected Impact of Relative Sea Level Rise on the National Flood Insurance Program, October 1991.

This study of the impact of relative sea level rise on the National Flood Insurance Program was authorized by Congress and signed into law on November 3, 1989. The requirements of this study as specified by the legislation are as follows:

SEC. 5. Sea Level Rise Study

The Director of the Federal Emergency Management Agency shall conduct a study to determine the impact of relative sea level rise on the flood insurance rate maps. This study shall also project the economic losses associated with estimated sea level rise and aggregate such data for the United States as a whole and by region1. The Director shall report the results of this study to the Congress not later than one year after the date of enactment of this Act. Funds for such study shall be made available from amounts appropriated under section 1376(c) of the National Flood Insurance Act of 1968.

The Control of Nature – Morganza Spillway

John McPhee has written a fascinating history of the River Control Structure at Morganza. While it is not clear that the Mississippi still wants to go down the Atchafalaya, losing the River Control Structure in a flood would still be a catastrophe that could rival Katrina.

“Three hundred miles up the Mississippi River from its mouth—many parishes above New Orleans and well north of Baton Rouge—a navigation lock in the Mississippi’s right bank allows ships to drop out of the river. In evident defiance of nature, they descend as much as thirty-three feet, then go off to the west or south. This, to say the least, bespeaks a rare relationship between a river and adjacent terrain—any river, anywhere, let alone the third-ranking river on earth.”

Read more

Blowing the Mississippi Levee – 2011

Missouri’s TRO against the Corps to prevent the blowing of the levee on the Mississippi in May 2011: complaintanswer; and district court opinion (upheld by the circuit court – Missouri v. U.S. Army Corps of Engineers, 11-01937, U.S. Court of Appeals for the Eighth Circuit (St. Louis)., and review was denined by the Supreme Court.)

This same issue was litigated when the Corps modified the levee system at this point, and Missouri tried to block the work based on failing to consider earthquakes under the EIS:

Story v. Marsh, 732 F.2d 1375 (8th Cir. 1984) – More levee law

Joint Statement From Agriculture Secretary Tom Vilsack And FEMA Administrator Craig Fugate On The Opening Of The Birds Point-New Madrid Floodway In Central Missouri

Interesting that almost none of the media pays attention to the legal situation of folks in the Missouri floodway – they originally got the land with easements on it, or sold an easement to the feds later. The original purchasers got the land very cheaply, precisely because of the easements. With time, everyone forgets that every day they are on land is a gift, not an entitlement. Then when the floodway is used, congress comes in and bails them out as if they owned the land free and clear.

The worse problem is playing out over the decision to open the Morganza spillway in Louisiana. This has not been opened since 1973, and it is full of people who forgot that is a spillway. This then inhibits the corps in opening the spillway, which then increases the belief that it will never be opened. The Corps should be opening Morganza right now, rather than seeing how much stress the downstream levees can take. For example, the major prison in LA, Angola, is on a bend in the river. The projected crest is now higher than the levee at Angola, and the state is starting the process of evacuating a max security prison with more than 5,000 prisoners. That would not be necessary if Morganza was open. Baton Rouge is facing a crest 4 feet about the previous record, which may put some water over the levee on the Port Allen (west side) of the river, since those levees are a little lower. While 47.5 feet is below the level of the levees, it is enough to drive a lot of water under the levee. You can already see the water level in the drainage ditches near the levee going up, and sand boils are carrying water several thousand feet from the river into neighborhoods. If things are not as the Corps thinks they are with the levees, and a boil blows out like in Cairo, you could get a lot of flooding fast. The conventional wisdom in LA is that Mississippi river levees do not break, but that is only true until it isn’t. (They are built and maintained better than hurricane levees, but the Corps knows a lot less about the geology in south LA than it thinks.)

So, should we let people live and farm in spillways at all? My vote would be to make them wilderness, and to open them pretty regularly to keep the charged with silt and filled with wetlands.

This post will be updated as more information is available.