shaunmccarron29

How are levees designed and constructed?

There are thousands of miles of levees along the rivers and coastal areas of the United States, and the vast majority of levees are made mainly of earth or soil. Since soil is not waterproof, most levees will leak or seep some water. Such leakage is normal, and engineers control it in various ways. One way is to install an internal drainage system that intercepts and removes the seepage. Another way is to reinforce the soil with concrete walls or sheet pile walls made of steel. It is also common to install clay or cement grout within the levee to reduce seepage. Usually, more than one of these design measures is employed within a levee system. The levee system in New Orleans contains all of these design types.

What causes a levee to fail?

Most levee failures can be attributed to one or more mechanisms.

#1 Sideways hydrostatic pressure, which essentially “pushes over” the levee from the high water side. This usually means that the levee is not massive enough.

#2 Seepage of water through or beneath the levee, which leads to “erosion from the inside out.” Such failures usually mean that the levee was not water resistant enough.

#3 This type of failure is known as overtopping, during which waves splash over the top of the levee and erode them from the outside inwardly.
Water in the river raises higher than the crown of the levee. The water flows over the crown and down the land side of the levee, eroding the levee from the back side.

#4 Surface erosion. During high water when the river water is against the levee, waves generated by wind will erode the water-side of the levee.

#5 Shear failure (slope instability) of the levee. Manifested as large slabs of the levee sides sliding down the side of the levee during or immediately after high-water. Many days of high water will saturate the surface layers of the levee (by phreatic water movement) making them heavier than the underlying layers. The heavier surface layers lose cohesion with the lower layers, resulting in the surface layer sliding down the slope of the levee. In older levees constructed of sand the entire levee can become saturated during a flood resulting in total collapse of the levee.

#6 Piping and underseepage. During a flood the water column exerts a weight upon the levee sides and adjacent floodplain that pushes water into any holes or cracks in the levee structure. If the water reaches the landside of the levee it will flow from the levee and carry levee material with it, resulting in the levee eroding from the inside out. Flood water flows through permeable soil material that underlies the levee. The water arises to the surface near the landside base of the levee in what is termed a ”boil”. Again, the water is flowing, so it is carrying levee foundation material out from under the levee.


In some sections of New Orleans the levees are underlain by weak soils that are slowly compressing or sinking (organic silts). In some areas the city is sinking as much as 5 mm per year, which equates to about 2 inches in 10 years. To complicate matters, the sea level is rising globally, in the range of 2-4 mm per year; that means the city is losing an additional inch, with a water level rise of about 3 inches in 10 years. It is clear that any intermediate to long-term solution must take into account this rise of the water levels. Extending the prediction to 100 years, for example, means a rise in the water level of about 3 feet if current rates continue.

Hope that helps. If you feel any of the above is not factual, research the specific matter yourself, and then post your findings. This is how we learn.

Have a good 1

Can you tell me exactly where to find these? I am not sure if you can private message me. I joined this board days ago strictly to engage in the flood board.

I made It, I think I know what it is, Thanks Julie

This is a map that shows who will be underwater and who wont. 1 meter = 3.280 Feet For those who mite need this information to properly interpurt the following link:


Water Rise Map

Yesterday East of Baton Rouge we saw another World Record, 62.4 Feet at Red River. Flood Stage ( I hope we all know what that means by now, if not please look it up) is 48 feet. 14.4 Feet over, wow who would have thought.

Current Flow Rate? ANYONE? -999 is not the flow rate do whoever posted a link which had data from the last 2 weeks with the flow rate reading -999. That is an error message. Please GOOGLE flow rate, and you will understand that -999 = NO READING

You think the pressure exerted by the river will make the level stronger? Is that what you are saying?

god help us, you, if that is what you are saying.

Yah a Smart person, you are not missing anything, the media being released is inaccurate, so of course if the data you are given is inaccurate, you will never get the result they predict.

I HAVE SPENT DAYS AND DAYS ON THE CURRENT STATUS OF THE MISSISSIPPI RIVER, AND THE LEVEE CONTROL SYSTEM. READ THIS IS IF YOU WANT TO KNOW WHAT SEEMS TO BE THE UNDENIABLE TRUTH.
The levee system was never DESIGNED for THE present scenario. The flood of 1927 (with a flow rate of 2,34KcFs. 2.34 Million Cubic Feet of Water) was the catalyst to create a system that would protect cities built near or around the banks of the river. Unfortunately the Corp design of the levee program was created to protect cities in the event of extreme rain full, adding volume to the river. THE CURRENT SITUATION, is a combination of added water created by the melting snow and ice of the upper Midwest, along with rain, and now more rain in the next day or to. This will create great stress well over the systems capacity. In other words the basic design of the levee system is inherently flawed. With the flow rate last reported in Vicksburg, MS to be 2.72kcFs or 2.72 Million Cubic Feet, THE Highest EVER on RECORD, and the MAXIMUM Flow Rate Ceiling of New Orleans being 1.25 KcFS (1.25 Million Cubic feet of water). Calculations show that the rivers Flow Rate could possibly reach or exceed 2.72KcFs near, at, or before the port of New Orleans, exceeding the systems max flow rate by 1.47KcFs (1.47 Million cFs). The NORMAL Flow rate of the Mississippi passing through the port of New Orleans is 450,000cFs. The equation I created did not have a variable for added Rain, including run off crated by storms affecting the river. The latest Weather shows that contrary to prior predictions, the lower Midwest and Mississippi river area north of Louisiana WILL BE AFFECTED BY RAIN STORMS, CREATING INTENSE RAIN WHICH WILL ADD TO THE RIVERS VOLUME AND ULTIMATELY THE FLOW RATE. (Increase of ??? KcFs)
DO NOT BELIEVE THE NEWS, THEY ARE NOT REPORTING ACCURATE NOR UP TO DATE INFORMATION. IF YOU GO TO WEATHER.GOV you will SEE THAT THE CITY OF NEW ORLEANS IS IN A FLOOD WARNING, why does the news fail to report that? I hope I have given a clearer picture of exactly what we are facing, but there is one more thing. Two Concerns that could compromise New Orleans and Baton Rouge. The first one, which the NEWS has focused on because it is not important and the data they are reporting on gives the illusion that the problem is diminishing. 1) Height of water in the River. The news has given us the perception that this is the only concern we have to focus on. The Levee system protects uo until 20 feet. In this scenario, the river would become too full of water, rise, and flow over the man made levee, thus flooding the area no longer being protected. This scenario even if it becomes reality, seems to be far less cataclysmic than the 2nd Scenario. The second scenario has a much greater chance of becoming reality. For the second scenario please watch the short clip attached to this message. You will see that what the real danger lies in the fact that with the Flow Rate being so high for an extended period of time (weeks maybe months), Erosion of the levee system is inevitable. The implications of such failure would be cataclysmic rendering the city of New Orleans inoperable due to the fact that the already below see level area will be inundated with 10 to 20+ feet of water for an extended period of time. LISTEN PEOPLE, THERE IS ONLY ONE IMPORTANT PIECE OF DATA THAT UP UNTIL A WEEK AND HALF AGO WAS BEING REPORTED. THAT IS THE FLOW RATE. FOR SOME REASON ALL FLOW RATE SENSORS FROM THE MOUTH OF THE RIVER AND TWO STATES ABOVE ARE NO LONGER REPORTING THE FLOW RATE. We do not know why. ANY BREACH IN THE LEVEE SYSTEM WOULD BEING FLOODING THE CITY INSTANTLY. MAKING THE AREA A HIGH RISK TERRORIST ATTACH AREA.
Do you have speakers to watch a 45 sec CLIP that illustrates just how the levee's will fail as described in the 2nd Scenario? PLEASE WATCH IT.
Short Clip on Levee Failure
After watching the clip, it would make sense as to why the Corp has not been releasing the flow rates. I do not know what, if anything can be done, the short Video shows a great solution to replace the current flawed levee protection, but design and implementation of such would take years to fully develop. We have days. :confused: :confused: :moon: :moon: :moon: