New Orleans is a very unique city, with it's own styles of music, cuisine and architecture. It has an extensive mix of both French and Spanish influence, and was America's port to the Caribbean and South America long before Miami became a major city.
New Orleans is located between Lake Pontchartrain to the north, and the Mississippi River to the south. The classic image of New Orleans is that of a steamboat on the Mississippi River:https://en.wikipedia.org/wiki/New_Orleans#/media/File:Hippolyte_Sebron_-_Bateaux_A_Vapeur_G%C3%A9ants_1853.jpg
This is a satellite image of New Orleans, between Lake Pontchartrain to the north and the winding Mississippi River going through the city:
https://en.wikipedia.org/wiki/New_Orleans#/media/File:Landsat_new_orleans_nfl.jpg
Here are the photos, from the Travel Photo Blog of North America, from the famed Bourbon Street in the French Quarter of New Orleans:
http://photos1.blogger.com/blogger/5492/3756/1600/dc_250982.jpg
http://photos1.blogger.com/blogger/5492/3756/1600/dc_250983.jpg
Have you ever noticed that cobblestones, or buildings made out of stones, are not seen in New Orleans? That is because it is built on the alluvial soil of the Mississippi Delta, which was carried there by water and so would not include stones.
New Orleans began on the higher ground where the French Quarter is located, this is the oldest area of the city. But human activity changed the hydrology of the area, causing the water table to drop and thus the land to settle. In some places, ground level gradually lowered by up to eight feet (more than two meters). This left most of the city below the level of Lake Pontchartrain and even further below the level of the Mississippi River.
The Mississippi River flows past New Orleans into the Gulf of Mexico, and Lake Pontchartrain is actually connected to the Gulf of Mexico. This means that it is not technically a lake because it's waters are salty. The side of New Orleans facing the Mississippi is traditionally considered as the "front of the town", while the side facing Lake Pontchartrain is the "back of the town".
This is the cross-section chart of the land elevation of New Orleans, with the higher Mississippi River to the left, and the lower Lake Pontchartrain to the right:
https://en.wikipedia.org/wiki/New_Orleans#/media/File:New_Orleans_Levee_System.svg
The dilemma of New Orleans is that the system of levees which keep the waters of the lake and the river out, also hold rainwater in. With the city being below the level of the surrounding waters, there is no natural outlet for the water from rainfall. New Orleans has constructed an extensive network of pumping stations and drainage canals to empty water within the city into Lake Pontchartrain.
There are several canals, with levees on either side, crossing the city with water levels above the level of the surrounding land. The major canals are the London Avenue Canal, the Orleans Avenue Canal and, the 17th Street Canal. Aside from these open canals, there are also closed channels and sewers to evacuate rainwater. There is also the Industrial Canal, but that is a navigable waterway with locks that connects Lake Pontchartrain to the Mississippi River.
This photo shows how the level of the water in the canals, the same as that in Lake Pontchartrain to which they connect, is higher than the level of the land which they protect. A levee is a bank of earth that holds back water, while a flood wall is an actual wall:
https://en.wikipedia.org/wiki/17th_Street_Canal#/media/File:MetOutletCanalDogwalkerBreechBkgrd.jpg
Here is excess water being pumped, by a pumping station, into a drainage canal:
https://en.wikipedia.org/wiki/17th_Street_Canal#/media/File:17th_Street_Canal,_in_New_Orleans.jpg
The pumping stations pump water into the canals, which then empty it into Lake Pontchartrain. But if the level of the lake were to suddenly rise, it would cause water to rush into the canals, putting added pressure on the levees.
At the end of August, 2005, I had just started this blog writing a month before. The massive Hurricane Katrina was approaching New Orleans from the direction of the Gulf of Mexico. A hurricane is actually an extreme low pressure center, with the tremendous winds rushing in from higher pressure areas, the circular motion is the result of momentum of the earth's rotation.
As the hurricane passes over water, it means less atmospheric pressure. This causes the water level to rise under a hurricane, and this is referred to as a "storm surge". As the hurricane passed over the coast, the water from it's storm surge rushed into Lake Pontchartrain, which is connected to the Gulf of Mexico. This caused the water level in the lake to rise suddenly, and water to rush into the outfall canals of New Orleans.
The barriers protecting New Orleans along the shore of Lake Pontchartrain held the water back, as planned. But along the canals in the city, with water levels higher then the surrounding ground and under greater pressure because of the water rushing in from the lake, the walls of the canals breached in dozens of places. The levees of the Orleans Avenue Canal did not breach but the 17th Street Canal wall gave way on the New Orleans side, and the levees of the London Avenue Canal were breached on both sides. In some areas, water came up through the storm drains.
Most of the city was flooded, but the high ground of the oldest part of the city was safe:
https://en.wikipedia.org/wiki/New_Orleans#/media/File:Navy-FloodedNewOrleans.jpg
https://en.wikipedia.org/wiki/Drainage_in_New_Orleans#/media/File:SCarrollton1Floor.jpg
It seems that when the levees along the canals were constructed, the underlying alluvial soil of the Mississippi Delta was presumed to be more sturdy than it really was. Many of the breaches in the canal levees occurred where the water level had not even reached the tops of the levees.
Nearly 1,500 people were killed. The response the the disaster was the turning point in the presidency of George W. Bush. Vast numbers of people went off into exile in other cities, particularly Houston, where they were not always welcomed
Conspiracy theories, mostly based on economic class, ran wild. Thousands of refugees were taken into the New Orleans Superdome stadium. Tabloids were filled with stories of rampant rape, robbery and, assault taking place, which mostly turned out not to be true.
Then there was the story that the government had spared no expense to reinforce the levees along neighborhoods where rich people lived, but hadn't bothered to take the same precautions in poorer neighborhoods.
The next story was that, when the flooding began, the government had actually dynamited the levees in poorer neighborhoods in order to divert the water away from the neighborhoods where rich people lived.
After the flood, there was actually plenty of food and supplies for everybody but, as we might expect, the government was making sure that wealthy people were taken care of first.
Finally, the story emerged that the government had purposely built the levees so that they would not withstand the storm surge of the hurricane which would inevitably come because the poorer neighborhoods of New Orleans were too much of a drain on the economy and the government just wanted to be rid of them.
There was another story, which may have some truth to it, that there was the city's fleet of school buses, which could have ferried thousands of people to safety, but by the time permission could be obtained to use the buses, it was too late because they were underwater.
In still another story a large group of refugees, led by some New Orleans Police officers, managed to walk to a neighboring town that had not been flooded. But, as they were going to cross into that town, police from the town pointed their guns at the group, including their fellow officers, and insisted that they not enter the town. The town feared being inundated by "criminal elements" from the city.
But this isn't just any city here, this is New Orleans.
I remember one year when the local pro football team, the New Orleans Saints, was doing so poorly that fans of the team wore paper bags over their heads, because they were so ashamed of their team, which they nicknamed the "Aints", instead of the Saints.
They could not imagine that the team would one day come back to win the Super Bowl (the U.S. national championship), in the 2009 season.
Sure enough, this very special city has today come back from the mega-disaster, and is now better than ever. The spirit of New Orleans has proven to be stronger than Hurricane Katrina.
Just looking at the map of New Orleans, I notice a solution which would prevent this from happening again.
The north-south blue lines, leading to Lake Pontchartrain in the north, are the canals which drain rainwater that is pumped into them from the city's numerous pumping stations. The drainage canals do not connect to the Mississippi River, to the south. Only the navigable Industrial Canal, to the right, links to both the Mississippi River and Lake Pontchartrain. The Industrial Canal has the lock system to accommodate the up to 6 meter (20 ft) difference in water levels between the river and the lake. The storm surge from Hurricane Katrina caused water to rush from the lake into the canals, breaching the levees of the canals:
https://www.google.com/maps/@29.9905854,-90.1024178,13z
Here is another map of the three main drainage canals of New Orleans:
https://en.wikipedia.org/wiki/New_Orleans_Outfall_Canals#/media/File:Outfall_canals_map.jpg
What if we extended the drainage canals to the Mississippi River, just as the Industrial Canal does? If a door was put at the ends of each canal, as was done where the canals meet Lake Pontchartrain following Hurricane Katrina, we could choose whether the water that is pumped into the canals would empty into the river or into the lake. The level of the water in the Mississippi River is higher than that in Lake Pontchartrain, because the Mississippi must flow downward into the Gulf of Mexico and the water in Lake Pontchartrain is ordinarily at the same level as that of the Gulf, and this would mean that the height of the levees and flood walls would have to be increased to that of the usual level of the Mississippi River, but not to the higher level of the Mississippi when it floods because the doors to the river would not be open at that time.
Under this system, if there was the danger of a storm surge into Lake Pontchartrain again, the doors between the drainage canals and the lake could be closed to block the storm surge waters from flowing into the canals, and the doors of the canals to the Mississippi River could be opened, so that the excess water that is pumped into the canals would empty into the Mississippi River.
Before Hurricane Katrina, the main concern with flooding in New Orleans was from the Mississippi River side, not the Lake Pontchartrain side. The Mississippi River is indeed notorious for flooding. I remember following the news of the disastrous floods of 1993.
But floods on the Mississippi tend to happen in spring, brought about by sudden snow melt. The chance that the level of water in the river will be high at the same time that there is a storm surge in Lake Pontchartrain is, while not impossible, extremely remote. The storm surge of a hurricane does not affect the level of water in the Mississippi River, where New Orleans is located, because the river is flowing in the opposite direction, toward the Gulf of Mexico.
The doors at the end of each canal could be opened or closed so that drainage water would flow into whichever was at the lowest water level. During storm surges, the doors to Lake Pontchartrain would be closed and the doors to the Mississippi River would be opened. The storm surge would raise the water level in the lake, but not in the river. The flow of the Mississippi would shield New Orleans from the storm surge. When the hurricane was over, and the water level dropped back below that of the Mississippi as it is normally, then the doors to the river could be closed and the doors to the lake reopened.
The same extension and doors would also, of course, have to be included in the storm drain system through which water entered some areas of New Orleans during Hurricane Katrina. This also applies to any covered drainage channels that we do not see on the map.
With the powerful pumps available nowadays, it is not really even necessary for the drainage canals to empty directly into either the Mississippi River or Lake Pontchartrain. If available land could be found, excess water could flow through the drainage canals to a large collection basin, and from there into either the lake or the river. Safety channels could be included so that, if the basin overflowed, water would flow through this channel into either the lake or the river, rather than flooding the land in the city.
In the first of the following scenes, we see the flood wall in the background along the 17th Street Canal where a major breach took place in 2005. A pumping station has since been built on the site, and the cars are in the parking lot of the pumping station.
There are multiple scenes following. To see the scenes, after the first one, you must first click the up arrow, ^, before you can move on to the next scene by clicking the right or forward arrow, >. After clicking the up arrow, ^, you can then hide the previews of successive scenes, if you wish.
https://www.google.com/maps/@30.0177549,-90.1203656,3a,90y,257.07h,87.7t/data=!3m7!1e1!3m5!1s6KuOL7zyO_tOVQw5LzZg2g!2e0!6s%2F%2Fgeo1.ggpht.com%2Fcbk%3Fpanoid%3D6KuOL7zyO_tOVQw5LzZg2g%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D15.753598%26pitch%3D0!7i13312!8i6656
The first of the following images, taken on Bourbon Street in the French Quarter, is from the same perspective as the following image on the travel photo blog of North America.
http://photos1.blogger.com/blogger/5492/3756/1600/dc_250982.jpg
The French Quarter is the oldest part of New Orleans, is on the highest ground, and did not flood during Hurricane Katrina. The rest of the images includes St. Louis Cathedral and Jackson Square. Most of the buildings are actually of Spanish construction, after the earlier French buildings had been destroyed in a fire, and before New Orleans came under control of the United States in 1803:
https://www.google.com/maps/@29.9591281,-90.0651961,3a,75y,201.45h,82.03t/data=!3m7!1e1!3m5!1sy_GwFX_eeayBSwotP-ygXg!2e0!6s%2F%2Fgeo1.ggpht.com%2Fcbk%3Fpanoid%3Dy_GwFX_eeayBSwotP-ygXg%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D145.93224%26pitch%3D0!7i13312!8i6656
Here are some images of downtown New Orleans, starting outside the Superdome:
https://www.google.com/maps/@29.9514916,-90.0794899,3a,75y,88.68t/data=!3m8!1e1!3m6!1s-wiLb3nlvFmo%2FVCTeDNi8I9I%2FAAAAAAAAUdM%2FapJkvouDwM48lNXCuTckgcF3grKFvhilg!2e4!3e11!6s%2F%2Flh6.googleusercontent.com%2F-wiLb3nlvFmo%2FVCTeDNi8I9I%2FAAAAAAAAUdM%2FapJkvouDwM48lNXCuTckgcF3grKFvhilg%2Fw203-h101-n-k-no%2F!7i7272!8i3636
This photo shows how the level of the water in the canals, the same as that in Lake Pontchartrain to which they connect, is higher than the level of the land which they protect. A levee is a bank of earth that holds back water, while a flood wall is an actual wall:
https://en.wikipedia.org/wiki/17th_Street_Canal#/media/File:MetOutletCanalDogwalkerBreechBkgrd.jpg
Here is excess water being pumped, by a pumping station, into a drainage canal:
https://en.wikipedia.org/wiki/17th_Street_Canal#/media/File:17th_Street_Canal,_in_New_Orleans.jpg
The pumping stations pump water into the canals, which then empty it into Lake Pontchartrain. But if the level of the lake were to suddenly rise, it would cause water to rush into the canals, putting added pressure on the levees.
At the end of August, 2005, I had just started this blog writing a month before. The massive Hurricane Katrina was approaching New Orleans from the direction of the Gulf of Mexico. A hurricane is actually an extreme low pressure center, with the tremendous winds rushing in from higher pressure areas, the circular motion is the result of momentum of the earth's rotation.
As the hurricane passes over water, it means less atmospheric pressure. This causes the water level to rise under a hurricane, and this is referred to as a "storm surge". As the hurricane passed over the coast, the water from it's storm surge rushed into Lake Pontchartrain, which is connected to the Gulf of Mexico. This caused the water level in the lake to rise suddenly, and water to rush into the outfall canals of New Orleans.
The barriers protecting New Orleans along the shore of Lake Pontchartrain held the water back, as planned. But along the canals in the city, with water levels higher then the surrounding ground and under greater pressure because of the water rushing in from the lake, the walls of the canals breached in dozens of places. The levees of the Orleans Avenue Canal did not breach but the 17th Street Canal wall gave way on the New Orleans side, and the levees of the London Avenue Canal were breached on both sides. In some areas, water came up through the storm drains.
Most of the city was flooded, but the high ground of the oldest part of the city was safe:
https://en.wikipedia.org/wiki/New_Orleans#/media/File:Navy-FloodedNewOrleans.jpg
https://en.wikipedia.org/wiki/Drainage_in_New_Orleans#/media/File:SCarrollton1Floor.jpg
It seems that when the levees along the canals were constructed, the underlying alluvial soil of the Mississippi Delta was presumed to be more sturdy than it really was. Many of the breaches in the canal levees occurred where the water level had not even reached the tops of the levees.
Nearly 1,500 people were killed. The response the the disaster was the turning point in the presidency of George W. Bush. Vast numbers of people went off into exile in other cities, particularly Houston, where they were not always welcomed
Conspiracy theories, mostly based on economic class, ran wild. Thousands of refugees were taken into the New Orleans Superdome stadium. Tabloids were filled with stories of rampant rape, robbery and, assault taking place, which mostly turned out not to be true.
Then there was the story that the government had spared no expense to reinforce the levees along neighborhoods where rich people lived, but hadn't bothered to take the same precautions in poorer neighborhoods.
The next story was that, when the flooding began, the government had actually dynamited the levees in poorer neighborhoods in order to divert the water away from the neighborhoods where rich people lived.
After the flood, there was actually plenty of food and supplies for everybody but, as we might expect, the government was making sure that wealthy people were taken care of first.
Finally, the story emerged that the government had purposely built the levees so that they would not withstand the storm surge of the hurricane which would inevitably come because the poorer neighborhoods of New Orleans were too much of a drain on the economy and the government just wanted to be rid of them.
There was another story, which may have some truth to it, that there was the city's fleet of school buses, which could have ferried thousands of people to safety, but by the time permission could be obtained to use the buses, it was too late because they were underwater.
In still another story a large group of refugees, led by some New Orleans Police officers, managed to walk to a neighboring town that had not been flooded. But, as they were going to cross into that town, police from the town pointed their guns at the group, including their fellow officers, and insisted that they not enter the town. The town feared being inundated by "criminal elements" from the city.
But this isn't just any city here, this is New Orleans.
I remember one year when the local pro football team, the New Orleans Saints, was doing so poorly that fans of the team wore paper bags over their heads, because they were so ashamed of their team, which they nicknamed the "Aints", instead of the Saints.
They could not imagine that the team would one day come back to win the Super Bowl (the U.S. national championship), in the 2009 season.
Sure enough, this very special city has today come back from the mega-disaster, and is now better than ever. The spirit of New Orleans has proven to be stronger than Hurricane Katrina.
Just looking at the map of New Orleans, I notice a solution which would prevent this from happening again.
The north-south blue lines, leading to Lake Pontchartrain in the north, are the canals which drain rainwater that is pumped into them from the city's numerous pumping stations. The drainage canals do not connect to the Mississippi River, to the south. Only the navigable Industrial Canal, to the right, links to both the Mississippi River and Lake Pontchartrain. The Industrial Canal has the lock system to accommodate the up to 6 meter (20 ft) difference in water levels between the river and the lake. The storm surge from Hurricane Katrina caused water to rush from the lake into the canals, breaching the levees of the canals:
https://www.google.com/maps/@29.9905854,-90.1024178,13z
Here is another map of the three main drainage canals of New Orleans:
https://en.wikipedia.org/wiki/New_Orleans_Outfall_Canals#/media/File:Outfall_canals_map.jpg
What if we extended the drainage canals to the Mississippi River, just as the Industrial Canal does? If a door was put at the ends of each canal, as was done where the canals meet Lake Pontchartrain following Hurricane Katrina, we could choose whether the water that is pumped into the canals would empty into the river or into the lake. The level of the water in the Mississippi River is higher than that in Lake Pontchartrain, because the Mississippi must flow downward into the Gulf of Mexico and the water in Lake Pontchartrain is ordinarily at the same level as that of the Gulf, and this would mean that the height of the levees and flood walls would have to be increased to that of the usual level of the Mississippi River, but not to the higher level of the Mississippi when it floods because the doors to the river would not be open at that time.
These structures along the river in Niagara Falls house the doors that can shut off the flow of water from the river to the underground channels that deliver water to the hydropower plant. Image from Google Earth.
Under this system, if there was the danger of a storm surge into Lake Pontchartrain again, the doors between the drainage canals and the lake could be closed to block the storm surge waters from flowing into the canals, and the doors of the canals to the Mississippi River could be opened, so that the excess water that is pumped into the canals would empty into the Mississippi River.
Before Hurricane Katrina, the main concern with flooding in New Orleans was from the Mississippi River side, not the Lake Pontchartrain side. The Mississippi River is indeed notorious for flooding. I remember following the news of the disastrous floods of 1993.
But floods on the Mississippi tend to happen in spring, brought about by sudden snow melt. The chance that the level of water in the river will be high at the same time that there is a storm surge in Lake Pontchartrain is, while not impossible, extremely remote. The storm surge of a hurricane does not affect the level of water in the Mississippi River, where New Orleans is located, because the river is flowing in the opposite direction, toward the Gulf of Mexico.
The doors at the end of each canal could be opened or closed so that drainage water would flow into whichever was at the lowest water level. During storm surges, the doors to Lake Pontchartrain would be closed and the doors to the Mississippi River would be opened. The storm surge would raise the water level in the lake, but not in the river. The flow of the Mississippi would shield New Orleans from the storm surge. When the hurricane was over, and the water level dropped back below that of the Mississippi as it is normally, then the doors to the river could be closed and the doors to the lake reopened.
The same extension and doors would also, of course, have to be included in the storm drain system through which water entered some areas of New Orleans during Hurricane Katrina. This also applies to any covered drainage channels that we do not see on the map.
With the powerful pumps available nowadays, it is not really even necessary for the drainage canals to empty directly into either the Mississippi River or Lake Pontchartrain. If available land could be found, excess water could flow through the drainage canals to a large collection basin, and from there into either the lake or the river. Safety channels could be included so that, if the basin overflowed, water would flow through this channel into either the lake or the river, rather than flooding the land in the city.
In the first of the following scenes, we see the flood wall in the background along the 17th Street Canal where a major breach took place in 2005. A pumping station has since been built on the site, and the cars are in the parking lot of the pumping station.
There are multiple scenes following. To see the scenes, after the first one, you must first click the up arrow, ^, before you can move on to the next scene by clicking the right or forward arrow, >. After clicking the up arrow, ^, you can then hide the previews of successive scenes, if you wish.
https://www.google.com/maps/@30.0177549,-90.1203656,3a,90y,257.07h,87.7t/data=!3m7!1e1!3m5!1s6KuOL7zyO_tOVQw5LzZg2g!2e0!6s%2F%2Fgeo1.ggpht.com%2Fcbk%3Fpanoid%3D6KuOL7zyO_tOVQw5LzZg2g%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D15.753598%26pitch%3D0!7i13312!8i6656
The first of the following images, taken on Bourbon Street in the French Quarter, is from the same perspective as the following image on the travel photo blog of North America.
http://photos1.blogger.com/blogger/5492/3756/1600/dc_250982.jpg
The French Quarter is the oldest part of New Orleans, is on the highest ground, and did not flood during Hurricane Katrina. The rest of the images includes St. Louis Cathedral and Jackson Square. Most of the buildings are actually of Spanish construction, after the earlier French buildings had been destroyed in a fire, and before New Orleans came under control of the United States in 1803:
https://www.google.com/maps/@29.9591281,-90.0651961,3a,75y,201.45h,82.03t/data=!3m7!1e1!3m5!1sy_GwFX_eeayBSwotP-ygXg!2e0!6s%2F%2Fgeo1.ggpht.com%2Fcbk%3Fpanoid%3Dy_GwFX_eeayBSwotP-ygXg%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D145.93224%26pitch%3D0!7i13312!8i6656
Here are some images of downtown New Orleans, starting outside the Superdome:
https://www.google.com/maps/@29.9514916,-90.0794899,3a,75y,88.68t/data=!3m8!1e1!3m6!1s-wiLb3nlvFmo%2FVCTeDNi8I9I%2FAAAAAAAAUdM%2FapJkvouDwM48lNXCuTckgcF3grKFvhilg!2e4!3e11!6s%2F%2Flh6.googleusercontent.com%2F-wiLb3nlvFmo%2FVCTeDNi8I9I%2FAAAAAAAAUdM%2FapJkvouDwM48lNXCuTckgcF3grKFvhilg%2Fw203-h101-n-k-no%2F!7i7272!8i3636
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