I'm putting this in here because we're spending a lot of money rebuilding this city in a very traditional way. http://www.breitbart.com/news/2006/05/31/D8HV2TCO1.html New Orleans Sinking Faster Than Thought May 31 8:02 PM US/Eastern Email this story By SETH BORENSTEIN AP Science Writer WASHINGTON Everyone has known New Orleans is a sinking city. Now new research suggests parts of the city are sinking even faster than many scientists imagined _ more than an inch a year. That may explain some of the levee failures during Hurricane Katrina and it raises more worries about the future. The research, reported in the journal Nature, is based on new satellite radar data for the three years before Katrina struck in The data show that some areas are sinking four or five times faster than the rest of the city. And that, experts say, can be deadly. "My concern is the very low-lying areas," said lead author Tim Dixon, a University of Miami geophysicist. "I think those areas are death traps. I don't think those areas should be rebuilt." The blame for this phenomenon, called subsidence, includes overdevelopment, drainage and natural seismic shifts. For years, scientists figured the city on average was sinking about one-fifth of an inch a year based on 100 measurements of the region, Dixon said. The new data from 150,000 measurements taken from space finds that about 10 percent to 20 percent of the region had yearly subsidence in the inch-a-year range, he said. As the ground in those areas sinks, protection from levees also falls, scientists and engineers said. For example, the Mississippi River Gulf Outlet, built more than three decades ago, has sunk by more than 3 feet since its construction, Dixon said, explaining why water poured over the levee and part of it failed. "The people in St. Bernard got wiped out because the levee was too low," said co-author Roy Dokka, director of the Louisiana Spatial Center at Louisiana State University. "It's as simple as that." The subsidence "is making the land more vulnerable; it's also screwed up our ability to figure out where the land is," Dokka said. And it means some evacuation roads, hospitals and shelters are further below sea level than emergency planners thought. So when government officials talk of rebuilding levees to pre-Katrina levels, it may really still be several feet below what's needed, Dokka and others say. "Levees that are subsiding at a high rate are prone to failure," Dixon said. The federal government, especially the Army Corps of Engineers, hasn't taken the dramatic sinking into account in rebuilding plans, said University of Berkeley engineering professor Bob Bea, part of an independent National Academy of Sciences-Berkeley team that analyzed the levee failures during Katrina. "You have to change how you provide short- and long-term protection," said Bea, a former engineer in New Orleans. He said plans for concrete walls don't make sense because they sink and can't be easily added onto. In California, engineers are experimenting with lighter weight, reinforced foam-middle levee walls, he said. Dixon and his co-author Dokka disagree on the major causes of New Orleans' not-so-slow fall into the Gulf of Mexico. Dixon blames overdevelopment and drainage of marshlands, saying "all the problems are man-made; before people settled there in the 1700s, this area was at sea level." But Dokka said much of the sinking is due to natural seismic shifts that have little to do with construction. Dokka also thinks all is not completely lost. Smarter construction can buy New Orleans some time. "We've made the pact with the devil by moving down here," he said. "If we do things right, we probably can get another 100-200-300 years out of this area." The Army Corps of Engineers is adding extra height to earthen levees to compensate for sinking and is setting benchmark measurements of all levees for regular monitoring of how much they sink, corps spokesman Gene Pawlik said. "It's something post-Katrina, we're much more focused on," Pawlik said Wednesday. "It's certainly an engineering challenge."
This shouldn't be surprising since the whole Louisiana cost is sinking by about a 1,000 acres a year. The article cited some of the causes but another cause is the inability of the Mississippi to continue to build and maintain its delta due to the confining of it to one main channel and damming and locking.
it's surprising because apparently it's sinking faster than they thought. no one doubted it was sinking...everyone knew that. but an inch a year?
Nature will always win, this is so tough because the realist in me says to let it go, and not rebuild it. But my heart says bring it back. DD
i watched a thing on CNN yesterday about this....and they showed parts of town that haven't even begun to be touched yet. looks like ground zero. there are definitely areas of that town that shouldn't be rebuilt. areas that got pounded and are still sinking quickly. i can't imagine insuring property there.
There a large sections of the city that will not ever get rebuilt. No one is going to back loans for development in those areas. Another big hurricane this year might drive that point home to the unbelievers.
what's amazing is Katrina wasn't their worst case scenario. it wasn't a direct hit. the storm started turning before it made landfall. could have been far worse.
They could build a giant dome over the city and then let the whole thing sink. Then in several hundred years we would have the first city completely under the ocean. Sounds like a tourist destination to me.
As SC alludes, this isn't just about rebuilding NOLA, it's about rethinking the whole Mississippi Delta ecosystem and how we have directed the river to the deep waters of the gulf instead of letting the silt build up across the LA coastline. As for NOLA itself, there's no way this country cannot have a major port at the mouth of the Mississippi River. If you have a port, you have to have people who work there. If you have workers, you have to have people providing services for those workers. And this argument doesn't consider the historical and cultural importance of New Orleans and the delta, which are reasons enough to rebuild it... and it can be done. As more time goes on, I'm finding myself grateful for the incompetence and inattention of the current administration. 2 1/2 years from now, maybe we'll have an administration that is competent and sees the importance of the Delta and NOLA and sees beyond the immediate gratification of awarding contracts to donors. Maybe then we can do it right. Of course, between now and then, a lot of people continue to suffer and we probably end up with other areas in the same situation... Hurricane Season starts today.
totally agree. you have to have a port there. but you can build it much smarter. it's not just that the city is a port city that's the problem, though. it's that the city is in a bowl...surrounded by water pouring in on all sides. a really expensive solution would be to move NOLA/Port City X north...on the northern shore of the lake instead of leaving it there between a rock and a hard place. the problem, though, is that when solutions like that are presented they're deemed as insensitive. there's probably no one on the planet who is more sensitive to people's connection to their hometown than i am...but at some point, when you can't get insurance companies to issue policies...or banks to lend...you have to rethink it all. and when scientists are looking at it and calling it a death-trap...well...maybe that's another clue.
I don't think that's as huge a deal as you do. It will definitely have to be a govt/industry solution, but it could be done. The fact that Katrina happened can't be news to the insurance companies who certainly knew beforehand that the risk posed to NOLA by hurricanes was great, yet they continued to issue policies and banks continued to lend. Los Angeles seems to be doing OK with insurance companies and banks, yet we know... KNOW! that at some point a major earthquake is going to hit the city. When that happens it will make Katrina look like child's play. On the other hand, there's that Inconvenient Truth...if global warming is heading the direction independent scientists think, then that could change things dramatically. If we start having routine hits from major storms and multiple loss areas for insurance companies, it may put a damper on everything from New Jersey to Brownsville. All the more reason to have serious leadership in this country.
it's not just hurricanes, though. it's the fact that the entire city is sinking. they're losing acres of land each year to the gulf in louisiana. it doesn't take a hurricane...just a flood event poses nightmares when the water that surrounds you is situated higher than you are. there are entire areas of NOLA that aren't being touched. my guess is that has as much to do with insurance companies and banks as anything else. as i understand it, those are the areas that we're talking about here...the ones that are sinking faster than expected.
Max, I suspect we agree more than we think. For instance, when you say... and I say "we need to rethink the whole Delta ecosystem," we're both acknowledging that something more than just rebuilding NOLA within the city limits has to take place. If you allow the Delta to function anywhere close to what it should be doing naturally, then you draw a line from Lafayette to Baton Rouge to New Orleans (or perhaps Gulfport) and every community below that arc becomes unsustainable in its current form or at least greatly changed. That may be insensitive and that will alter many people's lives, but otherwise, Baton Rouge will eventually be a coastal city. Again, this problem is crying for leadership and vision.
From my experience in NOLA it seems like most of the people there want to rebuild it as is but being away from it I'm not sure if that is practical or even possible. Whether NOLA gets rebuilt as is or not the main thing I'm concerned about is that the people there get compensated and aren't forced to start over from nothing. If its going to costs tens of billions to rebuild a levy system and raise up houses in NOLA it might be better to take that money and see that the people get resettled with enough capital to make a new start. I agree NOLA's a great city and it would suck to see it go or be reduced to a tourists attraction like Colonial Williamsburg but the practicality of maintaining a sinking city below sea level has to be considered. I think the same practicality should be considered for cities in California, Florida, Arizona and Nevada and I'm for insurerers taking steps to not insure or raise premiums in areas that are so naturally prone to disasters. By subsidizing development in disaster areas we're only subsidizing the likelyhood that when a disaster hits it will be that much more devestating and expensive than if the development hadn't happened at all.
