After a $14B Upgrade, New Orleans’ Levees Are Sinking

I'm not an expert, but intuitively, I'd think that sea level rise would contribute to ground subsidence.

A lot of the current problem in New Orleans is that it's built on deep layers of silt which are slowly compacting. And channelizing the Mississippi has resulted in loss of protective barriers offshore because the silt now goes right out the end of the channel into deep water. Bonus the bedrock itself is slowly tilting sinking towards the gulf.

What the place needs is about three meters of compacted fill under the whole city. ALA Galveston TX and Downtown Chicago.

This says three main factors: 1.)sediment flow changes - we changed flow of Mississippi River to benefit a lot of upstream communities (for flood control/farming/maintaining river boundaries against nature's desire) - continuing to do so robs Louisiana of land mass 2.) subsidence - pumping out water aquifers and extracting oil (without replacing fluids) cause land levels to sink 3.) sea level rise

https://www.factcheck.org/2017/03/land-loss-in-louisiana/ All three together paint a pretty grim picture of the future of New Orleans.

It's neither. Erosion and sea level changes are not at all the problem here.

The problem is that keeping the lowest point dry causes subsurface water to be removed from the area. Also, that water doesn't get replenished. Things tend to shrink when they dry out, and the land under New Orleans is no exception. It's becoming like a shriveled up raisin or sponge.

The more you pump the place dry, the more the place sinks lower.

It's not just a few houses built by irresponsible people.

Nola has the highest port tonnage in the country. The impact on GDP is estimated in the hundreds of billions. There's also billions and billions of dollars of infrastructure here. Most goods that pass through to the midwest and many through the rest of the country come through here.

Without Nola, hundreds of billions of dollars of the economy will go away. Gas prices set a record after Katrina.

14 billion is a bargain to keep this city going.

Sea level has been rising at three millimeters a year as long as detailed measurements have been made. There has been no acceleration in that rate. We are, after all, still coming out of an ice age, and the oceans are still expanding due to accumulated heat.

Locally apparent changes are primarily due to land subsidence due to sediment deposits or rebound after the ice melted.

As I understand it, the Netherlands pays for this maintenance themselves, and not from EU funding? If it were relying on EU funds then I'd expect some kind of European benefit analysis would be required.

I do that, and I agree: I wish people would spend as much time complaining about other people as they do helping them. Yet, 40% of my paycheck is still taken against my will anyway.

I would rather we spent tax dollars on fixable problems with much more social good per dollar. I'm tired of subsidizing flood insurance for idiots that keep building in areas that flood every 10 years. Subsidizing someone to have a nice home on a Miami beech is not "actual good". L

No kind deed goes unpunished, and it's starting to really leave a bitter taste in some people's mouths. The cynicism is real and deserved.

I agree with you re the cynicism.

I would say in these cases though that he levees are the problem. You have silted up channels because the river needs to flood, and the excessive levee system makes that problem more pronounced and contributes to the shrinking of the delta.

That said, New Orleans shouldn’t die. But we’re making the problem worse for most stakeholders in other places.

* > Proceeding to read the article, over a decade the Army Corps of Engineers raised hundreds of miles of levees. If this were a thread about how the US can't complete big projects any more, that alone would be a ray of sunshine.

Unfortunately even that sunshine requires applying sunscreen as it reminds of their calculations that don’t favor helping the most people.

Still, even if the [Army Corp of Engineers] approach is designed to avoid picking winners and losers, it ends up doing so anyway, favoring wealthier neighborhoods. "It's also going to be [choosing] more valuable businesses," Kling says. "More valuable real estate."

https://www.npr.org/2019/03/05/688786177/how-federal-disaste...

Feigned moral indignation over 'cynicism' won't change the fact that real money was really wasted.

> Instead of worrying about the state of the world, spend an hour of your social media/fuck around time a day/week/month doing something for someone else. It'll do some actual good.

Also, speak for yourself. You don't know what people spend their time doing outside of writing comments on HN.

Wait America deserves a pat on the back for providing basic infrastructure? What standards do we hold the US to, Bangladesh or the Netherlands?

>Instead of worrying about the state of the world, spend an hour of your social media/fuck around time a day/week/month doing something for someone else. It'll do some actual good.

Unfortunately, the current zeitgeist is one in which if you say the wrong thing, are misinterpreted, "mansplain" or simply disagree with the wrong people you're going to get railroaded, brigaded, reported to authorities, fired or blacklisted.

In a world like that, where everyone is an opponent, who wants to "help their neighbour"?

Well I came to comment no this:

>> “I think this work is necessary. We have to protect the population of New Orleans,”

Not that I like either option, but I'd rather my tax dollars be spent on relocating these people than fighting an eternal war against the inevitable march of nature. Can I do anything personally about it? Not really. Certainly far less than any individual who lives there. But if my taxes are going to be used to help, then please help in a way that is more effective than doing the same stupid thing (building below sea level) that they've been doing for a hundred years.

Nola has the highest port tonnage in the country. The impact on GDP is estimated in the hundreds of billions. There's also billions and billions of dollars of infrastructure here. Most goods that pass through to the midwest and rest of the country come through here.

Without Nola, hundreds of billions of dollars of the economy will go away. Gas prices set a record after Katrina.

14 billion is a bargain to keep this city going.

They're not keeping it around to be nice.

Hundreds of millions of dollars is barely a blip on the federal government's budget.

Federal dollars subsidize all kinds of local and regional infrastructure.

>how are we going to deal with this at any kind of scale?

Get the Army Corps of Engineers to hire the Dutch.

https://en.wikipedia.org/wiki/Water_board_(Netherlands)

How much do the Feds collect in taxes from the city each year? How much more will they collect in the future because the city floods less? A few hundred million dollars to protect a major city sounds like an incredible bargain with a great ROI.

New Orleans isn't the most unsustainable place around. The intractable swampy surroundings have prevented it from becoming as suburbanized as most American cities; if you look at it from a satellite, there is a sharp boundary between the city and the swamp. The situation is much worse in, say, Miami. Many other coastal cities will also need levees and have uglier boundaries.

Off the coast of Louisiana is the Mad Dog spar oil platform, installed in 2005, which at maximum production is pumping 100,000 barrels of oil a day. Louisiana receives no tax revenue from it.

New Orleans only has about 300,000 people. There's high ground a few miles north. Relocation, not levees.

Florida is worse off. Florida doesn't have much high ground.

Nola has the highest port tonnage in the country. The impact on GDP is estimated in the hundreds of billions. There's also billions and billions of dollars of infrastructure here. Most goods that pass through to the midwest and many through the rest of the country come through here.

Without Nola, hundreds of billions of dollars of the economy will go away. Gas prices set a record after Katrina.

14 billion is a bargain to keep this city going.

The US Army Corps of Engineers is generally and historically responsible for waterway dredging and flood control. It's one of their core (peace-time) responsibilities. These are typically large projects that benefit the public good yet are rather complex and lack sufficient financial incentives for privatization. The wikipedia article [1] gives a general idea of how and when this came to be. (Canals.)

1: https://en.m.wikipedia.org/wiki/United_States_Army_Corps_of_...

It is a bit odd, but the Army Corps of Engineers has historically always been responsible for a lot of maintenance of the country's rivers and waterways, dams, parts of the Great Lakes, etc. including flood control.

As an American I know. These levees were built KNOWING that they sink at a mathematical formulate rate. This is FAKE NEWS. The 14 billion dollar cost is a cost rate over a decade or more, lets say 1 billion at 14 years long. This billion a year is the cost to keep adding on to the existing well made and constructed infrastructure.

The Army Corp of Engineers can be viewed as the federal government's civil engineering service. See https://en.wikipedia.org/wiki/United_States_Army_Corps_of_En... for a good description.

It's complicated. The Army Corps of Engineers has had a civilian mandate to support flood control prevention since 1917 [1]. Beyond that, they are also involved in large public works projects such as the building of roads and bridges, and Superfund clean-up sites. On top of this, they regularly receive large pork barrel grants from Congress that can siphon money into a senator's state or a congressperson's district. They do have a large contracting arm and are actually pretty well-regarded for their comprehensive procurement and management process for these large public works projects.

So it's scale, politics, and history/momentum at this point.

[1] https://en.wikipedia.org/wiki/U.S._Army_Corps_of_Engineers_c...

> As a non-American, can someone explain to me why the army was responsible for this work?

Because...path dependency. The Army Corps of Engineers has long been responsible, largely, as I understand it, from mission following capacity rather than vice versa.

> When does the normal tender/contractor process not occur?

It can, but that process requires a government agency over the top, and the ACE is the responsible agency. They contract out work.

They have a concept of “waters of the United States” where if it’s a navigable water it is federally managed and historically army cane first so their Corp of engineers are the ones who carry out the operations

With 14 billion dollars you could move a lot of that culture and history to somewhere with less need for swimming lessons.

Is it a new problem? The dustbowl hit, and some people were completely unwilling to move, even though their way of life was unsustainable.

Change is inherently hard to deal with. I think one of the big roles of government, and perhaps culture, is to temper the peaks and valleys. Some of us are going to face hard hard choices. Some of those choices are very rapid, like an earthquake. Some of those choices are very slow, like rising sea levels.

We pretty much know that there will be earthquakes and rising sea levels. How do we influence people to minimize that impact today?

I'm a fan of big cash payouts for flood insurance in exchange for losing the land, ever increasing taxes on the sale of costal properties and converting coastline to national park.

When folks homes are inevitably destroyed, make sure they have plenty of money to move. Make it harder and harder to sell property on the risky coasts, and finally when enough homes have been destroyed (50%? 95%? doesn't really matter the higher the fraction, the more painful the change will be), take the land and turn it into parks for everyone to use.

I'm not exactly opposed to the very wealthy hanging on to a cabin or a mansion, but there needs to be a clear line that they are living on public land. People can camp in their yard.

Maybe it's a stupid idea. We do have an opportunity to unwind the massive, massive risk incurred by allowing, even encouraging, people to live in places where they will fail miserably, eventually.

Right now, the risks are low. So the stakes should be low. I have no problems with my tax dollars giving a small bonus for them to move away, and turn that land into national park. In 50 years when they are well and truly fucked - who cares? Maybe stop issuing flood insurance in 40 years. Plenty of time to figure out a plan.

But where they are living is increasingly risky. Slowly, gradually make it clear that we as a culture and government aren't going to subsidize that. It's ok if they are super-rich, and can afford to rebuild every few years. but the land will be nationalized eventually. And no one is going to subsidize rebuilding efforts in the very long run.

A thousand times this. Sandy Rosenthal and levees.org have kept the drumbeat going.

There is proper technology for places below sea level. We should learn from the Netherlands - they're masters of reclaiming land from the ocean.

And like Miami, NYC etc. in the coming years.

Providing relocation assistance to incentivize people to go elsewhere piecemeal, rather than trying to move them all to one place together?

Whenever property is completely destroyed in a floodplain they could offer say a 5% bonus to their insurance payment from the government if they give up rights to that property and no longer use it for housing or business, alternatively they could rebuilt the structure on pylons, propping it up above the flood levels. And if they decide to rebuild despite that offer, you could remove all eligibility from the subsidized cost of government-backed flood insurance, and instead let them take on the full cost of private insurance flood coverage rates.

>"moving a whole city" feels even harder

Could do it for Chicago around the 1850's; 'Raising of Chicago' - https://en.wikipedia.org/wiki/Raising_of_Chicago

1) They certainly don’t blame lack of silt 2) There’s a new power plant going up at Michoud (albeit a bad idea for other reasons)

Yes, much of it is below sea level and stupidly expensive to quite literally keep afloat. It's quite the expense, and it's probably best to move. It's not the job of the feds to take money from one state to cover the expenses of another.

In a AP neighborhood Facebook group old timers say they’ve seen seepage since the 70s and can’t report any significant raising

Stealing a line from others, but: That's the difference between the US and Europe. In Europe, 100 miles is a long distance. In the US, 100 years is a long time.

I think new orleans will in part survive as a bit of a disneyland city. I can't imagine that there aren't some parts that are worth saving.

This is the Feds we’re talking about here, not our sainted Orleans Parish Levee board