Part Two: The New Orleans Experience With Extreme Storm Design Standards Is Instructive
Under-design – based on lax regulatory standards & cost considerations – can kill
Who will tell the people about this looming disastrous DEP decision?
In completing its draft report earlier this year, the Corps turned down a request by state and local officials to consider increasing protection to at least a 200-year level, or to a 500-year level of protection. It wasn’t justified, officials said.
“While the 200-year level of risk reduction alternative was competitive, its net [economic] benefits were lower than that of the 100-year level of risk reduction,” said Ricky Boyett, a Corps spokesperson. “Because of the lower net benefits, the 200-year level of risk reduction was not selected as the recommended plan.”
Such a cost-benefit analysis is part of a federal standard that compares reductions in property damages, emergency costs and the avoidance of economic losses from flooding against construction costs. (NoLA.com)
In yesterday’s post, in order to illustrate and draw a parallel between what is happening in NJ and what already occurred in New Orleans, I excerpted a key 2019 finding by the US Army Corps of Engineers from the Federal Register.
The astonishing USACOE finding was explained by Scientific American:
After a $14-Billion Upgrade, New Orleans’ Levees Are Sinking
Sea-level rise and ground subsidence will render the flood barriers inadequate in just four years
The $14 billion network of levees and floodwalls that was built to protect greater New Orleans after Hurricane Katrina was a seemingly invincible bulwark against flooding.
But now, 11 months after the Army Corps of Engineers completed one of the largest public works projects in world history, the agency says the system will stop providing adequate protection in as little as four years because of rising sea levels and shrinking levees. […]
The agency’s projection that the system will “no longer provide [required] risk reduction as early as 2023” illustrates the rapidly changing conditions being experienced both globally as sea levels rise faster than expected and locally as erosion wipes out protective barrier islands and marshlands in southeastern Louisiana.
Let that sink in: a $14 billion levee upgrade – a project that was designed after an under-designed levee system failed and killed over 1,800 people – repeated the original under-design and as a result, was no longer adequately protective and effectively obsolete after just four years.
Deja vu: The levees that failed in New Orleans during hurricane Katrina were under-designed. They were designed to survive a Category 3 storm.
Katrina was a Category 4 storm and exceeded the levee design standards. The Army Corps initially admitted this: (Washington Post)
Johnston said the Corps intends to launch an investigation to make sure it is correct about that scenario. But he emphasized that Katrina was a Category 4 hurricane when it smashed into the Gulf Coast, whereas Congress authorized the Corps to protect New Orleans against a storm only up to Category 3. “The event exceeded the design,” Johnston said.
Several detailed forensic investigations later found the levee failure was caused by both under-design and poor construction.
The Corps’ Federal Register notice I cited was issued to announce an environmental impact statement on evaluating options on how to fix the problem caused by the post-Katrina under-design and upgrade the levees.
Here is the debate from post Katrina New Orleans that the Murphy DEP is trying to evade and the NJ press corps is not reporting – and it’s all about money versus death and destruction: (NoLa.com)
In completing its draft report earlier this year, the Corps turned down a request by state and local officials to consider increasing protection to at least a 200-year level, or to a 500-year level of protection. It wasn’t justified, officials said.
“While the 200-year level of risk reduction alternative was competitive, its net benefits were lower than that of the 100-year level of risk reduction,” said Ricky Boyett, a Corps spokesperson. “Because of the lower net benefits, the 200-year level of risk reduction was not selected as the recommended plan.”
Are any local or NJ State officials demanding that NJ DEP adopt a more protective 200 – 500 year design storm standard in DEP regulations? Why don’t we even know about this?
How could this happen? How could US Army Corps of Engineers have failed to consider climate change and subsistence in the design of a $14 billion project? Scientific American explains:
The agency’s projection that the system will “no longer provide [required] risk reduction as early as 2023” illustrates the rapidly changing conditions being experienced both globally as sea levels rise faster than expected and locally as erosion wipes out protective barrier islands and marshlands in southeastern Louisiana.
The technical crux of the failure is not limited to rapidly rising sea levels, and local erosion and land subsidence. It also involves what is known as the statistical design storm: the probability of the amount of rainfall that engineers estimate might occur in an extreme storm – two distinct scientific and engineering tissues that are conflated in the Scientific American story:
Sea-level rise raises questions about whether the protective system—known officially as the Greater New Orleans Hurricane and Storm Damage Risk Reduction System—should be built to a higher standard.
When Congress approved funding after Katrina, it required the system to protect against a so-called 100-year flood, which has a 1% likelihood of occurring in any year.
The USACOE explains:
As the Army Corps studies reinforcing the system, it will model the effect of roughly 150 storms ranging from a small tropical depression to a mammoth 500-year storm that has only a 0.2% chance of occurring each year, said Roe, the agency spokesman. A first draft of a report is scheduled to be done by December, after which the Army Corps will accept public comments.
Bingo! The Corps will consider:
a mammoth 500-year storm that has only a 0.2% chance of occurring each year
But Corps engineers rejected local and State requests and retained the 100 year design storm
Following that study, the US ACOE rejected local officials to upgrade the project based on the 500 year storm: (Nola.com)
In completing its draft report earlier this year, the Corps turned down a request by state and local officials to consider increasing protection to at least a 200-year level, or to a 500-year level of protection. It wasn’t justified, officials said.
“While the 200-year level of risk reduction alternative was competitive, its net benefits were lower than that of the 100-year level of risk reduction,” said Ricky Boyett, a Corps spokesperson. “Because of the lower net benefits, the 200-year level of risk reduction was not selected as the recommended plan.”
Pure economics drove the decision. Sort of an engineering death panel: the value of life is traded off with property damage and construction costs.
The Murphy DEP and NJ press corps are not even engaging this debate. The NJ press corps is not reporting on this issue as far as I know.
As I wrote yesterday, it is now clear that DEP will retain the current 100 year design storm.
There is no NJ State law requirement for DEP to justify that decision publicly and consider alternatives like the Army Corps was required to do under NEPA.
As NJ recently learned with flooding caused by tropical storms, the current 100 design standard is totally inadequate, and the future repeat flooding due to increased rainfall and extreme storm events driven by climate change will only make flooding even worse.
Who will tell the people about this looming disastrous DEP decision?
It was enough to blow the Party to atoms, if in some way it could have been published to the world and its significance made known. ~~~ 1984, Orwell