Oh. My. God.
This one is aimed at the engineers in the audience, but everyone has to read it.
We know the following information about the welded pipe that runs from the drive units to the pump units, conveying the high pressure hydraulic oil to spin the pump impellers:
Max working pressure = 3000 psi (actually can go higher, see Ms. Garzinos's memo)
Diameter of high pressure line = 3" (see the Floodgates Operating Manual)
Thickness of high pressure line = Schedule 80 (nominally 0.3") (See the original specs, or the job sites. "Schedule 80" is written all over the pipes, which are plainly visible from the levees at Orleans Avenue. I have pictures, which I will post later)
Material of high pressure line = A106, probably grade B (See the original specs), with Maximum Allowable Stress in Tension of 15,000 psi [corrected to 20,000 psi here]
Pipe supplier = MWI (See the original specs)
Engineers in the audience will know to run the numbers through equation (4) in section 104.1 of ASME B31.1 [corrected here]. This is an equation that has been around for decades and is well known to every engineer who has ever specified pipe.
When you run that calculation with just the standard numbers (assuming a standard 12.5% wall deviation, joint efficiency = 1, y = 0.4), you find something absolutely horrifying.
The pipes are too thin to take the normal operating pressures! They're too thin by a lot. When you run the numbers, you find that the maximum burst pressure for 3" Schedule 80 A106B pipe is only 2393 psi [corrected here]. Even if the material is actually A106, Grade C, that still only gets you to 2791 psi. Even when you knock the wall allowance out completely, you still don't get there. When I did this calculation, I actually felt physically sick when I got the result. I've redone it a few times, hoping the numbers were different. They're not. And keep in mind that the pressure can exceed 3000 psi during operations, as also shown in Ms. Garzino's memo.
There are two of these lines on every pump/drive unit pair, each of them about 250 feet long. There is over 17,000 feet of this pipe installed at all three floodgate sites. All of it is unfit for the service it will see. All of it is prone to bursting under normal service [corrected here]. How this could have slipped through so many layers of review is unknown, but I can tell you that if there was a "Fitness for Service" declaration signed, it must be either fraudulent or signed under duress. I bet that the welders working these jobs probably asked for some kind of release from liability, so they wouldn't be blamed when the pipes burst. This is the worst kind of engineering mistake. This is "crash-into-Mars-because-we-didn't-convert-the-units-correctly" stuff.
This is equivalent to driving the sheet piles too shallow on the levees. It is a fundamental flaw in the system that has not been addressed by anyone, and has most likely been covered up to have gone this long. And it could have been remedied so simply: the Corps should have specified Schedule 160 pipe instead of Schedule 80 (by the way, there are questions to be answered as to why a thickness for the pipe was specified, but no diameter. That's very unusual. It's almost like the Corps knew in advance what they were going to get before they issued the specification...).
For reference, I suggest you take a look at this company's website:
This page on their site is particularly instructive.
I have no association with them, other than they happened to have all the information that makes my point - conveniently organized and well written.
This is so incredibly shocking it bends the brain. It appears that the Corps and/or MWI didn't do the simplest of calculations involved in sizing a pipe. Any newly minted engineer who does anything with piping becomes familiar with this equation within five minutes of being handed a job. By the way, that calculation is also called for in the Corps' own engineering manual dealing with piping, EM-1110-1-4008, "Engineering and Design - Liquid Process Piping." It shows up on page 5 [correction: page 16] of chapter 3 (note that the Corps wrote the manual on WordPerfect, so the characters for plus, minus, and equals won't show up properly in Adobe Reader) [correction:
Put simply, all of the pumping systems, as designed, procured, and built, have a strong likelihood of failure when placed under normal operating conditions.
[Corrections to this post are available here]