Engineers just drive you nuts. Whenever you come up with some clever idea, we tell you it's impossible. We then spend the next ten hours complaining about all the things in the world that could have been designed better, but weren't. We thus combine the very worst of optimism and pessimism: "The entire world can be perfected, except for anything you suggest to us, which is totally wrong and actually kind of stupid." If only engineers could be flipped upside down and shaken vigorously, perhaps our bad impulses could be reversed. Perhaps we could become encouraging brainstormers, instead of nagging naysayers. What WOULD engineering be like in a world where anything was possible?
For starters, we would certainly have an easier time dealing with living below sea level.

Home Sweet Dome
We all remember those horrible Hannah-Barbara cartoons we saw when we were kids: The Jetsons, the Snorks, Jabberjaw, Sealab 2020 and so on. What did they all have in common, besides inept animation, idiotic stories, and creepy talking animals? Futuristic domed cities, that's what. It's odd; for a city that officially unofficially uses its football stadium as a hellish, leaking refuge of last resort, you would think that building a watertight dome would be second nature to us. Maybe not the watertight part.
In any event, all doubt should have been removed by last year's Simpsons movie, which clearly illustrated that 21st century imaginary engineering is up to the task of completely enclosing a city in an impervious glass shell (if you did not see the Simpsons movie, congratulations: you are smarter and $7 richer than I).
But how are we going to implement our own Plan Atlantis?  
1. Collect the raw materials. We all know New Orleans has been under a magnifying glass since Katrina. Normally, the idea of everyone in the world watching everything we do (and listening to everything our mayor says) is somewhat creepy. But—as a positive—it means that a 1.3-mile glass disc is currently hovering directly overhead (Fig. 1).
I can hear all you real-world engineers out there flipping furiously through your dusty textbooks and complaining: "A 1.3 mile glass disc isn't big enough to cover the entire New Orleans area!"  True.  We'll need to expand it.
2. We'll take advantage of the well-established fact that the leaders of New Orleans' neighborhood associations can blow anything out of proportion. All we need to do is insinuate, in a well-timed call to WWL, that the glass dome is secretly plotting to limit wind-and-hail insurance coverage in Lakeview, build a bar on Maple Street, and atom-bomb the Ninth Ward. The neighborhood associations will take over and inflate the dome to nearly 10 times its previous size.
3. Next, we'll have to seal off the dome from the raging waters of the Gulf. Luckily, in New Orleans we manufacture the stickiest, most tenacious substance known to the human race: the filthy, horrifying patina that coats Bourbon Street on Sunday morning.  This goo is manufactured free of charge by tourists, and only tourists are injured in its production.  Oddly, they effectively pay us for this service.  Currently, this toxic adhesive is scoured away with a Kryptonite-and-eucalyptus wash by the wizards at SDT Waste & Debris. Although the exact disposal process is a carefully guarded trade secret, I suspect they condense the residue in giant tanks and launch it into the Sun (Fig. 2). We simply need to convince Sidney Torres to use the ooze to anchor our protective dome. Perhaps we could bribe him with hair products.
4. The final step will require us to devise a means of safely getting people in and out of the structure. My original idea was to simply not invite everyone who needs to come into the city to one of my crawfish boils. They'll then inevitably find a way to show up unannounced, with two friends and no beer. Unfortunately, this plan would be far too costly. Instead, we'll have to divert the I-10 through a portal in the glass. Luckily, construction work on the I-10 never takes long (Fig. 3).