I hear you.
And yet… re infrastructure… there are cases where that hasn’t stopped people from living in floating in uh grouped-together-units. Appropriate technology can and does give rise to novel, effective approaches using available materials, minimal to zero budget, and hella ingenuity. These folks never fail to amaze me:
Granted, the OP was talking about ocean-based floating cities and clearly these are villages that are floating in marshes which don’t get gigantic rogue waves etc. Btw the Marsh Arabs have the opposite problem: the water in their marshes is being diverted and mismanaged.
I digress.
Well, there’s the U.S. military.
Talk about “significant amount of money…”
A U.S. Navy aircraft carrier is a kind of floating city. It is not a strictly closed-loop, “sustainable in the classical sense of the word” floating city. The largest classes of these carriers will hold 3000-5000+ service members [people] who all have jobs. They just don’t raise their own food. No idea how they are handling wastewater and garbage either. These ships are usually powered by nuclear reactors, so I suppose their energy supply is sorted.
At least we can safely assume that a “Perfect Storm” scenario has been gamed and considered at length because these ships are insanely expensive.
If you’re in a place with plentiful sun and oodles of salt water, direct solar desalination (via evaporation) is ridiculously easy. Little solar stills are standard equipment on oceanic life rafts, for example.
From life raft solar to gigantic emplacement, it also happens to smoothly scale for any use. All you need is the sun and water…
Heck, you can make a solar still with a black trash bag, salt water, the sun, and a bucket =D!
Infinite concern ‘I am having second thoughts about building my home along waystations in the sub-Pakistan Hyperloop,’ or infinite concern ‘Butte, Montana didn’t used to have hurricanes, but the mattmoss seem to love them?’ I mean, you spend one hurricane watching 4" plywood breathing heavily and another watching acceptable architectural glass weathering, book glass delivery once, and it’s pretty mellow.
Get told your caissons are likely to flip, ask ‘did we just flip?’ that’s another mellow.
