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The story is set in a submerged city or community complex, anchored to the sea floor by tethers I believe. The story is centered around the POV of a kid, probably teenage. He was portrayed maybe 14-17 years old.

The first event I remember is one of these anchored homes caving in and collapsing to the sea floor. The main character (MC) witnessed the event and rushed in to save and rescue what/whoever he could.

The second event I remember is the MC and some female friend of his exploring an abandoned wreck of some structure and, in the midst of it, hearing the sound of a distant whale outside the structure propagating and reverberating through the metal structure.

The third event I remember is the ending, however, I'm presently on the mobile app of SE and don't see a button for spoilers (despite the ample space available for one) and I don't remember the special string of characters needed to create a spoiler, so I'll save typing it for later. Suffice it to say that the story ended happily, with plenty of dolphins.

There are other aspects of the story I remember as well.

I believe the MC lived on an aquatic farm homestead sort of ordeal, growing some kind of aquatic plants for the community. Their nearest neighbors did this as well. They all lived some distance from a central community with hundreds or thousands of citizens involved.

Most of these civilians were in denial of "mutants" emerging from their specialized community. I believe they shared stories about witnessing the feats of these mutants like we landgoers share ghost stories. In the end the MC and a number of other children end up being mutants themselves, adapted in some minute ways for living within water.

Some of these hypothetical mutants are blamed for a string of incidents and disasters in the communities and city, such as that one homestead collapsing and sinking (also, as it comes to me, I believe they managed to patch the sunken house up and inflate it again). I believe that during that event the MC chases down a culprit and witnesses something or someone mutant-like, driving his own suspicions and the plot further.

To live and work in the water, I believe the citizens inhaled in a kind of oxygen-rich liquid which allowed them some time to function in the depths without special breathing apparatuses.

I don't remember much about the regional setting, like where or when this place was situated, but I think there was a coastline city nearby.

The story seemed geared toward young adults and was likely written recently. I'd be surprised if it was written any later than 1990, and my impressions tell me sometime between 2000 and 2010. It was written in English and the copy I borrowed was printed on a paperback.

marked as duplicate by DavidW, amflare, TheLethalCarrot, Edlothiad, FuzzyBoots story-identification Apr 3 at 20:24

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  • 2
    Intentionally hiding parts that you remember is a bad idea. The spoilers you're avoiding talking about could easily be the trigger for someone's memory. – Valorum Apr 3 at 18:14
  • This question would be improved by going through the checklists here; How to ask a good story-ID question? – Valorum Apr 3 at 18:15
  • possibly the same as scifi.stackexchange.com/questions/138230/… – Otis Apr 3 at 18:46
  • @Otis I agree. Funny that, after searching through the results for "underwater city" and "underwater sci fi" and so on, I didn't stumble across that one. – BMF Apr 3 at 19:04
  • @BMF, That's why your question is valuable, too. Welcome to the stack! – Otis Apr 3 at 23:19

Sounds like Monica Hughes Crisis on Conshelf Ten.

The young hero is Kepler Masterman, a visitor from the Moon Colony. He and his new friend find themselves caught up in a conflict between the citizens and the "gillers" (mutants) and narrowly succeed in heading off a full-blown revolt.

Crisis on Conshelf Ten cover

(The Review on Kirkus expands on some of these elements.)

  • Yes, this must be it! Thank you! – BMF Apr 3 at 19:02
  • I'm surprised at just how wrong some of my estimations of the story were. The similarities are pretty certain, but a lot of what I thought was in the story or what impressed me about the story certainly wasn't the case. Interesting – BMF Apr 3 at 19:06
  • @BMF That happens more than you might expect; virtually every story-id question I've asked has had at least 1 element that's completely wrong. – DavidW Apr 3 at 19:45
  • I'm the same. A few years back I rediscovered a Twilight Zone episode which I las saw when I was 14, and found at least two points quite different from what I "remembered". – Mike Stone Apr 4 at 9:20

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