SEQUEL IS COMING (no bullshit)
https://www.hollywoodreporter.com/tv/tv-news/waterworld-sequel-tv-series-1234990300/
i guess all the current climate change stuff is responsible for this going ahead..
i imagine Costner will feature in that mythical lost figure way - Luke in TFA/TLJ, Deckard in BR2049 (and the main character will probably be the grown up girl from the movie)