There are parts of the world where entire villages have been built in shallow waters. One example is the Sulu Sea, a huge shallow area in the southwest part of the Phillipines. Around Sitangkai Island, a community larger than the island is built on stilts. Amusingly, the island is used for cemeteries, so only the dead there live on land. The aquatic portion calls itself "Little Venice of the South", although the name is belied by its ramshackle, makeshift nature. Ron Gluckman's article Real-Life Waterworld is an interesting discussion of the area [Gluckman1996]