City on a Turtles Back

[Raptori]

It all depends what "5 gallons of water a day" constitutes. I'm guessing it'll be the water used for drinking, cooking, washing, etc - everyday water use. In that case, the reason the numbers this gives you seem extremely low is that this particular section of water use is actually a tiny proportion of the amount a person's daily life consumes.

Take food for example, it takes over 100 gallons to produce 1 pound of corn, about 100 gallons to produce a single potato, and exponentially more to produce meat, such as 4,000 - 18,000 gallons to produce a hamburger. Clothes also use a lot of water, a modern cotton t-shirt taking 2,700 gallons being a common statistic. Industry also consumes a huge amount of water. Generally speaking, water use embedded in property and food seems to outstrip "basic" water use by a factor of several thousand (or actually tens of thousands if you're eating a lot of meat and consuming a lot of processed goods).

I guess that's why it's hard to find out concrete numbers - so much depends on the level and distribution of technology in the society. A less developed society would use a lot less water than one with heavy industry. I'd guess that the population density estimates people generally use would have this kind of limitation included inherently - at medieval technology levels, those densities would make sense based on all limitations, rather than just crop productivity. Also, a heavy dependency on fish as a source of food would help to lower water use. Maybe they could also plant and grow kelp underwater too (might have been mentioned before, but I can't remember).


As to the map, looks like a good start, though it bugs me that the shell isn't centered!

I also think it'd be nice to include the head in the map too, it looked better when it was included.