Lake and high ground

This idea will be expensive, but in the end, I think such a scheme would be worth it.

First, get some land, I'm thinking 2 adjacent square mile plots. dig out 30 feet of dirt+rocks from one plot and spread it evenly on the other. If some minable materials are recovered, mine them.

Then, do whatever it takes to turn the pit into a lake. If it needs some strategically place concrete to keep the water from draining away, do it.

Also, do what it takes to keep the dirt in one place. I imagine you might need trees, and topsoil, and a lot of patience.

After some 20 years, though, you'd have some prime real estate-- all the houses will be 30 feet above the water, and yet have a great view of it.

Getting water for the lake might prove expensive, the maximum evaporation rate for a square mile of water is 4.4 million gallons. But, this will not be so bad if you populate the town build on the high ground. since the average american household uses 100 over gallons a day, the processed wastewater of 50,000 homes will prove plenty to start filling the lake.

Once it's filled, a new wastewater management regime could maintain the lake at the desired water level.

Such a project would involve tranporting about 840 million cubic feet of dirt one mile, but that isn't that much. It's 32 million cubic yards.

http://www.heavyequipmentnews.com/hen/article.asp?article_id=61775

Earthmoving operations cost around $3 per cubic yard, so it'd only cost 90 million dollars.

Considering the fact that we plan to build enough living space up top for 50,000 homes(which will probably be multistoried apartments of various size), that's only an additional cost of $1800 per home. Negligible.

You'd still need an insane billionaire and tons of permits to get this project started, but it's very possible.