Why Egypt Is Building a New Capital City

This video has failed to discuss some very crucial elements of any city infrastructure. How is mas transit planned? What kind of metro rail lines are planned and how they connect all parts of city (if it does). From where does all the water required for this future megapolis will come from? How sustainable is this whole design?

And the most important point: How will this trillion dollar project be funded? Is the Egypt economy big enough to fund such an ambitious project?