So what is Re-Urbanization
Re-urbanization is movement of people back into an area that has been previously abandoned. Re-urbanization is usually a government's initiative to counter the problem of inner city decline,pollution, overpopulation, inadequate housing, etc. arise.
Re-Urbanization is actually a really simple process and it doesn't have to be very costly, because many places like Kitchener-Waterloo region have many abandoned factory now this doesn't sound glamorous but it actually can be! (check out this article
http://www.globalsiteplans.com/environmental-design/architecture-environmen... )
These places can be made more Eco-friendly to help reduce energy use and create less waste this mean lower co2 emission and that means less weather fluctuation which helps improve crop yield of crops.
Re-Urbanization doesn't just have to be re doing old and abandon buildings to help increase density, it can also be replacing multiply house for apartments and other buildings the can hold more people or even add to stores or business buildings and adding housing to it.