The first point that should be made is to reinforce the statement that most current Local Governments do not have the scope to achieve what is illustrated here. Regional planning is a necessary prerequisit.
So, after we get rid of State Gov'ts and create Regions instead, it will be possible to create such areas and retrofitting existing urban environments will be facilitated.
The second point that should be emphasised is that urban planning leads to a semi-permanent built environment. If you get it wrong, it is wrong for a very long time. Fortunately there are now computer models that allow urban planners to trial plans before they are built. Dozens of criteria can be applied to any plan; and infinite variations of each criteria can be applied and the results assessed.
Thirdly, there is no need to reinvent the wheel. Eco-friendly urban areas have been built in various places. Freiburg in Germany is just one other example. I haven't checked but am sure a Google search will show the several areas in Germany that have been built this way.
The Draft Constitution of the Foundation for National Renewal calls for regions to be established based on water catchment areas. This is another significant contributing factor to eco-friendly urban, suburban and rural design.
Charles Mollison