I had a simple (or not so simple) planning problem I liked to pose to students. You’re planning for a currently undeveloped area on the edge of a large city. The area is expected to see significant urban development over the next few decades. The extent of the development is such that you can anticipate a demand for a major retail center to serve the area. This could be a traditional mall, as in the past, or a new life-style center, or some other type of major retail development. The problem is to select the location for this development.
Now for the details. The area is the flat, featureless plain of location theory, so nothing in the topography would favor any location. The area is served by two major transportation arteries, which could be major arterials, freeways, or rail transport. One extends out from the city through the area that will see future development (say north and south). The other transport artery runs perpendicular to the first through the middle of the area where growth is expected to occur (east and west).
So now, where to locate the retail land use? The immediate, obvious answer is at the intersections of the two transportation arteries (with some of the students rolling their eyes wondering why I had even bothered posing such a trivially obvious problem). Correct!
Except not necessarily complete. The intersection of the two transportation arteries creates four corners or quadrants. In which one should the shopping center be located? Now we’re raising a whole host of new questions: In making a plan, how general or specific can or should one be with respect to specifying such a location? What about when you move to regulating development with a zoning ordinance? Do you choose a corner? What if the owner of land on one of the other corners comes in and says that they want to develop a shopping center? Or do you just allow the shopping center development for whomever asks first?
Each time, the discussion would veer in different directions. But it always provoked thinking about the complexities, uncertainties, and limitations in planning.