perhaps it would be useful where there is a space constraint, downtown areas where shops are not on the main floor, and where it snows ( no snow in phoenix... except twice that I have ever seen, and it melted as it hit the ground) in rural areas and suburbs the density is too low to justify that construction. Considering downtown Phoenix, there could be some useful places where a raised walkway would benefit the people and allow for more traffic after dissolving the sidewalk, but considering crime: if police have to travel that much farther to respond to a pedestrian incident... what happens to the pedestrian?