Can elevated pedestrian walkways be sustainable?

In most North American cities, taking pedestrians away from the street level potentially kills the street life. Raised walkways perform as lines connecting otherwise disconnected urban islands together, but fail quickly where pedestrian density is not high enough to sustain both levels. The networked connectivity acts not only as a public space linking together the built environment, but also distances pedestrians from vehicular pollution while redistributing the density of the ground layer. This paper looks specifically at how Hong Kong is able to sustain such a unique phenomenon facilitating permeability accentuated through a network of elevated walkways when most North American cities fail to function successfully for various reasons. It concludes by demonstrating how elevated walkways have been utilized for years; yet still project a visionary idea for future sustainable urban design.