If one looks at a more expanded view, the lands provide connectivity for wildlife and other of nature's elements along the western boarder of the City. As one that works in this business daily, I look at these as opportunities to do something a little different. To make allowances for those less recognized values that we seem increasingly able to cast aside.
There is already considerable experience with the integration of these types of environmental design elements into modern transportation systems.
To reduce the risk of collisions and increase the permeability of the highway barrier for wildlife, highway design modifications have traditionally been used, such as underpasses, overpasses, elevated spans, and fences. Data to evaluate crossing structures are available from Florida and other areas (Langton 1989, Yates et. al. 1995, Foster and Humphrey 1995, Land and Lotz 1996, Evink et. al. 1996 and 1999, Boarman and Sazake 1996, Roof and Wooding 1996, Forman and Hersperger 1996, Jackson 1996 and 1999, Simonyi et. al. 1999, MacDonald and Smith 1999, Veenbaas and Brandjes 1999, Jones 2000) and more regionally relevant studies in Banff National Park, Alberta (Clevenger 1998, Clevenger and Waltho 1999 and 2000, Gibeau and Heuer 1996, Leeson 1996, Paquet and Callaghan 1996, Paquet et. al. 1996), which demonstrate that underpasses and extended bridge spans are effective means to increase permeability for some species of wildlife.This text is taken from a 2001 presentation at ICOET - Bi-Annual International Conference of Ecology and Transportation, next to be held 2015 in North Carolina. Elevated spans in the Calgary SW project could make a significant difference in the capacity of the natural world to remain and thrive. Alberta also recognizes this and makes efforts elsewhere to seek alternatives to traditional engineering. A useful resource in the examination of those alternatives includes the US Handbook Wildlife Crossings Structures and the Forest Service Terrestrial Wildlife Crossing Structures.
I would like to think that consideration of these other values is increasingly used in making these sorts of major decisions with permanent but necessary infrastructure.