Sustainability and Bridges

How should bridges be considered with regard to sustainability? Should it be by maximizing the use of recycled materials and minimizing CO₂ emissions and the use of water? Alternatively, should it be by taking its impacts on local communities during their planning and execution into account? Or, might it be by designing bridges to minimize the need for maintenance and repair during their intended service lives? None of these approaches is necessarily right or wrong, but none on its own suffi ciently addresses the breadth and complexity of the challenge posed by sustainability and sustainable thinking to all those involved with bridges—as owners, designers, constructors, maintainers, and users.