The beautiful Zakim bridge has become a Boston landmark.

To the casual observer, civil infrastructure may seem pretty straightforward and even mundane. A road is just a ribbon of asphalt. A bridge is an elevated road spanning an obstacle. A railroad is a line of track and some stations. Even the dictionary spares little effort on infrastructure, dismissing it as "the basic facilities required for the functioning of a community."

Look closer, however, and big infrastructure projects reveal themselves as among the most complex and challenging of all human undertakings. Inextricably linked to the communities they serve, they often must be built amid the snarl of traffic and the hive of commerce—without disrupting the flow of daily life. Moreover, large infrastructure projects can take years to complete, forcing builders to cope not only with changing conditions on the ground, but also with shifting political and economic forces.

Given the enormous challenges, as well as the considerable cost, it would make sense for big infrastructure projects to forego aesthetic considerations and focus on utilitarian designs. Yet, as Bechtel has shown time and gain, infrastructure can be beautiful.