In the void left by collapsed construction markets around the world, transportation projects are not only a holdout of relatively robust activity but are embraced globally as a vital step on the road to recovery. Firms in the transportation sector are crisscrossing the globe as developing nations race to build new roads, railways and airports, while in America, Europe and the Middle East new technologies and growing populations are pushing projects forward. In the sector currently are some of the largest projects in the world, such as the $10-billion Al Maktoum International Airport being built in Jebel Ali, United Arab
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.