Photo: DHV Group Vietnam bridge initiative will allow much larger vessels to travel the Mekong River. Vietnam’s ministry of transport, public works and water management has launched a four-year, $100-million project to improve navigation along 250 km of the Mekong River, a key transportation corridor. Netherlands-based DHV Group has won a contract covering design and management, and construction is due to start in a year. Work on 18 existing and new bridges, as well as a lock, will allow 600-tonne vessels to ply the river, about 20 times bigger than those now in use.
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.