DHV Bertrand van Ee, to be chairman of the merged group. Related Links: DHV Prepares 100-Year Flood Plan for Vietnam's Mekong Delta Netherlands-based DHV n.l., Amersfoort, and Royal Haskoning group have agreed to merge, forming one of the world’s largest independent design firms, with combined annual sales of $940 million.The new group’s main activities will be in the maritime, water and delta sectors, in addition to aviation and transportation.To be named Royal Haskoning DHV, the firm will be based in Amersfoort and will chaired by Bertrand van Ee, who holds the same position in DHV. Erik Oostwegel, Royal Haskoning’s chairman,
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.