International donors have pledged $5.3 billion for the first stage of a plan to help earthquake-devastated Haiti rebuild. Among pledges made at a March 31 conference was $1.15 billion from the U.S. Haiti says it will need $3.9 billion for the 18-month first phase of the plan. The Jan. 12 magnitude-7 quake caused more than 220,000 deaths and destroyed about $4.3 billion in housing, roads and other infrastructure.
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.