Related Links: Singapore Building and Construction Authority The U.S. Green Building Council In Singapore's densely built-up urban environment, with limited land and few natural resources, greening buildings is vital to sustainability and one of the most effective ways for a city to reduce its carbon footprint. As recently as the 1990s, countries in tropical and subtropical regions had few existing guidelines. What did exist originated primarily in the U.S. and Europe and didn't necessarily apply to Singapore's very different climate.By the mid 2000s, the Building and Construction Authority began developing our own green-building rating tool designed specifically for tropical conditions:
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.