Robert A. Olmsted, the first director of long-term planning for New York City’s Metropolitan Transportation Authority (MTA) and a transportation engineer, builder, historian and industry mentor for more than 60 years, died on Aug. 16 in Manhattan. He was 85. Olmsted early in his career at the Brooklyn Battery Tunnel (left) and at the 2009 Manhattan Bridge centennial. Olmsted—a descendent of Frederick Law Olmsted, the landscape architect who designed New York City’s Central Park—began his own industry career in the late 1940s as a Cornell University engineering graduate on the Brooklyn Battery Tunnel. A protégé of Ole Singstad, the innovative
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.