There are many reasons why true dedicated high-speed rail is superior to slower, mixed-traffic rail. True HSR is oil-free because it is powered by electricity. True HSR also offers shorter trip times, which translates into higher ridership, reduces congestion across all other modes and delivers these benefits with higher profits and lower operating costs. Given the energy-constrained future we face, a hierarchy of rail must be built quickly to become the main form of transportation in America, with true HSR as the backbone of the national system. We can’t afford not to build true HSR! Oil prices will continue to
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.