Photo by Tudor Van Hampton for ENR Manufacturers have spent billions of dollars to make diesel engines meet Tier-4 Final. Related Links: Product Snapshot: Caterpillar's CVT Wheel Loaders Tax Law Changes May Hurt Equipment Sales, Boost Rentals in 2014 Will Tier-4 Engine Challenges Bring New Opportunities? As a January deadline to clean up off-road diesel emissions approaches in the U.S., prices are expected to rise in 2014 to pay for the new technology. However, better fuel economy will help offset the up-front cost."We've looked in every nook and cranny, trying to save fuel," said Bill Campbell, product application specialist for
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.