The California Air Resources Board admitted recently that today’s off-road diesel equipment will easily meet the state’s emission goals for many years to come. However, the board is not giving up on pushing forward its regulatory agenda of monitoring and controlling the emissions of the industry’s construction fleets. Photo: Tudor Van Hampton For ENR What may console the construction industry, however, is an expected series of delays to CARB’s nitrogen oxide (NOx) and particulate matter reductions, which were scheduled to kick in this year for large fleets (over 5,000 hp), in 2013 for medium fleets (2,501 to 5,000 hp) and
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.