Single-family housing fared far worse than expected this year but could rebound in the coming years, according to the National Association of Home Builders. During NAHB’s Construction Forecast Conference on Oct. 27, chief economist David Crowe estimated that 2010 will close with an 8% increase in single-family home construction starts to 479,000 units. That is a major adjustment from NAHB’s May forecast, which predicted a 25% increase this year. Multifamily housing has fared better than expected: Although its May analysis called for an 18% drop in starts, NAHB now forecasts a 12% rise for the year to 125,000 units. Crowe
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.