Each year the U.S. places about $100 billion of roadway construction. This level of activity suggests there may be significant sustainability implications in the construction activities that perform this work. One means to quantify some of these impacts is through life cycle assessment (LCA). Areview of 14 roadway construction LCA papers reveals some common ideas about the ecological impacts of roadway construction. Some key observations are: (1) the energy expended during roadway construction is roughly the equivalent to that used by traffic operating on the facility over 1-2 years,(2) total energy use during roadway construction varies but is typically on the order of 3-7 TJ/lane-mile, (3) total CO2 emissions during roadway construction varies but is typically on the order of 3-7 TJ/lane-mile, (4) materials production: 60-80% of energy use, 60-90% of CO2 emissions, (5) construction activities at the jobsite make up less than 5% of energy use and CO2 emissions, (6) transportation associated with construction makes up 10-30% of energy use and about 10% of CO2 emissions.
Abstract