More Roads, More Traffic
The Failure of Road-Building to Alleviate Traffic Congestion in Maryland

Executive Summary

Despite spending millions of dollars to build 7,000 lane mile to its road network from 1985 to 2000, Maryland’s congestion problem continues to get worse. A major reason is generated traffic—the new, longer, or diverted trips that develop once highway capacity in an area is increased. Generated traffic reduces or negates the congestion-fighting benefits of highway expansion. Evidence from university studies of congestion patterns, government statistics on transportation and academic research shows that highway expansion is not an effective way to fight congestion. Maryland should shift its transportation strategy away from costly highway expansion projects and toward alternatives that can provide more transportation choices to residents.