MDOT SHA Celebrates 25 Years Since First Roundabout Installed

(June 1, 2018) – From a bird’s-eye point-of-view, they resemble mysterious crop circles made of a mixture of asphalt and concrete. From a driver’s perspective, they save lives, and a lot of them. The Maryland Department of Transportation State Highway Administration (MDOT SHA) is celebrating the 25th anniversary of installing its first roundabout in Lisbon, Howard County.

“As roads get busier and growth continues, roundabouts are increasingly becoming a go-to solution to solve complex highway issues,” said MDOT SHA Administrator Gregory Slater.  “Roundabouts have been proven to improve safety by eliminating vehicle conflicts and, to date, there have been no fatal crashes for vehicles driving within a roundabout.”

In the early 1990s, the MD 144 (Frederick Road)/MD 94 (Woodbine Road) intersection in Lisbon, Howard County, was experiencing many crashes and severe congestion during peak drive times. MDOT SHA traffic engineers evaluated the intersection and had a relatively new traffic calming application in their safety tool box, a traffic circle. Eliminating 90-degree intersection angles and introducing right-turning, continuously moving lanes would cause drivers to slow down and reduce vehicle-to-vehicle conflicts while reducing intersection-related congestion. MDOT SHA installed a temporary roundabout using line striping and rumble strips and evaluated the function of the roundabout.

Relishing the success of the temporary project, MDOT SHA construction crews made the roundabout permanent, opening it to traffic in April 1993. Since its inception, there has been a 77 percent crash reduction and no fatal crashes.

This success in Lisbon gave birth to a solution to an extremely dangerous and equally frustrating situation in the heart of Towson. In 1996, MDOT SHA connected MD 146 (Dulaney Valley Road), MD 45 (York Road), Allegany Avenue and Joppa Road into a roundabout. Prior to the roundabout, this perilous intersection was home to many serious crashes. Now this roundabout is safer.

Roundabouts continue to grow on MDOT SHA-maintained roads. The number is at 88 to date, with several underway or planned. There are nearly 200 throughout Maryland including State and local roads. The roundabout idea came to America from the United Kingdom in 1905 in New York City. 

For more information about roundabouts in Maryland, click here.