Work kicked off May 2 on a nearly $16 million project to add a series of roundabouts in the Gilberts Corner area of Loudoun County, part of a broader project to slow traffic and ease congestion along a 20-mile stretch of the increasingly busy U.S. 50 corridor.

The work, being paid for largely with federal money, will add four roundabouts, or circular intersections, in and around Gilberts Corner -- the U.S. 15 and U.S. 50 intersection.

One will replace the traffic light at that intersection; another will be east of the junction at U.S. 50 and Watson Road; two more are planned for either end of a new connector road linking U.S. 15 and U.S. 50. The roundabouts will be the first in Virginia on a major highway.

Popular overseas and in other parts of the country, including Maryland, roundabouts, according to state transportation officials, are a cheaper and less obtrusive alternative to costly interchanges, which can cost five times as much to build.

Officials also tout roundabouts' safety record. According to a 2001 study by the Insurance Institute for Highway Safety, converting traditional intersections to roundabouts reduced crashes by 40 percent. There were 23 wrecks at U.S. 15 and U.S. 50 in 2007, according to the Sheriff's Office.

Work on the Gilberts Corner project, according to the Virginia Department of Transportation, will get under way immediately and will start with the two-lane connector road and its two roundabouts. This new road will allow some traffic to bypass Gilberts Corner altogether.

Meanwhile, work on the roundabout at 15 and 50 will begin next spring. The entire project will be completed by December 2009, officials said.

In the meantime, VDOT says it will undertake an outreach program to educate motorists on how to best maneuver through roundabouts. A DVD with instructions on how to drive through one safely is already available.

“There was some, 'Oh my, there are going to be all sorts of wrecks,'” said Betsy Allen Davis, mayor of nearby Middleburg. “But like anything new, we will all have to learn it.”

Tucker Withers, owner of the Little River Inn in Aldie, said he has driven through roundabouts in New England and in Europe with little difficulty.

He applauds the one planned for 15 and 50 because, as he said, it will replace the traffic light that is a common source of backups, some all the way into Aldie, which is more than a mile west of Gilberts Corner.

“I feel for the people who have to drive on 50 to work,” he said. “So I think [roundabouts] are a good thing. It's at least worth a shot.”

The Gilberts Corner roundabouts are one of three traffic-calming projects planned for U.S. 50. In Upperville, work wrapped up in December that added medians and landscaping to slow vehicles passing through that community, while similar work will begin in Aldie in 2009.

Attending a groundbreaking last Friday were Sen. John Warner (R), U.S. Rep. Frank Wolf (R-10th), Supervisor Jim Burton (I-Blue Ridge) and representatives from VDOT and the Route 50 Task Force, a citizen group that spearheaded the planning of the three traffic-calming projects.