Skip to Content
Streetsblog USA home
Streetsblog USA home
Log In
Bicycle Safety

Zig Zag Road Striping Calms Traffic in Virginia

Virginia Department of Transportation installed these zig zag pavement markings to caution drivers about the potential for pedestrians and cyclists by a popular trail crossing. Photo: Virginia Department of Transportation
Virginia DOT installed these zig zag markings to caution drivers approaching the intersection of a popular walking and biking trail. Photo: Virginia DOT
Virginia Department of Transportation installed these zig zag pavement markings to caution drivers about the potential for pedestrians and cyclists by a popular trail crossing. Photo: Virginia Department of Transportation

At 11 points in northern Virginia, the familiar straight dashed lines on the road gives way to a series of zig zags. The unusual markings, the result of a pilot project from the Virginia Department of Transportation, are meant to alert drivers to be cautious where the Washington and Old Dominion (W&OD) Trail intersects with the road -- and bicyclists and pedestrians frequently cross.

After a year-long study of this striping treatment, Virginia DOT officials say the markings are effective and should become part of the Manual on Uniform Traffic Control Devices -- the playbook for American street designers.

This photo shows another style of zig zag pavement marking tested in Virginia. Photo: VDOT
This photo shows another style of zig zag pavement marking tested in Virginia. Photo: VDOT
This photo shows another style of zig zag pavement marking tested in Virginia. Photo: VDOT

VDOT found the zig zag markings slowed average vehicle speeds, increased motorist awareness of pedestrians and cyclists, and increased the likelihood that drivers would yield. They also noted that the effects of the design change didn't wear off once motorists became used to the it -- they still slowed down a year after installation.

VDOT says the results indicate that zig zag markings are a more cost-effective solution for conflict points between trails and high-speed roads than the current treatments: flashing beacons placed above the road or off to the side.

The zig zag concept was imported from Europe. It is currently used in only two other locations in North America: Hawaii and Ottawa, Ontario. It was one of more than a dozen European traffic management techniques VDOT zeroed in on to test locally.

The zig zag markings reduced motorist speeds approaching the trail at Belmont Ridge Road, according to a VDOT study. The effect was long lasting.
The zig zag markings reduced motorist speeds approaching the trail at Sterling Road by about 5 mph, according to VDOT. The effect remained strong over time.
The zig zag markings reduced motorist speeds approaching the trail at Belmont Ridge Road, according to a VDOT study. The effect was long lasting.

The W&OD trail is a popular route for both recreation and commuting in the D.C. metro area. Between 2002 and 2008, there were 21 collisions involving cyclists and two involving pedestrians along the trail, which intersects with major roads at 70 points along its 45-mile path in Fairfax and Loudoun counties in Virginia.

The effect of the zig zag markings was measured using speed radars over the course of a year. Feedback from motorists, cyclists, and pedestrians was also collected using online surveys. While the survey did not come from a random sample, 65 percent of drivers said they were more aware because of the markings and 48 percent said they liked them. The zig zags were also popular with cyclists; 71 percent said the markings affected driver behavior.

Said one respondent: "Drivers rarely stopped before the markings were installed. Since installation, they stop much more often."

Stay in touch

Sign up for our free newsletter

More from Streetsblog USA

Friday’s Headlines Got Served

Another day, another GOP lawsuit trying to overturn a Biden administration climate change rule.

April 19, 2024

Talking Headways Podcast: Charging Up Transportation

This week, we talk to the great Gabe Klein, executive director of President Biden's Joint Office of Energy and Transportation (and a former Streetsblog board member), about curbside electrification.

April 18, 2024

Why Does the Vision Zero Movement Stop At the Edge of the Road?

U.S. car crash deaths are nearly 10 percent higher if you count collisions that happen just outside the right of way. So why don't off-road deaths get more air time among advocates?

April 18, 2024

Donald Shoup: Here’s a Parking Policy That Works for the People

Free parking has a veneer of equality, but it is unfair. Here's a proposal from America's leading parking academic that could make it more equitable.

April 18, 2024

Thursday’s Headlines Turn Up the Heat

Whether you realize it or not, climate change is here, and not just in the form of natural disasters.

April 18, 2024
See all posts