Flashing yellow signals come to I-270 ramps ahead of metering system

Maryland road crews are taking the next step toward rolling out ramp metering along Interstate 270 this week, turning on the yellow traffic signals that will eventually control the flow of traffic onto one of the state’s busiest roadways.

On Tuesday morning, crews began uncovering and turning on the flashing signals on 23 ramps along southbound I-270 in Montgomery and Frederick counties, starting at Md. Route 80 and working their way south, the Maryland Department of Transportation’s State Highway Administration said.

Meters will flash yellow to alert drivers that the new metering system is coming. The turn-on process, which depends on the weather, will take about a week to complete.

MDOT said that on Tuesday, the locations with traffic signals transitioned to yellow flashing mode include:

• MD 80 TO I-270 SB – EXIT 26
• MD 109 TO I-270 SB – EXIT 22
• MD 121 SB TO I-270 SB – EXIT 18
• MD 121 NB TO I-270 SB – EXIT 18
• MD 27 WB TO I-270 SB – EXIT 16
• MD 118 SB TO I-270 SB – EXIT 15
• MD 118 NB TO I-270 SB – EXIT 15

And starting at 9 a.m. Wednesday, MDOT said it anticipates switching the following locations to yellow flashing mode:

• MD 124 TO I-270 SB – EXIT 11
• MD 117 TO I-270 SB – EXIT 10
• I-370 TO I-270 SB – EXIT 9

The work is weather dependent, MDOT said.

The final stage comes Sept. 15, when the signals, which are the first ramp meters in Maryland, are fully activated.

The ramp metering system is part of a series of measures designed to relieve congestion on I-270 in the short term.

When metering is in operation, flashing beacons earlier on the ramp will prompt drivers to be prepared to stop. At the end of the ramp, drivers will encounter an overhead traffic signal and must wait for a green light, before merging, one car at a time per lane, onto the interstate.

“Our administration is committed to providing solutions to address congestion on I-270,” Gov. Larry Hogan said in a release. “Ramp metering is an innovative approach to reduce travel times, improve the quality of life for residents and spur economic growth in Frederick and Montgomery counties and across the National Capital Region.”

In June, crews installed the meters on the ramp from northbound Maryland 118 to southbound I-270, which allowed crews to test out the system in a live traffic environment.

Once operational, the ramp meters will run from 4 a.m. till 11 p.m. each day and are expected to be active during peak traffic. The system also has the capability of detecting the length of the queue waiting to merge so ramps don’t back up to arterial roads.

“Ramp metering is an innovative, cost-effective tool to improve safety, ease congestion and make daily commutes more reliable throughout the corridor,” MDOT Secretary Greg Slater said in a statement. “The system is new to Maryland, but in other parts of the country ramp metering is a proven tool that works to improve traffic flow and help drivers merge more safely and easily onto busy highways.”

There are plans to install even more meters in the future.

In addition to the 23 southbound I-270 ramps being activated this week, Maryland transportation officials plan to install ramp metering on another 22 ramps onto northbound I-270 in 2022. That would bring a total of 45 ramps at 18 interchanges by the end of next year.

Jack Moore

Jack Moore joined WTOP.com as a digital writer/editor in July 2016. Previous to his current role, he covered federal government management and technology as the news editor at Nextgov.com, part of Government Executive Media Group.

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