September 8, 2021

MDOT SHA to Turn on Full-Color Ramp Metering Signals at 18 Interchanges Along Southbound I-270 on Wednesday, Sept. 15

The Maryland Department of Transportation State Highway Administration (MDOT SHA) will fully activate new ramp meters on 23 ramps to southbound I-270 in Montgomery and Frederick counties on Wednesday, Sept. 15, weather permitting. The state agency said ramp metering is a part of the I-270 Innovative Congestion Management (ICM) project to help improve safety, reduce congestion and save drivers up to 30 minutes on morning commutes between Frederick and I-495 (Capital Beltway).

This is the first system of its kind to be implemented in Maryland.

Ramp metering uses traffic signals and sensors to manage traffic flow entering the highway. The system balances highway demand and capacity, maintains optimal highway operation and reduces congestion. The ramp metering signals will have the capability to operate between 4 a.m. and 11 p.m. daily and are anticipated to be active during peak traffic hours and when I-270 experiences traffic congestion.

Signals at the end of the ramps have been flashing yellow for about a month to alert motorists that activation of ramp metering is coming. When ramp metering is in full operation, motorists will see a warning sign with flashing beacons and should slow down, watch for queued vehicles and be prepared to stop at the stop line just prior to the highway entrance. Once the signal turns green, a driver may proceed and merge onto the highway. When ramp metering is not in operation, beacons will be dark and the traffic signals will flash yellow, allowing motorists to proceed without stopping.

Motorists are advised to use caution and reduce their speeds approaching the traffic signal, as there may be stopped vehicles waiting to merge onto the highway. The system also detects the length of vehicles in queue to help ensure ramps do not back up onto arterial roadways.

While a first for Maryland, MDOT SHA said that ramp meters have been used elsewhere as a proven, cost-effective tool to help improve safety and efficiency and reduce congestion. Ramp metering is one piece of the I-270 ICM Project that Governor Larry Hogan announced in 2016 to provide congestion relief and improve travel times throughout the 34.4-mile I-270 corridor from I-70 to I-495.