Spotlight on Active Traffic Management (ATM) Strategies

Active Traffic Management (ATM) is the ability to dynamically manage recurrent and non-recurrent congestion based on prevailing and predicted traffic conditions. As a key component of Intelligent Transportation Systems (ITS), ATM strategies enhance roadway efficiency, improve safety, and optimize traffic flow in real time. These strategies rely on integrated systems, advanced technologies, real-time data collection and analysis, and robust communication networks to manage freeway and arterial traffic flow dynamically.

Learn more about FHWA’s Active Traffic Management approaches at https://ops.fhwa.dot.gov/atdm/approaches/atm.htm.

Aerial view of cars in an intersection (Source: FHWA)

Adaptive Traffic Signal Control

Transit bus driving through a signalized intersection (Source: Shutterstock/Ryan DeBerardinis)

Transit Signal Priority

Traffic light for highway on ramp. Stop here on red.

Adaptive Ramp Metering

Dynamic message sign showing "stopped traffic ahead" message (Source: FHWA/Texas A&M Transportation Institute)

Cars driving on a highway under dynamic signs showing the speed limit (Source: FHWA)

Variable Speed Limits

Cars driving on a bridge under dynamic lane signals (Source: Shutterstock/Khairil Azhar Junos)

Dynamic Lane Use Control

Success Stories

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In Colorado Springs, the Adaptive Traffic Management System Using Radar, LiDAR, Video Analytics, and “Digital Twin” of Intersection Operations Estimated Reductions in Traffic Delay Up to 23.7 percent.

Colorado Springs, Colorado, United States

Date Posted: 2025-08-28

Deployment of an Active Traffic Management System with a Dynamic Shoulder Lane in Michigan Reduced Crashes by 17 Percent and Yielded a Benefit-Cost Ratio of Up to 3.01.

Ann Arbor, Michigan, United States

Date Posted: 2022-05-25

A Variable Speed Limit (VSL) System Using an AI-Based Algorithm on I-24 in Nashville Reduced Traffic Speed Variations by 32.7 Percent to Improve Safety with Limited Impacts on Vehicle Hours of Delay (VHD).

Nashville, Tennessee, United States

Date Posted: 2024-04-23

Queue Warning Implemented as Part of an Integrated Active Traffic Management System Estimated to Reduce Travel Time up to 5.6 Percent and Reduce Crash Risk up to 28 Percent.

Orlando, Florida, United States

Date Posted: 2022-11-30

California's Coordinated Ramp Metering and Variable Speed Advisory Study Found a 14.56 Percent Decrease in Daily Average Number of Accidents.

Date Posted: 2024-11-29

Massachusetts Bay Transit Authority’s Signal Priority Implementation Led to Buses Spending an Average of 21 Percent Less Time Waiting at Red Lights.

Boston, Massachusetts, United States

Date Posted: 2025-05-30

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Image Credits

Queue Warning, FHWA/Texas A&M Transportation Institute, https://ops.fhwa.dot.gov/publications/fhwahop20009/index.htm
Transit Signal Priority, Shutterstock/Ryan DeBerardinis, https://www.shutterstock.com/image-photo/busy-street-scene-people-bus-taxi-2101893226
Variable Speed Limits, FHWA, https://highways.dot.gov/safety/proven-safety-countermeasures/variable-speed-limits
Adaptive Ramp Metering, Shutterstock/Red Herring, https://www.shutterstock.com/image-photo/traffic-light-highway-on-ramp-stop-1960929496
Adaptive Traffic Signal Control, FHWA, https://www.fhwa.dot.gov/innovation/everydaycounts/edc-1/asct.cfm
Dynamic Lane Use Control, Shutterstock/Khairil Azhar Junos, https://www.shutterstock.com/image-photo/maryland-us-sept-10-2025-traffic-2681220323