Gateway Green Light

Thank you to the East-West Gateway Council of Governments for sharing their 2016 Outstanding Local Government Achievement Award Video on Gateway Green Light with us for this website!

Gateway Green Light is a cooperative effort to improve the coordination of traffic signals throughout St. Charles County. The program helps synchronize traffic signals on streets throughout the county, especially those that cross city limits. This reduces unnecessary delays, improves traffic flow and cuts emissions that contribute to ozone pollution.

How It Works


The state and local governments that own traffic signals in the area are working together to make sure that the timing plans for the intersections on major routes are coordinated for more efficient flow of traffic.

Although existing equipment is used wherever possible, some new communications equipment and software, and new signal controllers were installed so the traffic signals on the system can communicate with each other and with a central operations center. This equipment and software help keep the traffic signals in sync with new timing plans. A total of 120 miles of fiber optic cable links observation cameras and 337 road signals to the system. 

The program seeks to provide motorists with real-time information on roadway conditions and travel times through the use of dynamic message boards and travel time detectors installed in upcoming construction phases. As Gateway Green Light infrastructure continues to expand, benefits to the public will continue to increase.  

Helping Traffic Flow


Depending on factors like the length of a trip and the number of traffic lights, Gateway Green Light could save seconds or even minutes for someone driving on a coordinated route. Since thousands of vehicles travel along each road on a weekday, this could add up to noticeable improved traffic flow, especially during rush-hour periods in the morning and afternoon.

Participating Government Organizations


The following government organizations are working together to deliver Gateway Green Light:
  • City of Cottleville
  • City of Dardenne Prairie
  • City of Lake Saint Louis
  • City of O'Fallon
  • City of St. Charles
  • City of St. Peters
  • City of Weldon Spring
  • City of Wentzville
  • Missouri Department of Transportation
  • St. Charles County
Learn more about the program in the Connection newsletter. Stay tuned for more information on Gateway Green Light! The video clip titled "Keeping Las Vegas Moving" from America Revealed, a Public Broadcast Station (PBS) TV show, demonstrates how similar technology on a larger scale improves transportation and saves tax dollars.