Building the foundation for Smart Traffic Management in Louisville

Louisville Metro is an expansive area that covers 380 square miles. More importantly to the Public Works Traffic department, drivers in Louisville travel over 500,000 miles per day on our local roads (that is over 20 times the distance around the Equator). To facilitate this large number of miles traveled, the PW traffic team maintains the 1020 traffic signals and traffic timing plans, the red/green light patterns, all over our consolidated city-county jurisdiction with the goal of moving people and vehicles efficiently, effectively, and safely throughout our community.

Louisville, like many metros in the United States, has a mixture of urban, inner-ring suburbs, and traditional suburbs. This means that running fiber optic cable, the preferred conduit for communicating with traffic signals, to all of the intersections throughout the metro area is not financially feasible. The connectivity that comes with a fiber connection allows for the traffic signal maintenance team to make near real-time changes to the signals from the traffic control center in downtown Louisville. Traffic signals outside of our fiber optic footprint have to be manually adjusted on-site at each intersection. This re-timing process requires lots of hands-on and on-site time for both traffic engineers and crews. Additionally, because the signals are not in direct communication with the command center downtown, they rely on citizens to report that an intersection is on “flash”, or isn’t working properly, to know about issues with signals.

Old v. New Process for Fixing Traffic Signals on “Flash”

This capability gap dramatically reduces their ability to serve the community. To remedy this capability gap, there were really only two options: hire a lot more people or find a technology solution, better known as a Smart City solution, to close the gap. After a research and discovery process, we decided to go with a commercially available and, if scaled, economically feasible Smart City solution. We found a willing partner in Verizon and their partner, Digi, for a no-cost pilot project to implement a Smart City solution to close the Public Works Traffic’s capability gap.

The project put cell-phone like communications platforms on 14 signals on an outlying corridor. While we are still working out the kinks, the units have been deployed and have (more often than not) given the traffic team the ability to communicate with these signals in near real-time. This means signal retiming can be done in a day rather than over the course of two weeks. Also, they are informed when signals go down, which allows them to deploy a crew to fix it faster more quickly thus preventing unnecessary congestion on our roads.

If, or more likely when, this project it is scaled it will expand to over 300 signals in our community. The Smart City solution will then have given to Public Works Traffic team the ability to communicate in near real-time with 30% of the signals that they previous had to manual reconfigure and rely on citizens to report outages. This increased capability will allow them to maximize their productivity and resources currently available to them rather than having to add personnel. This capability becomes even more impactful as we are able to harness the big data from our partners like KYTC and Waze to use real-time data analytics to optimize our traffic patterns for safer and quicker commutes in our community.
For more information contact Ed Blayney at edward.blayney@louisvilleky.gov or follow him on twitter (@edblayney)