Growing grid
UTC plans to expand the smart corridor to all of downtown
In an effort to gather more data on traffic and air quality, the University of Tennessee at Chattanooga is planning to expand its smart corridor along M.L. King Boulevard to all of downtown Chattanooga in the coming years.
The smart corridor is a group of sensors tracking traffic and air quality at 13 intersections across a 1.2-mile stretch of M.L. King Boulevard from Highway 27 to Central Avenue.
When expansion is complete, the sensors, which currently collect more than 2 billion data points a day, will be at more than 100 signalized intersections covering all of downtown.
The data from the corridor is gathered and researched by UTC’s Center for Urban Informatics and Progress, which started in 2018.
The data is used to improve traffic safety, Mina Sartipi, founding director of the center, said in an interview.
“The original goal, defined by the city, was to improve pedestrian and cyclist safety,” Sartipi said. “Where are the areas that the vehicles are getting too close to pedestrians or cyclists, like the left turns or right turns, or any of those, that would potentially put a person, which we call vulnerable road users, in danger?”
No personally identifiable information is gathered, Sartipi said.
Among the data Sartipi’s team collects is the number of vehicles on the road, how long pedestrians are waiting to cross and metrics related to traffic flow, she said.
The center is in the process of adding sensors perpendicular to M.L. King Boulevard on a 2.2-mile stretch of Highway 27.
“It will be very similar technology but deployed up on the highway,” Austin Harris, the center’s director of operations and chief engineer, said in an interview. “That will allow us to look at different use cases and driver behavior. A lot of the applications are very different on the highway versus urban mobility.”
Off the highway, sensors at an additional 27 intersections downtown have been funded as of January 2023. Those intersections include those parallel to M.L. King Boulevard on McCallie Avenue from Georgia Avenue to the tunnel under Missionary Ridge.
Sensors will also be added to intersections farther along M.L. King Boulevard past Central as well as intersections on Market and Fourth streets.
The sensors should be operational at some point within the next two years, Sartipi said.
FUNDING AND COSTS
Installation at each intersection, depending on variables at each crossing, typically costs about $20,000, Harris said.
To operate, the corridor has received funding from the National Science Foundation and the U.S. Department of Transportation, Sartipi said in an email.
In 2020, the Chattanooga City Council approved more than $55,000 in city funds to the project.
City spokespeople did not respond to an emailed request asking if additional funding from the city has gone toward the corridor.
PRIVACY
The sensors at each intersection along the smart corridor collect video, but the images are not captured live. The video itself is dark and grainy at a low resolution.
Essentially, the Center for Urban Informatics and Progress knows when a pedestrian, cyclist or vehicle enters an intersection, but center officials have no way of personally identifying anyone.
The center can also create animated models — with blobs of various colors indicating which type of traffic user — based on the data, but none of it can be used to identify anyone.
No data of that nature is collected or stored, Sartipi said.
“We did work to communicate with the neighborhood associations, citizens and business owners just to basically communicate what we are trying to do,” Sartipi said. “What we are not doing is watching or listening to people.”
When asked if any information is shared with law enforcement agencies, Sartipi said, “We don’t store anything.”
“There have been cases that people had reached out to us, that there was an accident or there was something that they want to have access to video,” Sartipi continued. “We really keep telling them that we really don’t have anything to share.”
BENEFITS OF THE SENSORS
The center’s data has been used to help improve public safety, Sartipi said. Recommendations have been made to the city based on the data.
“We have identified areas that have higher risk of accidents,” Sartipi said. “Changes had been done to some of the lighting time for traffic lights. Crosswalks have been added throughout the corridor because we had identified areas that people were crossing in the mid blocks.”
Outside the corridor, the city has seen an increase in the pedestrian deaths, the Chattanooga Times Free Press reported earlier this year.
The sensors have also helped with air quality and fuel efficiency, Osama Osman, chief scientist at the Center for Urban Informatics and Progress, said in an interview.
He said the center has used the data to reduce stops at intersections, improving traffic control and reducing gas consumption used during acceleration. In total, fuel efficiency has increased by up to 20%.
“If you turn that into money, that’s a lot of money. That’s one thing,” Osman said. “The other thing is improving travel time for people in the corridor.”