Rusted traffic light pole falls onto sidewalk in Chicago's West Loop
CHICAGO (CBS) – A rusted traffic light was spotted Thursday after falling onto the sidewalk in the West Loop.
The traffic light pole once towered over the intersection at Washington and Morgan, but was lying on the sidewalk on Thursday. Rust appeared to consume the pole's base.
Former Illinois Institute of Technology professor Sammy Tin has worked with CBS News Chicago Investigators on previous stories involving light poles that had fallen because of corrosion. CBS News Chicago showed Tin two photos of the downed traffic light at the southwest corner of Washington and Morgan.
Tin, now a professor and head of the Department of Material Science and Engineering at the University of Arizona, gave his opinion on the incident.
"There was definitely a significant amount of corrosion that I noticed along the base and in the pictures that you provided," he said. "You could definitely tell that the corrosion basically reduced the cross sectional area of the metal, and that is probably what caused failure of the pole."
He added that the service life of a typical light pole is about 30 to 40 years.
In 2017 and 2018, the city had visual inspections done of every street light pole to check their conditions. CBS News Chicago obtained the data. It appeared the study did not include traffic light poles like the one that fell this week, even though the pole showed significant rust at the base.
Tin said ultrasonic inspection should be used on traffic light and light poles to check the thickness of the steel that's under the rust. The method is more costly and time consuming than a visual inspection, but it makes a big difference.
"I guess light poles that have some evidence of damage that has not been properly addressed," Tin said. "You know, I think a more advanced inspection technique is definitely more warranted."
The Chicago Department of Transportation said the traffic light pole was inspected on March 25 and had minor surface rust. CDOT also said it's possible an unreported hit and run could have compromised the pole.
