SEBRING — If you stopped today at the intersection of Sebring Parkway and Scenic Highway, and the red light changes green for you, thank the influence from above.
Specifically, an overhead sensor saw whether or not you had oncoming cross traffic, and tripped the controls for the traffic signals if you didn’t.
It’s the only sensor like it that the county has in use right now, County Engineer Clinton “Gator” Howerton Jr. said, and took two months to get because of high demand.
The county spotlighted the device with a photo on social media this week. Howerton said these sensors are mounted to existing poles and can detect when vehicles approach the intersection, allowing the signal to change when appropriate.
“If you happen to see these new devices sticking up at an intersection, these are not ‘red light cameras,’ but are just there to detect approaching vehicles much like the existing wire loops do that are placed under the asphalt,” the county’s social media post stated.
Comments on the post questioned how much it would cost to replace if a car or hurricane knocks down the pole. People also asked what was the benefit of an overhead sensor versus the existing electromagnetic loops in the roadway.
In a conversation with the Highlands News-Sun, Howerton explained why the county is testing this new device, starting with what makes them high demand? Convenience, he said, or rather not having to inconvenience motorists.
He said traffic loops require a four-person road crew to spend two days closing lanes, cutting pavement, installing loops in the grooves, running conduit to the “control closet” — the traffic signal relay box — and testing the system.
The overhead camera and motion sensor device can be installed in one afternoon by a single worker in a bucket truck and covers the whole intersection.
It eliminates the need to close lanes or cut up the pavement, which can let water under the pavement and cause the pavement to crack, requiring more maintenance.
How much does it cost? The device actually costs more than pavement-mounted vehicle detection loops: $13,000 versus $10,000 for the loops at a four-lane divided highway and two-lane feeder road crossroad, such as where it is now.
“Everything we do costs a lot,” Howerton said, because of safety requirements.
However, Howerton said, the overhead device can do the job of all the loops, and do a better job detecting small vehicles, like motorcycles and scooters.
While both systems are susceptible to lightning strikes, Howerton said, the device also is easier to replace and won’t require crews to close lanes.
Traffic can keep moving, he said.
If it works out, Howerton said he’d probably move the device to the new three-way intersection planned for the 90-degree turn once Sebring Parkway Phase III gets completed sometime next year.
It could save time on that project, which already has a deadline of Dec. 31, 2019.
Howerton said installing loops on new pavement requires crews to lay asphalt, let it cure 20 days, then come back and cut the hardened surface.
Aside from that extra time, installing loops at a new intersection would hamper traffic right after motorists get used to using the new road.
For now, the overhead sensor is operating the Sebring Parkway/Scenic Highway intersection. Motorists might have to look up to see it; once they are at a stop, of course.