IE 11 Not Supported

For optimal browsing, we recommend Chrome, Firefox or Safari browsers.

Adaptive Signaling to Improve Major South Carolina Arteries

New traffic signal technology may help alleviate traffic congestion in the Rock Hill area. The smart signals react to traffic conditions in real time and adjust to optimize the flow of traffic.

Traffic light
(TNS) — One massive road construction project is days from completion and several others are on track for 2021.

Then, there are the traffic signals.

Berry Mattox with the South Carolina Department of Transportation updated elected and planning officials earlier this month on a variety of road projects in urbanized York and Lancaster counties. Projects span Rock Hill, Fort Mill, Indian Land and other spots served by the Rock Hill-Fort Mill Area Transportation Study.

Mattox said his department has taken several calls on one improvement that's already been made.

Adaptive traffic signals have been installed since August at seven intersections along the S.C. 160 corridor from Sutton Road to U.S. 21 in Fort Mill. The smart signals are on either side of the S.C. 160 interchange at I-77.

"They've been installed," Mattox said. "They're operational. We do think this will help."

The smart signals react in real time to traffic conditions, so they may skip signals or have longer green lights. A left-turn green signal coming out of Kingsley might, for instance, come more often or last longer at rush hour than at off hours. Heavier traffic at Baxter might cause a longer light heading toward the interstate in the morning than early afternoon.

The idea is to keep the most traffic moving, as often as possible. Drivers have noticed the change. Hence the phone calls.

"The signal phasing is not always what you expect," Mattox said. "They make different decisions to what you may be used to."

Mattox said the calls in a way are proof the almost $490,000 in signal upgrades are working. SCDOT will get a better picture once full traffic resumes after the COVID-19 pandemic. The agency will be able to adjust signals as needed.

David Hooper, RFATS administrator, said the smart signals are useful not just at peak morning and evening rush hour. They're also helpful, he said, at lunch.

"That is also a time of heavy congestion," he said.

The Kingsley and Baxter areas in particular can have traffic issues, especially with the large and growing employment base at Kingsley.

"We heard time and time again that they couldn't even go over to Chick-fil-A and be back in an hour," Mattox said.

Along with the traffic lights, there are several other large construction projects in the works:

— The $21.5 million widening of S.C. 160 in Lancaster County is just days from completion. Blythe Development Co. is the contractor. The expected completion date is Dec. 1. Mattox said there may be some small details that linger, like a traffic signal that may lag a couple of weeks. The project should be done in full by the end of the year.

"It's had its fair share of delays," Mattox said.

S.C. 160 will be widened from Possum Hollow Road to the York County line at Sugar Creek. It will be five lanes from Possum Hollow to Rosemont Drive and three lanes from Rosemont to Sugar Creek. There will be an additional lane of travel each way, plus a center lane, compared to the road prior to construction.

— The interchange at I-77 and S.C. 160 is listed as a $76 million project. York County applied for and received state infrastructure bank money ($49.6 million) for the Fort Mill project. SCDOT held a public meeting in January and has settled on an option for a directional interchange with two bridge crossings over the interstate. Widening of S.C. 160 from Sutton Road to U.S. 21 is included.

Right-of-way should wrap up next year. Construction funds should be in place by 2022. The work would then go for bid ahead of construction.

"We're on schedule to start construction summer to fall 2022," Mattox said.

— The other interchange to get infrastructure bank funding through the county application is I-77 and Cherry Road/Celanese Road in Rock Hill. It involves improvements at exits 82A, B and C. The $38.49 million project doesn't yet have a determined schedule. Of the total, more than $32 million comes from the infrastructure bank and the county local match portion.

The Rock Hill interchange will happen after the Fort Mill work, which could mean costs "well above" what transportation leaders list now, Hooper said.

"We have to assume that the total project cost on this will be higher," he said.

— Work at Celanese and India Hook roads in Rock Hill should begin construction next year. The $7.63 million project will add and lengthen turn lanes at the intersection. Right-of-way is done. Construction funds should be available in April. Construction bids would follow in June.

The project timeline is similar to SCDOT work at Pleasant Road and Carowinds in Fort Mill, and at U.S. 521 and Marvin Road in Indian Land.

"They're all kind of on the same schedule," Mattox said.

— The Pleasant and Carowinds intersection work was intentionally delayed by SCDOT work due to other projects in the area, like the ongoing interchange reconfiguration at I-77 and Gold Hill Road. SCDOT wanted to allow routes of traffic that avoid construction areas. With the traffic dropoff from COVID-19, that delay may not have been needed.

"We actually probably would have been OK," Mattox said.

Work should go to construction bid in June 2021. More turn lane capacity will be added to the intersection. The project is listed now at $2.1 million, but Mattox said that amount will increase.

— A $1.86 million project to add a turn lane at Clebourne and North White streets in Fort Mill is almost complete. Cherokee, Inc. is the contractor. The completion date is Dec. 31. The right turn lane from Clebourne onto U.S. 21 Business will improve traffic at one of the main downtown choke points in town.

— Intersection work at U.S. 521 and Marvin Road should go to bid this coming spring. The $3.64 million project has had schedule delays. The more than $2.8 million construction budget is up about five times from the initial, placeholder amount. Right-of-way is wrapped up. Construction funds should be ready in March, and construction bids in May. Construction should begin summer 2021.

A new southbound left turn lane and right turn onto Marvin are part of the project, along with upgraded traffic signals.

©2020 The Herald, Distributed by Tribune Content Agency, LLC.