Here’s why Broad River interchange over I-20 has an ‘unconventional’ design
The unusual, curving traffic pattern where Broad River Road crosses Interstate 20 isn’t a temporary detour — it’s the long-term design.
Brad Reynolds, director of the Carolina Crossroads project for the South Carolina Department of Transportation, said the interchange’s “unconventional” layout was shaped both by construction constraints and by an effort to improve safety and congestion at one of the region’s busiest crossings.
“It is a little unconventional with the offset coming across the bridge,” Reynolds told The State. That offset, he said, was needed because there was an existing bridge at the site and the contractor had to keep traffic moving on Broad River Road while building the new bridge.
Even so, Reynolds said the design is intentional and is part of the broader Carolina Crossroads project, the state’s sweeping set of interstate upgrades in the Columbia area.
Why it looks different
Drivers have described the Broad River Road/I‑20 crossing as disorienting: the roadway bends, the lanes feel shifted and the signals are positioned differently than at a more traditional interchange.
Breanna Corey, who lives on Broad River Road and regularly travels across the interchange, said the updated construction route is “absolutely terrible.”
“I feel like they could do better with the signs by adding a little bit more direction,” she said. “I go through here a lot because I stay right down the road, and it’s bad. The stop lights too, they literally take forever.”
Reynolds said the curvature is largely the result of the bridge offset. He emphasized that the corridor is designed for low speeds, is signed to guide motorists and requires drivers to pay close attention as they travel through.
Senazha Fischer, another regular commuter across the interchange, said she has mixed feelings about the new design, noting that while she believes it’s dangerous, the pattern adds a certain appeal to the area.
“I think the (new pattern) is nicer and makes Broad River look more fancy, but I feel like it’ll cause more accidents because the road, itself, just has too much going on at once,” Fischer said, who’s lived in the area for the past five years.
Broad River Road carries a large amount of traffic over I‑20, Reynolds said, and the corridor had significant congestion before the new interchange type was installed.
Traffic crash data in the area will not become available until after one year from the time the new design was implemented, based on data collection practices by the South Carolina Department of Public Safety.
Removing left turns — and some high‑risk crashes
One of the biggest changes, Reynolds said, is the removal of certain left‑turn movements that can lead to severe wrecks.
By routing traffic, so vehicles can come off the interstate and “free flow” over the overpass — then cross back to the correct side of the roadway beyond the interchange — the design reduces the number of locations where drivers would otherwise turn across oncoming traffic.
“Historically, that is one of the highest crashes that we have is at intersections — the left turn movements,” Reynolds said, adding that those crashes also tend to be among the most severe.
He compared the learning curve to modern roundabouts: unfamiliar at first, but safer once drivers understand how to navigate them.
How SCDOT chose the design
Reynolds said the Broad River Road interchange was procured through a “design‑build” process.
SCDOT first identified the goals for the corridor — including safety concerns and “level of service,” or the ability to move a certain number of vehicles through the area — then shortlisted qualified teams of designers and contractors, he said.
Those teams proposed solutions to meet the state’s goals, and SCDOT scored the proposals using both cost and quality initiatives. The team with the highest total score moved forward, Reynolds said, and the agency evaluated the proposal along the way to ensure it met the requirements.
Part of the larger Carolina Crossroads program
Reynolds said the new Broad River Road interchange is “a piece of a much larger program,” referring to Carolina Crossroads, also known as Malfunction Junction.
The project, which features four phases in total, began in November 2021.
Phase one, which created a new full access interchange at I-126 and Colonial Life Boulevard; removed the Bush River Road interchange at I-26; and lengthened the I-26 eastbound exit ramp to US 378/Sunset Boulevard is 99% complete, according to the department.
It was in Phase two that the Broad River interchange at I-20 was updated.
Phase two also removed the shared ramp with Garner Lane; and widened I-20 to prepare for additional improvements in later phases.
“All these roads underneath this new interchange are ultimately going to feed into” the broader set of interstate improvements connected to the program, Reynolds said.
What’s next — and what’s unknown
Reynolds said it is still too early to cite whether the new configuration has reduced crashes, and that safety performance will be evaluated in the future.
The current configuration opened around June of last year, according to Reynolds.
In the meantime, Reynolds urged drivers to follow posted signs and stay alert through the corridor as the traveling public becomes more familiar with the nontraditional layout.
This story was originally published March 18, 2026 at 5:00 AM.
