The interchange of the 57 and 60 freeways is a massive merging of 17 lanes of freeway into just 14 lanes. When you add big rigs to the mix, it can get ugly.
Data from The American Transportation Research Institute even shows it's the worst truck bottleneck in the state and the fourth worst in the country.
The numbers prove it. According to the CHP, in L.A. County, 6.8% of crashes involve big rigs. At the 57/60 interchange, it's about double the amount at 13.7%. Last year alone, there was an accident a day in this area.
That's why the neighboring cities of Diamond Bar and City of Industry have teamed up with LA Metro and Caltrans to come up with a solution, led by the San Gabriel Valley Council of Governments.
"We have done some preliminary work. Exits on the Grand Ave. exit have already been improved. And we adjusted Brea Canyon exit on the 60 Freeway," said Mark Christoffels, the agency's chief engineer. He's been spearheading relief efforts since the groundbreaking four years ago.
In a couple of years, drivers will notice significant construction when crews add lanes to the 60 eastbound. That'll require them to take down the Grand Avenue overpass and reconstruct it, meaning a full overnight closure at some point.
"We're gonna try to maintain freeway traffic as we build it, but yes construction will be a sore spot for the motorists as we work through it," said Christoffels.
The $400 million project is partly funded by taxpayers via the passage of Measure M and a recent increase in the diesel tax, but they're hoping for additional funds via federal grants.
"I guess it's good and bad news to get recognized as the fourth worst in the U.S., but it helps with the funding," Christoffels said.
If more of that funding is made available in the near future, construction could start as soon as 2021. If not, drivers will start seeing a change starting in the year 2023. It's expected to take about two to three years to complete.
Eyewitness News is taking a close look at traffic in Southern California, focusing on possible solutions and what's being done to improve it. Watch for our coverage all week long.
All Southern California Traffic coverage here: https://abc7.la/2qBa5uR
Traffic in Southern California: What's being done to fix California's worst traffic bottleneck