When a tanker truck carrying 8,800 gallons of gasoline exploded in flames four years ago under an overpass on the 60 Freeway, the effects of the blast were felt for days across the region's highway system.
The 60, a major truck route, was shut down in both directions between the 710 and 605 freeways. Motorists, who make more than 225,000 trips a day on the east-west artery, were forced onto Montebello streets and surrounding highways, such as the 10, 210, 605, 105 and 5 freeways.
Before all lanes reopened four days later, commute times had doubled, then tripled. Cargo shipments were delayed, and Caltrans determined that the melted steel and concrete overpass needed to be rebuilt at a cost of more than $5 million.
"Truck accidents can have a huge impact on the economy, on human beings and on traffic congestion," said Hasan Ikhrata, executive director of the Southern California Assn. of Governments, a regional planning agency. "This is something we need to pay attention to."
The association has been studying truck accidents and where they occur as part of its work developing regional transportation plans for a six-county area, including Los Angeles. By identifying hot spots, planners say they can recommend steps to reduce mishaps.
In its latest analysis of California Highway Patrol data, SCAG has identified four freeway sections in L.A. County and the Inland Empire with the highest concentrations of truck crashes per mile annually.
They are the 710 at the 60 in the East L.A. Interchange, with 7.2 accidents; the 710 between the 105 and the 91, with 5.8 accidents; the convergence of the 60 and the 57, with six crashes; and the 5 between the 710 and the 10, also in the East L.A. Interchange, with 6.6 crashes.
The figures show that the second-highest number of truck crashes can be found on three parts of the 60 between the 605 and the 710, between the 15 and the 71 — the Chino Valley Highway, formerly known as the Corona Expressway — and immediately east of the 215. The category includes the 10 between the 71 and the 215, the 605 between the 60 and the 10, and the 710 between the 91 and the Port of Long Beach as well as between the 5 and the 105.
Although human error is the leading cause of traffic accidents, officials with SCAG and the California Department of Transportation say other factors in those hot spots contribute, such as congestion, limited capacity, areas with lots of merging traffic, and the constant interface of big rigs and smaller vehicles.
With the nation's largest combined harbor, the Los Angeles area also is one of the busiest in the country, if not the world, for trucking. The 710 often handles more than 43,000 daily truck trips, the 60 up to 27,000 and the 5 about 21,500, according to Caltrans.
"This adds to the congestion and explains why there is a higher percentage of truck collisions," said Officer Edgar Figueroa, a spokesman for the CHP.
Figueroa said some truck drivers go too fast and are aggressive on the road. He added that drivers of smaller vehicles cut trucks off, often get too close or drive in their blind spots.
"Motorists need to respect trucks, give them the proper space, avoid erratic lane changes and make themselves visible," Figueroa said. "In a crash, the big rig is going to win."
He advised truckers to obey speed limits and be aware of motorists. Better trip planning to determine where truckers might encounter traffic congestion can help as well, Figueroa added.
Caltrans, the CHP and the Department of Motor Vehicles also work together on the state highway safety plan, which includes credentialing truck drivers, developing rest areas, safety inspections for trucks and ensuring that driver's licenses are current.
SCAG executive Ikhrata said one of the most effective, but more costly, ways to reduce accidents is to separate trucks from smaller vehicles by constructing truckways. He noted that truck traffic could double on many local highways in the next 20 years, further straining capacity and adding to congestion.
Caltrans and the Los Angeles County Metropolitan Transportation Authority are studying the possibility of building either elevated truck lanes on the 710 or reconfiguring the freeway with an additional lane on each side and bypasses for trucks.
Now underway is a series of fixes to the truck crash hot spot at the convergence of the 60 and 57 freeways. The perilous two-mile stretch in Diamond Bar narrows from 17 to 14 lanes while other traffic merges on and off from a local intersection.
Cars and trucks frequently veer across as many as five lanes to reach the correct exit. Officials say the area has more than 600 accidents of all types a year.
The project includes new on- and offramps to the eastbound 60, officials said. The first stage of construction, which is expected to cost about $53 million, probably will begin in the fall and be completed in spring 2017.
Though some road improvements are progressing, Ikhrata warned that there is not enough state and federal transportation money to build needed projects or even properly maintain the state's highway system.
"This is a real issue about economic opportunity and the well-being of this region," he said. "How we move goods is serious business."
To help pay for projects, Rep. Alan Lowenthal (D-Long Beach) has introduced legislation to create a national freight trust fund. If passed, shipping and transportation companies would be charged a small fee based on the weight of each load of cargo. The measure could raise an estimated $8 billion a year to improve highway safety and reduce congestion on freight corridors.
Meanwhile, Caltrans is looking into the truck crash hot spots to determine what can be done to reduce accidents, said Sheik Moinuddin, a safety and operations supervisor in the agency's Los Angeles district office.
"It is difficult to say what the specific problems are at each spot," Moinuddin said. "We have our work cut out for us to see what these numbers mean and what we can do."