An unexpected danger kept Mario Gonzalez from making it home after visiting a relative in Texas this summer. 

The 74-year-old retired teacher was driving on I-37, a highway south of San Antonio. Just before 10 p.m. local time, his pickup slammed into the back of a semi-truck parked on the side of the road. The truck's lights were off, and it was dark out. Gonzalez was speeding when he left the freeway, but an investigation found that he hit the brakes before the collision. 

"They literally had stopped, parked and turned off the lights in the roadway," said Bob Hilliard, an attorney representing Gonzalez's family in a lawsuit against the trucking company. The company is denying any wrongdoing. 

"That's a hidden danger. They're an invisible brick wall until the last second." 

This isn't the first time such an accident has happened. Just two days earlier, a Greyhound bus had slammed into three semi-trucks parked along a rest area ramp in Illinois. Three people were killed. 

There were 4,000 injury accidents involving big rigs near interstate on and off ramps in 2020, a report from the Federal Motor Carrier Safety Administration found. Another 55 accidents were fatal. 

"This is a real problem," Transportation Secretary Pete Buttigieg told CBS News. "This is not just a quality of life issue for truck drivers who deserve a good, convenient, safe place to park, but also it's a safety issue for the entire system." 

Officials from the trucking industry say drivers are often forced to park in these places because there's only enough parking spots for one out of every 11 big trucks on the road, according to a report by the National Transportation Safety Board. 

Danny Schnautz, the president of Clark Freight Lines in Houston, said that a "large percent of the time" it's "impossible" for truck drivers to find a safe place to park. The lack of parking, coupled with strict drive time rules, forces truckers into unsafe situations, he said. 

"It's a daily occurrence. It may only be for a short period of time, but when your body needs to rest, you can't just throw it aside. When you've gone through two or three rest stops and truck stops, you've already pushed the time," Schnautz said. 

CBS News found big rigs parked on freeway and rest stop shoulders across the country, from Maryland to Arizona, Indiana to Texas. This parking crowds the roads into rest areas that are already full of parked trucks. Investigators for the Gonzalez family found that that was the situation in the rest area the morning after Gonzalez died: The road was jammed with trucks on both sides. 

The Texas Department of Public Safety, which includes the highway patrol, declined a request to speak to CBS News on camera. The agency did say in a statement that it is typically not illegal for a big rig to park on the side of an off ramp, provided it's on a shoulder and not blocking the active roadway. 

Money from the bipartisan infrastructure bill and other federal programs is funding the expansion of truck parking at rest stops in several states. Meanwhile, Republican Congressman Mike Bost is sponsoring legislation that would make an additional $755 million available for states to expand truck parking.

"I hope that this is a wake-up call, that we do not have to have more of those type situations before members of Congress come to realize how important this is to get past," said Bost, who represents the state of Illinois, where the Greyhound bus accident happened. 

Gonzalez's family said they want to see laws restrict big rig parking.

"Losing (Gonzalez) has left a hole in our family, a hole that nothing's going to fill," said his daughter Lori. " There are a lot of regrets that I didn't have that opportunity have some conversations that I needed to have with him. And now I never will. So I have to live with that every day." 

In:
• Car Accident
• Semi Truck

Kris Van Cleave

Kris Van Cleave is CBS News' senior transportation and national correspondent based in Phoenix.

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