BOSTON (CBS) — An East Boston man says he had been drinking before his pickup truck launched off the upper deck of Interstate 93 and crashed onto the lower deck on Sunday morning.

Vannak Sao, 33, is facing charges of operating under the influence of liquor and negligent operation of a motor vehicle. Traffic cameras caught his truck smashing through a light pole, an exit sign and several lengths of chain link fence before plummeting to the lower deck, just missing another car.

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Sao told WBZ-TV’s Nicole Jacobs that he fell asleep at the wheel before the crash at about 6:30 a.m. He said he was coming from “a buddy’s house” and admitted he had been drinking.

Vannak Sao (WBZ-TV)

Vannak Sao (WBZ-TV)

“It was a mixture of drinking and being tired,” Sao said. “I just remember kind of falling asleep and I remember hitting the snowbank and kind of rattling a little bit.”

Sao said he’s a third-shift worker who just started a new job in Chelsea and is adjusting to the sleep schedule. He has been shoveling on the side, and said it all caught up with him.

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In the aftermath of the crash, Sao said he thought he merely hit a snowbank and rolled over.

“When I woke up in the hospital, they told me I dropped like 50, 60 feet,” he said.  “I watched the video like a couple of times.”

He called the incident “irresponsible.”

“I have to accept the consequences of my actions,” he said.

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The crash left Sao with a fractured nose and swollen eye. He said he’s thankful for emergency workers and that no one else was injured.

“I think I woke up to the paramedics and firefighter and police officers pulling me out,” he said. “I might not be standing now if it wasn’t for them.”

Records show that Sao has been cited for speeding five times and has been at fault in two crashes. He said those incidents happened when he was much younger.

WBZ talked to Sao’s parents as they were leaving to visit him at Mass. General.

“I know the truck is totaled, but I’m glad he’s still alive,” Vanny Sao, the driver’s father said. “He said he probably fall asleep or something and hit the snowbank or slip and slide. I’m not sure yet.”

The barrier the truck smashed into is called an attenuator and is supposed to absorb some of the impact, but it was covered in snow and ice.

Attenuator on I-93 in Boston. (WBZ-TV)

Attenuator on I-93 in Boston. (WBZ-TV)

MassDOT says they salted the area after the accident, but would not say if they were doing anything to strengthen the barrier.

An image of the upper deck attenuator after Sunday's crash (WBZ-TV)

An image of the upper deck attenuator after Sunday’s crash (WBZ-TV)

“It’s so terrible, it’s so terrible, my mind is blanking out,” Sophia Sao, the driver’s mother said.

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The I-Team looked at a problem with a nearby stretch of highway two years ago, after a pair of crashes that sent trucks over the guardrail. MassDOT said at the time it would fix the barriers. On Monday, they said they are still working on it.