WATCH: Manhole Explodes Near South Orange Train Station In N.J.

SOUTH ORANGE, NJ – An explosion sent a manhole cover flying into the air in South Orange on Friday, delaying traffic and setting off a social media frenzy as residents scrambled to learn what happened.

The South Orange Police Department issued a statement about the incident on Friday, alerting residents that an emergency road closure was in progress on South Orange Avenue near Sloan Street. Police advised residents and commuters to access to the train station via Church Street and the transit lot, or by parking in municipal lot #9 and walking across Sloan Street.

Police reopened eastbound traffic on South Orange Avenue around 6:37 p.m., and reopened the westbound South Orange Avenue around 8 p.m.

“Please note, PSE&G will need to return to make repairs,” police stated. “This will take place possibly Saturday, Dec. 3.”

A bystander on the scene captured a video of the manhole explosion, which can be seen below.

A bevy of local residents and commuters took to social media after the incident in a quest to learn more about the explosion and the resulting traffic.

• “My daughter called me in a panic! She's a SOMS student it scared the mess out of her and her friends. Thank god no one was hurt.”
• “Manhole covers in the middle of the street, no cars or pedestrians appear to have been in the direct area. My daughter just returned from there and was there when it happened. She said lots of fire trucks, etc. and the Friday after school crowd a bit shook up. The mom who picked them up had to detour all the way over to Montrose to get her home to us over by Marshall School. Hope all involved are okay and the PSE&G workers are safe as they investigate.”
• “It's a hot, hot mess on 3rd right now. God speed if you are trying to get around.”

WHY DO MANHOLES EXPLODE?

In March of 2015, nine separate manhole explosions rocked Montclair and Verona, stunning residents and snarling traffic in the middle of rush hour.

• See related article: Manholes Explode During Rush Hour In Montclair And Verona

Responding to questions about the Montclair and Verona explosions, PSE&G representatives provided Patch with the following statement:

“PSE&G responded with both electric and gas crews to try to determine what caused the covers to pop. Based on our investigation, there is no damage to underground electric lines, nor have we found the presence of natural gas in or near the manholes. There were no injuries and no customers are without service. The cause remains undetermined.”

• See related article: Exploding Manholes Possibly Caused By Electrical Short

The strange reality is that exploding manholes are uncomfortably commonplace in New Jersey, as well as the rest of the nation.

• Where are the explosions happening in New Jersey? See Patch’s list here

Damage from a manhole explosion can be devastating. A manhole cover can weigh between 85 and 300 pounds, and is a “significant danger to people in the vicinity” if propelled into the air after a blast, according to a Georgia Institute of Technology study. The study claimed that the energy released in the largest manhole explosions can be as powerful as 20 sticks of dynamite.

Flying manhole covers are not the only potential risk for those in the area. The fumes and smoke emanating from a manhole blast can contain PCBs or other deadly toxins, according to one report. And unvented/unignited gases such as carbon monoxide can seep their way underground into nearby buildings, creating a serious health hazard.

According to HowStuffWorks.com, most manhole explosions happen when underground electric cables – some containing up to 13,000 volts of electricity - deteriorate or get damaged due to aging, corrosion or other normal wear and tear. The damaged wires heat the surrounding insulation, which can release gases – some flammable - that build up inside the enclosed manhole. Eventually, a spark from the wires can ignite the gas and cause an explosion, sending a manhole flying up to 50 feet into the air.

Manhole explosions become much more common in the winter or summer months, according to news reports. In the winter, snow removal and plowing efforts can dump tons of road salt and melted water into the streets, some of which finds its way into the manholes. And in the summer, excessive power demands can overload feeder cables, causing short circuits.

• See related article: Manhole Explosions in New Jersey: Dangerous and Frequent

Photo: South Orange Police Department

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