Power Line Accident Prompts Evacuation and Subway Halt

Workers installing a gas line into a Brooklyn building accidentally struck a power line that feeds the subway on Monday, sparking electrical explosions that blew manhole covers into the air, disrupted subway service and rattled nerves in a pocket of Brooklyn Heights.

No one was hurt, but the explosions, around Joralemon Street and Willow Place, caused elevated natural gas readings and prompted the evacuation of about 180 residences and the suspension of service on two subway lines for several hours, according to officials and residents.

On Monday evening, as hazardous-materials teams ventilated buildings, residents who were kept away from their homes for more than six hours started to return.

According to John Scrivani, the deputy commissioner for operations of the city’s Office of Emergency Management, the explosions started when contractors working for the gas supplier National Grid struck a New York City Transit power line while using an underground digging tool called a missile.

“They hit the line. It caused an arc and it was an electrical explosion,” Mr. Scrivani said. Its force shattered windows in the area.

The first report of a popping manhole cover came shortly before 12:30 p.m., when the Fire Department was directed to Joralemon Street and Willow Place, according to Battalion Chief Paul Tague. “While we were here, three other covers blew,” he said. Firefighters found high carbon monoxide levels and immediately started the evacuation, he said.

The explosions crumpled parts of the cobblestone streets and set off car alarms. Kaki Burns, a 25-year old actress who was staying with a friend at 57 Joralemon Street, said she smelled gas and then heard what sounded like a bomb: “The cat jumps up. I fall down. The whole building shakes,” Ms. Burns said.

Lou Klepner, a 31-year-old Web designer, was walking on Joralemon Street when the explosions occurred. “Two of the manhole covers blew about eight feet in the air” in a jet of hot air and steam, he said. “The street shook. It smelled like a gas explosion.”

Officials evacuated buildings along Joralemon Street from Hicks Street to the Brooklyn-Queens Expressway and along the entire length of Willow Place, from Joralemon to State Streets. The No. 4 and 5 subway lines were suspended for about three hours “as a precaution,” Mr. Scrivani said.