Posted by Bella Travaglini August 5, 2010 10:05 AM
“While we continue to investigate, we believe that Saturday’s incident was caused by an electrical underground failure,” said Amy Zorich of National Grid. “We have ruled out the possibility of a correlation to natural gas.”
Since the explosion at 10:45 p.m. on Saturday night that tore up a brick sidewalk on Crombie Street, damaged parked cars and broke windows in nearby condominiums, National Grid discovered two gas main leaks in the area of Essex Street and another at Washington and Harbor streets, which is part of the same gas line that feeds Essex Street.
However, Zorich last night clarified the timetable in the discovery of those leaks and said neither was related to the manhole explosion.
The first minor gas leak found at Washington and Harbor streets occurred at about the same time as the Saturday night manhole explosion on Essex Street, but was not related said Zorich. The leak was caused by a water main break that damaged the gas line, she said.
The second leak, previously identified to be at the intersection of Essex and Washington streets, occurred in front of 7-9 Crombie St., said Zorich. This leak was discovered on Monday and also not related to the weekend explosion, she said.
Neither the Salem Fire Department or the state Fire Marshall was involved in the blast investigation, said Deputy Fire Chief Brian Harrington. They would have been involved only if there was suspicion of vandalism or some other cause other than an accident or if there had been and injury or fatality, he said.
While National Grid maintains that there was one manhole explosion at around 10:45 p.m. Saturday night at Essex and Crombie streets that traveled down three other Essex Street manholes, Harrington maintains there were at least two explosions – the first, on Essex Street close to the Crombie street intersection and the second in front of 7 Crombie St.
“About 10 minutes after we arrived in response to the initial call and we were telling people to get back in their homes, there was a major explosion,” said Harrington. “Five minutes later, there were at least two small explosions that affected six manhole covers all together.”
Several manhole covers had lifted off the ground during the incident and flames shot from the manhole involved in the initial blast, said Harrington.
There were some reports from residents who said they smelled a strong odor prior to the explosion, said Zorich. She explained that when an underground electrical cable begins to fail, the electricity erodes or burns a protective covering on the cable and that burning may cause such an odor.
Harrington, who has been a Salem firefighter for 30 years, said he has never seen an incident like Saturday night’s manhole blast. No one was injured in the explosion, but had it occurred in an area such as Washington Street where there are many restaurants and bars, there may have been injuries, he said.
“It was a warm night and there were a lot of people walking on Washington Street,” said Harrington. “If that blast happened on Washington Street, we would be having a different conversation.”