LAWRENCE, Mass. — The City of Lawrence, the Department of Public Utilities and Columbia gas confirmed that the early morning gas leak in Lawrence happened while crews were working on a water main and accidentally opened the gas line valve.
The 25 Investigates Team was the first to report the gas leak was caused by a private contractor who was hired by the City of Lawrence to repair and upgrade water mains.
In a release on Friday, officials confirmed the contractor opened the valve on what they thought was a water main, but turned out to be a high-pressure gas line, puncturing an active gas main.
When the water didn't come out, the contractor turned the valve to close the line off. In the process, that damaged a new plastic pipe that had been inserted in the gas line.
Preliminary investigation shows the gas valve should have been disabled as part of pipeline reconstruction in 2018 and was not under DPU compliances.
Out of caution, Columbia Gas has identified 45 gas valves that the DPU has required them to inspect immediately and fix, as needed.
The process of inspecting and remediating these valves will not require crews to dig into the ground and will be done by Saturday. Until then, all cities and towns in the Merrimack Valley are instructed to halt all construction and maintenance projects in the area until they are told it is safe to do so.
The DPU will continue to closely monitor the restoration effort and Columbia Gas will be required to continue using mobile leak detection equipment in the form of 'sniffer trucks.'
More than 140 residents in Lawrence woke up at around 3 a.m. on Friday to the smell of gas, just two weeks after the one-year anniversary of the Merrimack Valley gas explosions and fires.
Hundreds of residents have been forced out of their homes due to the leak and business owners were forced to close down their businesses.
Most evacuated residents were being allowed to return home safely Friday afternoon, according to Governor Baker. At a news conference shortly before 2 p.m., Baker said there was still a small group who would not be able to return home until gas service was fully restored to the area.
Baker added the Department of Public Utilities brought in other energy companies to help Columbia Gas complete the work.
Mayor Dan Rivera said Lawrence Public Schools would be open, with the exception of the Weatherbee School and Lawrence Catholic Academy. Though Lawrence High School students were eventually dismissed for the day due to a separate, unrelated incident.
Mayor Rivera said families in the area should get out of their homes and take shelter at the Arlington Street School.
Boston 25 News is trying to learn more about who the contractor was and the company's history.
The DPU continues to investigate the incident.
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