LAWRENCE — A water contractor working for the city on routine checks of water valves in preparation for paving "inadvertently closed a gas valve, puncturing an active gas main," according to a statement issued Friday night by Mayor Dan Rivera, the state Department of Public Utilities, and Columbia Gas.

The statement, put out about 6:30 p.m., goes on to say that the gas valve "should have been disabled as part of pipeline reconstruction in 2018 and was not compliant with DPU standards."

"Columbia Gas has identified 45 gas valves that the DPU has required Columbia Gas and mutual-aid partners to immediately inspect and bring into compliance if necessary," the statement says. "The process of inspecting and remediating these valves, located near the surface level of the road, will not require excavating and will be completed by Saturday.

"Until then, the DPU has instructed all municipalities in the Merrimack Valley to suspend all construction and maintenance projects in the affected area until the valves are determined to be safe.

"The DPU will continue to closely monitor the restoration effort and Columbia Gas will be required to continue to use mobile leak detection equipment in the form of 'sniffer trucks.'

"The small number of residents who have not yet returned home should expect to return home following completion of testing of the impacted pipeline to ensure safe operation. The DPU's investigation into the incident is ongoing."

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