The MBTA announced Sunday night that the green and orange lines had fully reopened after partially closing around Haymarket station at the end of last week.
The transit authority had announced on Thursday evening that a contractor had discovered that the support columns of a private garage in the Government Center running through the MBTA tunnels near Haymarket station had deteriorated.
Orange Line service between Back Bay and North Station was suspended, and the Green Line was with shuttles between Lechmere and Government Center stations.
The contractor told the MBTA that the columns were in such disrepair that the tunnels were unsafe for trains to pass through.
The transport authority expected the closure to last several days.
On Sunday, the MBTA tweeted that it had worked with the contractor, HYM Construction, to reinforce the support columns.
“Engineering and safety experts have reviewed the repair work and have determined that it is structurally sound and therefore safe to resume service on the Orange and Green Lines,” he wrote.
The MBTA also tweeted that the orange and green lines have been operating normally since Sunday evening.
“We can’t thank our riders enough for their patience during this work, and are grateful to our workers who went above and beyond to support this effort,” he wrote on Twitter.
On Thursday, the MBTA and HYM Construction clashed over support liability after MBTA chief executive Steve Poftak blamed HYM Construction for the shutdown in a statement.
The MBTA explained that the racks were part of a private garage, even though they passed through MBTA tunnels. Therefore, it was the responsibility of the contractor working for the private garage to maintain them.
But HYM Construction hit back in a statement to WBZ-TV, saying the support columns had deteriorated due to water damage and the condition of the columns had nothing to do with HYM’s demolition work. Construction on the garage.
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