SAN FRANCISCO (CBS SF) — The proposed completion date for construction on San Francisco’s Central Subway extension into Chinatown has been pushed back yet again by the city’s transit officials.

Construction on the Central Subway was supposed to finally be wrapped up by the end of the month. Now officials are saying the completion date has been moved to the end of the year.

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The big headlines from Muni last week were how the agency has handled the pandemic and its suddenly fractious relationship with police amid the current wave of protests. Overshadowed was the agency’s latest update on the Central Subway now facing even greater delay.”

As one might expect, the pandemic has not helped the Central Subway get any closer to completion.

“COVID-19 also resulted in a significant decrease in efficiency of work on the Central Subway in order for the workforce to be able to maintain social distancing,” said SFMTA Director of Transportation Jeffrey Tumlin.

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A construction project that is already nearly a decade old and two years behind schedule, new issues with the Central Subway continue to emerge as the passage of time drives some new complications. 

“The most complicated of which was the new train control system. So the train control system that we bid, back before the project was initially bid, all of the technology and the requirements around that changed, mid-contract,” said Tumlin. “And then, it also needed to be integrated with the new train control system we’re planning for the existing subway.”

Tumlin told KPIX 5 construction should be finished by the end of this year, before about one year of testing and certification.

“So the current target for beginning service for passengers is the end of 2021,” he said.

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In some respects this announcement leaves the city San Franciscans where it was about a year ago. The Central Subway is a project that depends on a great many variables. For transit officials, a lot of answers they have end with, “We don’t know yet.”