Long-term lane restrictions will begin on York Street starting Friday to accommodate construction of an extension to the underground PATH system.

York Street will be reduced to a single lane in each direction from Bremner Boulevard to Lake Shore Boulevard from January 4 to April 2020.

The city says the extension, which is expected to open to the public in June 2020, will add more underground access to Union Station and will add an additional connection with the city’s waterfront.

Crews will also be replacing aging below-grade infrastructure in the area.

Construction on the project is expected to occur from 7 a.m. to 11 p.m. Monday to Friday and 7 a.m. to 5 p.m. on Saturdays. No work will be done on Sundays or Statutory holidays.

“Motorists and cyclists who would normally travel on that portion of York Street are asked to be patient and allow extra time, or to consider an alternative route such as Bay Street or Lower Simcoe Street,” the city said in a news release issued Thursday.