Traffic along Folsom Street near Fourth Street in San Francisco was already moving slowly on Friday, as ongoing construction continued to clog one of the main routes to the Bay Bridge.
That congestion is expected to worsen significantly this weekend, when a closure of eastbound Interstate 80 into San Francisco takes effect.
The shutdown, scheduled to begin late Friday night, will divert drivers onto city streets, including Folsom and nearby Bryant Street, corridors already strained by more than a year of street improvement work…