Triq il-Kosta between Baħar iċ-Ċagħaq and Triq Martin Luther King are closed to traffic until Friday at 5am, Transport Malta said.
It urged motorists to avoid the area.
TM said there is no access to Triq il-Kosta from Pembroke and urged drivers to use routes from Birkirkara, Mosta or Mġarr Bypass.
It said that ataffic accident this morning at Tal-Balal area created additional strain on the traffic situation on the approaches to and from the Coast Road.