It comes after a power cut in the EH46 postcode area, which meant workmen closing a lane of Queensferry Road near the junction with Drum Brae North.
Drivers have been warned to expect delays on all approaches to the city from the west.
Pictures on social media site Fife Jammer Locations shows the severity of the traffic backed up all the way to Queensferry.
Scottish Power says it aims to have power restored to the areas by midday today.
A statement on the Scottish Power website reads: “Monitoring systems on our network have alerted us to an unexpected fault affecting a number of customers over a wide area.
“We apologise for the inconvenience caused, our emergency response teams have been notified and we expect your supply to be restored by 12:00.”
Postcodes affected are EH46EH, EH46EJ, EH46EL, EH46EQ, and EH46WW.