Emergency repair works on a cut-through route between Preston and Longridge are due to be finished during Friday afternoon.
Electricity North West put engineers on site during Thursday afternoon in Haighton Green Lane at the D’urton Lane end near Fulwood.
It resulted in gridlock across much of the eastern and northern side of Preston as drivers were forced into roadworks in Goosnargh and Red Scar.
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But the electricity firm said engineers had made good progress on repairing the underground electricity cable.
Initially an estimate of Wednesday for a re-opening had been given by Lancashire County Council on Friday (17 January) morning.
A spokesperson for Electricity North West said: “We have been repairing an underground electricity cable following a power cut but obviously because of the location it needs the road closure and traffic management for safety while the team carries out the work.
“Unfortunately the road is not wide enough to use two way traffic lights therefore a road closure was required so we could work safely and carryout repairs.
“Site engineers have confirmed the road will re-open during Friday afternoon.”
Drivers reported delays of up to two hours during Thursday afternoon and Friday morning as traffic ground to a halt through Grimsargh and Goosnargh.
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