Repairs to a leaking gas pipe mean one lane of the A23 at the Ifield Avenue roundabout, Crawley, will be closed for a week.
The repair work is being carried out by Southern Gas Networks and is scheduled to end on June 18.
One driver, whose usual 20-minute journey took an hour this morning (June 11), complained no warning about the lane closure had been given.
She said she was diverted through Stagelands, Langley Green, and added: “The road is not big enough for diversions what with the buses going down there and the cars parked.
“If I’d known they were closing the road, I certainly wouldn’t have come in that way.”
For further information, contact Southern Gas Networks on 0845 070 1431.