A leaky manhole which was causing ice to form on Southover High Street in Lewes will be fixed, said Southern Water.
It has carried out a temporary repair to the water main and plans to return soon to mend it permanently.
Cllr Ruth O’Keeffe raised concerns about the problem, pointing out the ice on the road could lead to a serious accident.
There was also a dispute between East Sussex County Council and Southern Water as to whose responsibility the leak was to fix.
But a Southern Water spokesman said: “Our continued investigations into the water in Southover High Street have revealed that a leaky air valve on one of our water mains may be to blame.
“Previous inspections missed this piece of equipment as the manhole cover had been replaced with a generic one which did not identify it as Southern Water’s.
“We have made a temporary repair, which appears to have stopped the water, and will return soon to make a permanent repair once we have agreement from Highways.
“We apologise for the confusion and delay in resolving this issue.”
Cllr Ruth O’Keeffe said people living right next to the road were concerned a lorry could have hit their homes as a result of ice forming next to The Swan pub in Lewes.
She was worried that as the temperatures plummeted both pedestrians and drivers could be put at risk by the black ice which resulted.
Cllr O’Keeffe added she thought a lorry might hit houses on the road.
The water leak had been a problem for about a year.
Cllr Ruth O’Keeffe, who has been working with residents to resolve the issue, said: “I am very glad to hear that the cause of the leak may have been identified, as this takes us a lot further towards it being sorted out. However I think cautious optimism is the order of the day for now, as the present repair is only a temporary one. I look forward to hearing that the repair has been made permanent”. She added there had been problems with a leak for well over a year.