Barton Road in Eccles is to remain closed until the end of May, Salford council have admitted.
The link route between the town and the Trafford Centre has been shut to general traffic since 8 February.
The road was closed from the A57 Liverpool Road, at Patricroft bridge, so council workers could install new crash barriers, new kerbs, street lighting and widen the footpath along the Bridgewater Canal.
Work was supposed to be finished by the end of March.
But Salford council say utility companies are to blame for failing to come out in time to divert cables, delaying the work.
They today apologised for the delay.
Barton Road will now be closed to the junction with Barton Lane until at least Friday 27 May.
Diversions will continue down Peel Green Road.
Salford City Council is spending £3.6 million of Heritage Lottery Funding to improve the Bridgewater Canal, including renovating footpaths and cycleways.
Ben Dolan, Strategic Director Salford City Council said: “Work on the footpath and roadway is progressing but unfortunately there have been delays in utilities companies coming out to divert cables and in replacing the crash barrier.
“The crash barrier would prevent a car going into the canal in the event of an accident. It is an essential piece of safety equipment and has to be in place before the road can fully re-open.”