The M6 motorway has been closed in both directions since lunchtime, after a truck overturned and shed its load across the carriageways.
The accident happened between the Ballinasloe and Athlone exit and it is understood nobody sustained injuries.
Gardaí are advising motorists travelling from Galway towards Athlone to come off the M6 at junction 14 – the Ballinsloe exit and take the old road to Athlone.
Motorists travelling from Dublin towards Galway are advised to exit the motorway in Athlone and take the old road to Ballinasloe, where they can resume their journey on the M6.
Emergency services are still on the scene and Gardaí say they hope to have the road open tonight.