Part of the N25 in New Ross, Co Wexford, was closed this morning due to an ammonia leak at a fish factory on the quays.
Diversions were in place for several hours, and road has reopened.
An investigation into the cause of the spill, which caused no injuries, has begun.
Elsewhere, traffic disruptions are expected around the site of the Electric Picnic festival in Stradbally, Co Laois, as music fans leave the venue. Portlaoise is congested, according to AA Roadwatch.
