Yesterday evening was a nightmare as well...
Crash happened about 5:30 just past the Mahon Exit heading West..
I waited for it to ease joined the traffic about 6:45pm, still no joy was 45 mins plus moved from Laya Health Care Little Island to maybe the slip off to Dublin roughly 200 metres. It started to move then once the accident was clear. 4 lanes coming from the east merging into one doesn't work when there's an accident it can't deal with the volume.
People then tried to avoid this by heading to the city and then there was a crash on the Lower Glanmire Road.
Traffic heading to the city was backed up to Laya soon after as well.