Repair work is underway on Castle Street in Dalkey after part of the road collapsed yesterday afternoon.
Dun Laoghaire Rathdown County Council engineers carried out an investigation which found the sinkhole was caused by a damaged sewage pipe.
The council says it will carry out further investigation works tomorrow to come up with a repair solution.
It says the temporary road closure is in place today and possibly for longer to allow for repair works.
