Aura Leisure Centre in Letterkenny was evacuated last night due to a flooding incident.
Emergency services responded to the scene at around 8.30pm with the facility evacuated around an hour before it was due to close.
There are reports of significant structural damage with the internal roof of the reception area particularly affected.
The incident comes as the 2020 World Tug of War Championships get underway there today - the event is going ahead as planned from 9.30am this morning.
The side of the venue where the championships are taking place has not been affected.