Emergency services were called after three wheelie bins were set on fire in Grange Cohan on Friday night.
The incident happened between 3:30 and 4am.
This comes after Waterford's fire services attended 36 fires in June, according to figures presented at the most recent council meeting.
The total number of incidents is 274 so far this year, which is 99 less compared to this time last year.
Last month, there were 19 false alarm call-outs bringing the total number to 105 this year.
Garda Iain O'Byrne told WLR that Gardaí are appealing for anyone who noticed suspicious activity in Grange Cohan in the early hours of Saturday morning to contact Waterford Garda Station.
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