Came home to water on the inside of (closed ) toilet lids and some water on floor around them on both upstairs and basement toilets when no one was home. We have a toilet on second floor that was completely dry. Any thoughts ?
It sounds like there was backflow in your sewer system. Could have been caused by a lot of things.
Last year our city sent out a notice that they were going to be power washing the sewer lines on a certain day, and suggested keep toilet lids down and perhaps to put a towel over the bowl to keep any splashing contained. You could maybe give your city a call and ask if they were doing anything similar?
If it happens again, maybe ask around the neighborhood if anyone else had it too.