30 meters is about the height of the tower of London.
It's a long way under water.
Assuming new seals washing up would be fine.
Even swimming in a pool should be.

I did once flood a 50m wr casio by timing how long I could hold my breath under water. In fairness the instructions did say the buttons on 50m watches should not be pressed underwater, but it's OK to on 100m watches.

Dave