Also had a leak in the server room once.
Now, the servers' located in the basement. Which is Not A Good Idea.
However, the buidling is on a hillside, which allows the western part of the basement to be open. So flooding will not be a problem.
Seems that the builders neglected to check on the horizontal level of the floor (which is now the server room). I've found out only after the fact that it is NOT truly horizontal, but tend to incline towards the western side, which has a wall. The door is to the east, where you enter and exit.
It should be pretty waterproof, but we had to cut a hole in the wall for a fiber-optic (dang word, I never know if it's fibre or fiber, but anyway) conduit. It was sealed properly and everything.
For the first year things went well. Second year, the conduit piping carrying the fiber inside started to crack due to vehicular traffic. Third year we had a nice water leak outside the premises... and yup, water entered the server room.
Luckily the critical servers was high enough to keep their toesies dry. And I'm glad I did not get electrocuted - I waded into that mess barefoot. Water got warmer at a point, then I noticed that a kettle plug had immersed itself in the water - and I skedaddled out of there at a good pace, and refused to enter again until all the water had been pumped out.
It woke manglement up, and the company had to spend some $$$ in getting proper drainage installed to keep water away from the server room.
So far we've had a couple of rainstorms etc, but the server room remained properly dry.
Only time will tell if we'll have a repeat performance or not. If it does happen again, the servers will be relocated somewhere else... which'll be a major PITA.
And for the record, I will not try this experiment again, with a live electrical connection submerged...