u/694206742

Ok so I'm a writer and I have a question about underground water safety.

So like . . . Let me set a scene. A character is trying to get to the end of a tunnel. Part of the tunnel in front of him is flooded with moving water. He tries to swim through it but is unsuccessful and turns back.

I've heard that stagnant water is dangerous but I didn't know if that applies to temporarily flooded water.

Another question would be what kind of dangers could be posed by temporarily flooded water. Microbial or otherwise.