ludern, lock covered in mud?

[T21]

I read that you have to press a lever twice for it to flood but I can't find that lever either outside or inside the basement, I appreciate your help.

[Usikava]

You mix up tomb thing with lever and crime and chaos path quest, you won't be able to open it up until you have a crime and chaos path in high levels (like 8 or 10 can't recall correctly)...