all my private keys was stored on the hard drive
I guess that teaches you to make backups.
Seriously though: I don't believe any of this.
I also don't believe any of it because I think that @OP just made up the story to get some good replies on his thread and nothing else. He first said that he has spilled a full glass of water on his hard drive and because of that it stopped working, and I don't think that makes any sense at all.
@OP, you should also mentioned that how you spilled the glass of water on your hard drive because most of the time the Hard Drive is fit inside a desktop or laptop, then how have to directly spilled water over it without harming those systems? Now, please don't say that you had taken that drive out of the desktop or laptop because that also doesn't make sense.
However, if you story is not made up then you should take your Hard drive to an expert, and he/she will fix it within few hours without much issue. The data of the hard drive is stored on the platters and the platters are resistant to water I guess. You don't need a recovery expert, but a hard drive technician who can repair such drives.
I still can't trust the story, but if there is any truth in your story then read my answer fully, and I'm quite sure your problem will be solved.