I have the same thing happen to me all the time. Not in the same type of way, but it's all the same in the end anyway I suppose.

I get randomly dropped for probation, and for another company as part of my probation. My probation officer has never seen a dirty drop from me, but another guy I dropped dirty for alcohol. Now, everytime I come in, he fails me over bullshit. In Illinois, refusing to drop, not giving a descent sample, or not giving enough are all reasons to fail.

So I went in one day and my piss was almost completely clear. I had been drinking water all day because I don't like some dude looking over my shoulder while I piss and I need to drink it in order to go. I drink nothing but water in general, so my piss is always clear accept in the morning for my first piss. He failed me and said I was diluting it. I said, "with what?" He said I was drinking water to flush my system. I asked the fucker, "If you had to piss while someone looked over your shoulder, wouldn't you have to drink a little water do you could go too?"

Long story short, he got pissed at me for talking back to him, and he always tries to fail me now. He also had my creatine level checked and it was barely over the limit. He said nothing other than taking a drink can cause it. So I went on the internet and found out that drinking nothing but water can cause it. Bastards.