Is this statement correct? "Have you ever drunk some water
Your interrogative sentence is not correct. You should say : Have you ever drunk any water? I`d replace "water" with some other word, i.e. "beer" or "wine" ... because I think that everybody drinks water. Or I might be wrong !
Anyway, this is a matter of interpretation and it does not influence the real problem of grammar you asked about.
"Some" should be replaced by "any" in interrogative and negative sentences though there are some few exceptions to the rule :
e.g. Would you like some coffee? [polite offer]
Would you be so kind and give me some water? [polite request].