Abu Jamrah said: Ibn Abbas (may Allah be pleased with them both) seated me on his couch and narrated the hadith. I said: Did Banu Abd al-Qays make such strong nabidh? He said: "When it becomes strong, mix water into it." Then he mentioned the hadith above, but did not mention adding water in it. The order to add water here applies before intoxication develops in it, since intoxication is unlawful and it does not become pure by adding water, because the Prophet (peace and blessings be upon him) said: "Every intoxicant is unlawful."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأشربة والحد فيها / 17432