The Messenger of Allah ﷺ was asked about water and the animals and predators that frequent it. He replied, "When the water reaches two qullahs, it does not carry impurity."
أخبرنا الحسين بن حريث المروزي قال حدثنا أبو أسامة عن الوليد بن كثير عن محمد بن جعفر بن الزبير
سئل رسول الله ﷺ عن الماء وما ينوبه من الدواب والسباع فقال إذا كان الماء قلتين لم يحمل الخبث
[Sahih] Narrated by Abu Dawud in "Purification," chapter "What Makes Water Impure," hadith nos. 64 and 65, from the hadith of Abu ... through him, and by Tirmidhi, hadith no. 67, and by Ibn Majah, hadith nos. 517 and 518, from the hadith of Muhammad bin Jafar through him, Usama, nos. 517 and 518. It also appears in Kubra, hadith no. 50, and Ibn Khuzayma graded it sahih, 1/49, hadith no. 92.