Hadith 4:106
The same narrator said that the Prophet (ﷺ) had said:
"You should not pass urine in stagnant water which is not flowing then (you may need to) wash in it."
وَبِإِسْنَادِهِ قَالَ " لاَ يَبُولَنَّ أَحَدُكُمْ فِي الْمَاءِ الدَّائِمِ الَّذِي لاَ يَجْرِي، ثُمَّ يَغْتَسِلُ فِيهِ "
Original Reference: Sahih al-Bukhari 239