Sahih al-Bukhari 239

Arabic

وَبِإِسْنَادِهِ قَالَ ‏ "‏ لاَ يَبُولَنَّ أَحَدُكُمْ فِي الْمَاءِ الدَّائِمِ الَّذِي لاَ يَجْرِي، ثُمَّ يَغْتَسِلُ فِيهِ ‏"‏‏.‏

Translation

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

Authenticity

Sahih

Reference