The Messenger of Allah ﷺ said, "None of you should urinate in the place where he bathes, for most whisperings of doubt come from that."Abu Abdullah Ibn Majah said, I heard Muhammad bin Yazid say, I heard Ali bin Muhammad al-Tanafisi say, "This applies only to a pit dug in the ground. As for today, it does not apply, since their bathing places are made of plaster, lime mortar, and tar. So if a person urinates and then runs water over it, there is no harm in it."
حدثنا محمد بن يحيى حدثنا عبد الرزاق أنبأنا معمر عن أشعث بن عبد الله عن الحسن
قال رسول الله ﷺ لا يبولن أحدكم في مستحمه فإن عامة الوسواس منه قال أبو عبد الله بن ماجة سمعت محمد بن يزيد يقول سمعت علي بن محمد الطنافسي يقول إنما هذا في الحفيرة فأما اليوم فلا فمغتسلاتهم الجص والصاروج والقير فإذا بال فأرسل عليه الماء لا بأس به
[Its chain of transmission is daif] Abu Dawud reported it in the Book of Purification, Chapter on urinating in the bathing place, no. 27, from the hadith of Abdul-Razzaq with this chain. Tirmidhi called it unusual (gharib), no. 21, while Hakim and Dhahabi graded it sahih. Hasan narrated with "an" (an indication of a possibly broken link), as noted before, no. 71, but the hadith of Abu Dawud, no. 28, makes it unnecessary.