Al-Imām al-Bukhārī - upon whom be mercy - narrates: Aḥmad ibn Shabīb said: My father narrated to us, from Yūnus, from Ibn Shihāb, who said: Ḥamzah ibn ‘Abdullāh narrated to me
from his father, that: During the time of the Messenger of Allāh ﷺ, dogs would urinate and come & go to the mosque therein; for this reason the Companions did not pour water over that (place).
وَقَالَ أَحْمَدُ بْنُ شَبِيبٍ حَدَّثَنَا أَبِي، عَنْ يُونُسَ، عَنِ ابْنِ شِهَابٍ، قَالَ حَدَّثَنِي حَمْزَةُ بْنُ عَبْدِ اللَّهِ، عَنْ أَبِيهِ
قَالَ كَانَتِ الْكِلاَبُ تَبُولُ وَتُقْبِلُ وَتُدْبِرُ فِي الْمَسْجِدِ فِي زَمَانِ رَسُولِ اللَّهِ صلى الله عليه وسلم فَلَمْ يَكُونُوا يَرُشُّونَ شَيْئًا مِنْ ذَلِكَ.
Reference: Sahih Al Bukhari 174