The fountain and watering trough of Muhammad Bey Abu al-Dhahab were built as part of the development of larger site that also included his
mosque. The structures were built over ca. 1900/1317 AH with a three-story building. The timber ceiling dates to that construction. There are comité wooden screens on the front of the watering trough, and fine bronze grilles on the sabil that match those on the founder's mosque.
Source:
Warner, Nicholas. The monuments of historic Cairo: a map and descriptive catalogue, 100. Cairo: American University in Cairo Press, 2005.