Purity: Wudu in Schools of Unknown Endowment

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 267:

There is no problem in performing wuḍūʾ in the place designated for wuḍūʾ in a school or with water from a school’s pool when one does not know whether the wuḍūʾ place or pool is a charitable endowment (waqf) to the general public or only to the students of the school, as long as people usually perform wuḍūʾ in that place or with water from the pool and no one prohibits them from doing so.

-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)