Purity: Ruling on Tap and Shower Water Connected to a Kurr Source
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 33
With regard to water that pours out from taps and showers and flows in the pipes of bathrooms and buildings, if it is connected to a source that is equal to or greater than kurr, it is ruled to be kurr.
-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)