Q. I became aware that the cool water being pumped out of Lake Ontario and other major cities, before it reaches the treatment stages, is also used for cooling the pumps themselves and the motors that operate them. Is that not a case of water that ‘Naase bohem melacha’ or work was done with them, that becomes disqualified for Netilas Yodaim or washing hands before eating?
A. On question 2044 regarding washing Netilas Yodaim in places like Las Vegas and some counties in California, where literally the treated water goes from the toilet to the tap, Even if not contaminated, why should it not be disqualified as water that was used for work (cleaning, washing and drinking from it etc.), we wrote:
Poskim maintain that if the water was treated and recycled directly into the tap, it would be disqualified for Netilas Yodaim (Lehoros Nossan 10: 23, Kovetz M’beis Levy 5: 6). However, it is common that the water is reclaimed into a lake, from where it will be extracted for house use.
The above Poskim opine, that since it ends in contact with the ground and is further filtered by it, and then extracted from the underground of the lake, it is considered having gone through a “hamshacha” process, as water for a mikva is transformed by having it run over the ground. This constitutes “ponim chadoshos” or new fresh water and is permitted for netilas yodaim (See Piskei Teshuvos 160: 16: n. 58). Horav Shlomo Miller’s Shlit’a opinion is similar.”
The Rov explained that in our case, since the water being pumped is constantly connected to the lake, it does not become disqualified. This is similar to someone immersing his hands for Netilas Yodaim in a mikva, in which someone has immersed or in a lake used by boats and swimmers.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller and Horav Aharon Miller Shlit’a