tap water on Pesach

Question

The New Croton Reservoir supplies much of New York City's tap water, and people are allowed to — and do — go out on boats and fish. I'd venture a guess that almost every Saturday and Sunday, a piece of bread falls into the water.

I don't know how long it takes for the water to reach New York, but strongly suspect that the water at the tap in New York is connected by water to the reservoir. (This last suspicion is amplified by the fact that the water travels to New York under gravity alone. For it to do so implies that there's no "break" in the water: any break would be filled by the water propelled by gravity.)

Even a small amount of chametz that gets mixed into water on Pesach makes the water chametz.

I know some New Yorkers do not drink (or cook with) water that comes from the tap on Pesach, but most are not so stringent. Why aren't they? What heter is there to use the water? (Sources, please, if possible.)

Answer 1

Hacham Ovadia Yosef discusses this issue in Yabia Omer Helek 7 Siman 44 in terms of the kinneret, which supplies water for most of israel. Kibbutzim along the coast are KNOWN for dumping hametz into the water. He answers that hametz dumped before pesach is nullified in 60. During pesach, he applies the concept of "tzonen bitzonen". Since the hametz and water were both cold (I.e. They weren't cooked together) the flavor of the chametz doesn't spread to all the water, and as long as you're not drinking ACTUAL hametz, there's no problem with the water. He concludes by saying that it's best to use pre-filtered water, but if not, the water is not assur.

Answer 2

R' Shneur Zalman of Liadi writes (Orach Chaim 467:48):

מי שרוצה לשאוב בפסח מבארות של נכרים או מבארות של ישראל שלא נזהר בהן מחמץ כל השנה, טוב שיסנן המים בבגד נקי בכל פעם ששואב. אבל מעיקר הדין אין מחזיקין איסור מספק.

"One who wants to draw water on Pesach from wells owned by non-Jews, or by Jews but with which they weren't careful to keep chametz away all year - it is best to strain the water through a clean cloth every time he draws water. However, according to the letter of the law, [this is not necessary, because] we don't assume out of doubt that there was something prohibited there."

There is indeed a widespread practice to use new sink aerators for Pesach, or at least to cover the sink spout with cheesecloth or something similar. I believe the main reason for this is that it's likely to have absorbed chametz during the year from dishes being washed in hot water or the like; but according to this, that would also take care of any problems of chametz in the water.

Answer 3

Rabbi Shlomo Zalman Auerbach ruled that while yes, we say "chametz is not nullified even 1/1000", but a few pieces of bread in the ocean are so far past the mark that they become nullified. So somewhere between one-in-a-thousand and one-in-a-quintillion (approximate volume of the Mediterranean in gallons).

Answer 4

ialcut iosef brings the case of people throwing hames on the kineret before pesah, in practice one could say he says the same as harav auerbach, but in principle he says that hames before pesah in batel beshishim

now the question would still be pertinent if this happens during pesah itself

so if this is a hidush from harav auerbach I would say safek deoraita lehumra