Ask the Rov: If a mikvah has a small leak, is it still kosher?
By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah
For a mikvah to be kosher, its water must be stationary. If water is flowing out of the mikvah — e.g., through a leak in the wall — it has the halachic status of zochalin (flowing water) and is invalid, either min hatorah or miderabanan.1
The Rashba writes that only a noticeable leak (zechila nikeres) invalidates a mikvah, for otherwise, virtually all mikvah walls absorb a small amount of water. The Shulchan Aruch rules likewise.2
What degree of leaking is considered noticeable?
Some define a noticeable leak as when there is noticeable movement in the mikvah water.3 Others hold it’s problematic even if a steady drip is seen from the outside (of an above-ground mikvah).4 Another view is that if the drop in water level is visible, it is considered a noticeable leak.5
We are always very careful to ascertain there are no leaks in the mikvah.6 Even if a crack or hole starts out small, it will grow over time and should be fixed right away. Additionally, even if the leak is permitted b’dieved, one may not rely upon a b’dieved on a regular basis.7 In practice, if a mikvah loses more than half a centimeter in a day, one should be concerned.
A mikvah can also lose water due to evaporation and heat, so when a mikvah is hot, one should not be alarmed if it loses a little bit of water.8 Thus, when inspecting a mikvah, an open bucket with water at the same level as the mikvah is placed on the steps of the mikvah. If the water level of the mikvah is lower than that of the bucket, it’s an indicator that there is a crack in addition to evaporation (which the bucket is also subject to). Many inspect the mikvah for leaks over Tisha B’av when it isn’t used.
When a crack is found, it must not be sealed with something that is mekabel tumah since it’s supporting the mikvah water and can be invalid according to some poskim. The Rebbe Rashab was particular not to use even a rubber stopper.9
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From The Weekly Farbrengen by Merkaz Anash
Discussion
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