Nishmat's Women’s Health and HalachaIn memory of Chaya Mirel bat R' Avraham

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Lake formed by dam in river

29 November, 2021


Hello, the page discussing immersion in rivers answers most, but not all of my questions. On the page, it reads, “a natural lake that is fed by river water and springs may be used for the immersion.” The remaining question is: If a lake is formed on a river by way of building a dam in the river, is this newly formed collection of water still considered kosher for the mikveh? The river water still flows over the dam and downstream into the original river channel. There are easy beach-style entries into this body of water for easy privacy concerns.


Since the river flows through the lake and over the dam, the lake that you describe should be considered a kosher mikveh, as long as the river is mostly fed by springs or other rivers (and not rainwater).

However, it’s not always easy to determine the source of the water, especially in winter and early summer, so if you are unsure it would be wise to investigate further.

Please let us know if we can be of further assistance.

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