A mikvah (Hebrew for a "gathering" [of water]), is a ritual pool or bath of clear water, that is part of a Jewish tradition relating to the concept of taharah (ritual purity) and tumah (ritual impurity). After immersion in a mikvah, a person becomes ritually clean. There are a number of ways to be considered "ritually unclean" - through contact with the dead, certain illnesses, and by childbirth or menstruation. A separate mikvah is also used to immerse "vessels" (utensils, pots and pans and dishes). Today the most common use of the mikvah is for women, prior to marriage, and following the birth of a child. Immersion in a mikvah is also obligatory for converts to Judaism. Some men also practice immersion in a mikvah on the eve of the Sabbath and festivals, especially on Yom Kippur (the Day of Atonement). At the beginning of the 21st century, mikvah immersion, in some streams of Judaism has become a ritual to mark a new beginning or to mark a change in life for both women and men. Miscarriage, infertility, and illness or healing from divorce are examples of new ways in which mikvah are used by some less Orthodox branches of Judaism.

A mikvah is considered to be one of the most important Jewish institutions in any traditional Jewish community. According to Jewish law, before a Jewish community erects a synagogue or school, a Mikvah should be built. This is a considerable undertaking, because whereas a school or synagogue has greater latitude of design with only a few essential elements for a synagogue (and none for a school), a mikvah is built to very stringent specifications relating to biblical and Talmudic dictates. It must be composed of stationary, not flowing, waters and must contain a certain percentage of water derived from natural sources, including a lake, an ocean, or, in the case of the Buffalo Ritualarium, rain. Size and design also have specifications that must be followed for the mikvah to be acceptable under Jewish law.

The Mikvah at 1019 Maple Road in Amherst, NY, also known as the Buffalo Ritualarium and the Klein-Deutch Mikvah opened in 2000. Fundraising and its building began in 1998. Another Mikvah preceded it and was also called the Buffalo Ritualarium, however, in popular parlance, it was known as the "Kenmore Mikvah". It first opened on August 4, 1957. The founding and sustaining group for the Kenmore Mikvah were honored at the tenth anniversary of the new mikvah on Maple Road in 2010. Rabbi Justin Hofmann, B'nai B'rith Hillel Director of Buffalo for 29 years, helped build and sustain the Kenmore Mikvah for two decades, and Miriam Stern acted as director, secretary, attendant and custodian for over twenty years, carrying out the day to day activities needed to maintain the mikvah between uses. Other mikvaot existed in Buffalo before 1957, as referenced in very early Beth El synagogue minutes, but no records of these have been located.