If a mikvah is in the vicinity of shower area, what constitutes enough of a separation between these areas to permit making brachah of tevilah in the mikvah? What about בדיעבד?
Ashkenzi custom is for the woman to make the bracha in the mikvah itself. The shower poses no greater problem the the mikvah itself, which is also a place of bathing. We rely on the fact that our baths and showers are clean, don’t smell and are fit for making a bracha. Hence, the proximity of the showers is not an issue.
See Y:D 200, the Rama and commentaries there.