Also, read all of Numbers 19, as the water of purification actually had spiritually cleansing properties; it was not merely for washing off blood after sacrificial rites, but for the actual purification from sins. Ashes were mixed in with the water to give it special spiritual power. The water was even used for sprinkling:
And a man that is clean shall gather up the ashes of the heifer, and lay them up without the camp in a clean place, and it shall be kept for the congregation of the children of Israel for a water of separation: it is a purification for sin.
And a clean person shall take hyssop, and dip it in the water, and sprinkle it upon the tent, and upon all the vessels, and upon the persons that were there, and upon him that touched a bone, or one slain, or one dead, or a grave.
Water being used in the blessing of houses is also to exorcize any demonic powers from the house. Obviously others have mentioned baptism, but for Baptists this is trickier because they see the water itself as having no power; "only a symbol" as they say, which denigrates the power of symbols to mere allusions (illusions???).
But as Orthodox we know and affirm that the waters of baptism provide the forgiveness of sins; that the power of forgiveness is not only in the person, but also in the water itself. However, at the same time the person must cooperate with the grace infused in the water, as God does not force Himself. That would be rape.
So baptism is our strongest connection with the Jewish purification rites, but water rituals are in every single religion, all of which are mere types of the true Orthodox rituals. They all point to the ultimate reality which the Church contains.
I'm really surprised that Orthodox presbyters never reference these purification waters in Judaism as one of the many rituals which carried over into our worship. Theophany blessings seem to be the most obvious manifestation of this, as Theophany centers on Christ's baptism.