In 1 Peter 3:21, Peter tells us that baptism now saves you, yet when Peter uses this phrase he continues in the same sentence to explain exactly what he means by it. He said that baptism now saves you-not the removal of dirt from the flesh (that is, not as an outward, physical act which washes dirt from the body - that is not what saves you), "but an appeal to God for a good conscience, through the resurrection of Jesus Christ" (that is, as an inward, spiritual transaction between God and the individual, a transaction that is symbolized by the outward ceremony of water baptism). By saying, "not the removal of dirt from the flesh, but an appeal to God for a good conscience, through the resurrection of Jesus Christ," Peter guards against saving power to the physical ceremony itself.
Just as the eight people in the ark were "saved THROUGH water" as they were IN THE ARK. They were not literally saved "by" the water. Hebrews 11:7 is clear on this point (..built an ARK for the SAVING of his household). NOTE: The context reveals that ONLY the righteous (Noah and his family) were DRY and therefore SAFE. In contrast, only the wicked in Noah's day came in contract with the water and they all perished.