Hahahahaha...
But no. Bacteria do not necessarily dwell in the water. Water is not the only substance that provides a ideal condition for bacteria to survive. Bacteria can exist in the water moisture. (in air, that is)
Therefore, when we flush the toilet or when we hose the garden, we are exposed to the water moisture where the bacteria can exist. Don't tell me we are careful enough to avoid single H2O particle in the air. Only place where bacterica cannot survive are the sealed places with either extremely low or high temperature that are not exposed to the external environment. (air-tight)