A valve assembly (20) for an aircraft water supply system. The valve assembly (20) comprises a valve member (40), an electrical motor (64), and a mechanical returning mechanism (80). When electrical power is provided, the motor (64) can be controlled to move the valve member (40) from a first position and to a second position. The mechanism (80) is operably connected to the valve member (40) and mechanically biases it towards the first position. If a power loss occurs when the valve member (40) is in the second position, the returning mechanism (80) non-electrically (e.g., mechanically) returns the valve member (40) to the first position.