Abstract: An open water pump comprises an upper casing, a lower casing, an impeller having a central shaft and a plurality of blades. Each blade has an upper portion and a lower portion. The upper casing has an upper chamber, the lower casing has a lower chamber. A plurality of inlets attached below and to a side of the lower casing, and a plurality of outlets attached to a side of the upper casing. At least the bottom portion of the lower portion of each blade which attached to the shaft gradually bends along a rotation direction of the impeller, and a ratio of a height of the lower portion of each blade to a height of the upper portion is between 1 and 5. The impeller can be allowed to draw water at a low water level, foam formed by washing liquid or food debris on the surface of water can be less likely to get into the impeller to influence the drawing of water, a sufficient amount of water can be drawn from the water inlets.