A water treatment system includes a waste collection arrangement and a waste disposal arrangement. The waste collection arrangement is disposed in a pond for swirling the water to form a funnel-shaped water vortex so as to collect a waste contained in the water of the pond at a base of the water vortex. The waste disposal arrangement has an outlet positioned at a base of the water vortex pattern of the water, and includes a suction pipe upwardly extended from the outlet at a position above a water level of the water in the pond, wherein the suction pipe is adapted for guiding air to suck into the outlet to create a suction effect at the outlet, such that the waste disposal arrangement is adapted for sucking the water at the base of the water vortex so as to discharge the waste out of the pond via the outlet.