A portable sink includes a container for holding wash water, an inlet line to bring fresh water into the container, and an outlet line to remove wastewater from the container. A float valve on the inlet line maintains wash water at a selected level within the container. A faucet attached to the float valve may further provide a separate source of clean water to the user. The outlet line further includes a siphon to draw the wastewater from the container to a selected discharge location. The inlet and outlet lines may form an assembly with an inverted U shape so that the device may straddle the wall of a bucket so that no piping penetrations are made through the wall. The siphon preferably includes an airlock to prevent the ingress of air at the discharge end under conditions of less than maximum flow.