In general, a flush toilet with a built-in clog removal system is described. Additionally, a flush toilet with a one-way valve system for efficient and water conserving operation is disclosed. In one embodiment, the disclosed toilet is defined by: a bowl connected to an drain pipe; at least one one-way valve positioned pipe; and a pump in fluid communication with the pipe so that (a) initiating the pump to force the piston downward or upward causes fluid-flow in the pipe so that the one-way valve closes or opens as a result of pressure or a vacuum against debris clogging the drain.