Waste disposal units are typically used to process solid waste, such as food waste, garbage and/or other waste, into particulates small enough to pass through associated drain plumbing.  A conventional waste disposal is configured to be mounted onto a sink drain extending downward from a corresponding sink such that water/waste discharged from the sink may be directed into the disposal.  The water/waste is typically directed into a grind chamber defined above a cutting or grinding mechanism of the disposal.  The grinding mechanism is coupled to a shaft of a corresponding motor to allow the grinding mechanism to be rotated at high speeds.  The waste contained within the grind chamber is typically ground, shredded, cut and/or otherwise processed into small particulates as a result of the rotation of the grinding mechanism relative to a stationary cutter ring extending around the outer perimeter of the grinding mechanism.  The water and processed waste may then be discharged from the disposal and transmitted through the associated plumbing. 
Typically, when a waste disposal is operating, water is supplied to the disposal via the faucet of the associated sink.  Unfortunately, users often forget to turn on the water when operating the waste disposal, leading to dry operation (also referred to as dry running) of the disposal.  Such dry operation increases the likelihood of damage occurring to one or more of the disposal components, thereby potentially reducing the operational life of the waste disposal.  Moreover, even when the water is turned on during operation of a waste disposal, the amount of water received within the disposal may be insufficient to completely flush out the disposal.  As a result, a significant amount of the processed waste may remain within the disposal after it is turned off.  Such a build-up of processed waste within the disposal may often produce an undesirable odor and/or lead to performance issues. 
Accordingly, a system for supplying water to a secondary inlet of a waste disposal for cleaning the disposal and/or for preventing dry operation of the disposal would be welcomed in the technology.