I wrote a couple of days ago about a simple system for monitoring the strength of one’s tea, whilst your teabag is brewing in the cup.
Well, it’s time for a return to the exciting arena that is plumbing, by applying a similar approach to the flush toilet.
Imagine a light emitter and receiver pair located on either side of the toilet bowl (underwater). It can arranged that when the toilet is flushed, water only flows until its local optical transmissability returns to a preset level. This means that the flushing terminates a few seconds after the toilet has cleared itself and the remaining water is clean. In this way, massive amounts of water can be saved which would otherwise be wasted.
This would allow the use of a cistern taking the form of a tall, thin, flat-to the wall tank (more like a domestic radiator). If the bowl is sensed not to be not clearing effectively, a valve could be opened wider than normal to allow an inrush of water at much higher than normal pressure (due to the height of the tank).
This would allow the flushing to be adaptive to requirements and lessen the frequency of blockages. It would require a level sensor (or a flowmeter) to ensure that the amount of water supplied was never enough to overflow the toilet.