use pedal is more controlable , to free your hands while using water, the pedal is more workable for human . you can imagine the concept of a car pedal
advanced :
cloud it ??
typically all peopoles have a cell phone , the cell phone can be used to identify the water consumer ,
we will use hybrid source positioning mechanism to determin the exact postion of the water consumer like GPS , wifi hotspot , cell tower
When a water user enter into a spotted area like bath then :
the software calculates the exact position of the user. so we get the bath occupied . or other water source is in use now
the software communicate with the cell phone so we get the consumer identity
the software receive the amount of water consumed
all collected data stored in a database to keep records and history for each one and used to make a decesion either reward the good or punish the bad :
for example
if area spotted is a bath in hotel : the client pay a higher tariff
if area spotted is bath in public building : high consumption should pay a high tax .