ENGINEERS/PLUMBERS: THINKING HATS ON: What OTHER WAYS are there to CONTROL WATER LEVEL and WHY?

Okay, I need real, answers, if you can't think of a real answer just please star the question.





I need a way to control the level of water going into a system.





An example would be a toilet system, if you have ever noticed and opened up the lid of a toilet, to see how the flush mechanism works then it is a baloon with a lever system which controls the flow of water and therefore controls the level of water also.





So APART from the toilet can you think of





(a) any other system which controls the water level ? (e.g. toilet)





(b) the method of HOW it controls the water level ? (e.g. baloon and lever)





Btw - it has to be something which I can do PRACTICALLY and CHEAPLY.





ALL i have to do is get a PRACTICAL way of doing thisENGINEERS/PLUMBERS: THINKING HATS ON: What OTHER WAYS are there to CONTROL WATER LEVEL and WHY?
Sluices, Dams, Floodgates, Lock Gates, Stopcocks...... and they're BALLCOCKS not baloons wrongly spelt...... and how many times do you need to ask it - not once in the correct section....


I suppose it's part of your coursework so now we're doing your homework too are we....