I was washing my hands the other day and thought, how much water do we waste when we just flick/turn on the tap without any regard to the actual water flow? Yes, I know, I have weird thoughts, but hear me out.
Most newer houses now have flick mixers for most taps instead of the standard hot and cold knobs. But the downside of them is that unless you deliberately try, they're very difficult to flick on without either too much water flowing out, or too little water flowing out. So when we're in a rush or lazy, we usually just flick it so more than enough water is needed. (Normal hot and cold knobs are less prone, but people can still be lazy and just give it a half turn regardless of the water flow.)
Fixing our laziness or rush is clearly not possible, so why not fix the tap itself?
What if there is a notch in the flick mixer such that a light tap will make the flick mixer open up to that notch, giving just enough water flow for washing hands, rinsing etc.? And if you need a higher water flow, e.g. filling the sink, just push the lever further back as you do now.
I'm sure this isn't a new idea given that only a small mechanical change is needed, and I'm not exactly up with the latest in tap technology so there's probably a tap like this already. It won't fix the water crisis here overnight, but every little bit helps, right?
Oh - no that Dorf mixer I put there doesn't have this feature; I just wanted a picture of a flick mixer and couldn't find a CC one on flickr.
P.S. This has to be the weirdest post I've written to date here; yes, exams really are driving me mental, my mind's trying to think of anything but exams 
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