Image via Yanko Design
Shown off on Yanko Design is a concept for a rotary dial on the end of a faucet. The idea is that we are the best judge to know how much water we need, so this is a nice water-saving middle ground between the faucets that stay on when we turn them on, or that are timed, but usually for too long. But are we really good enough at deciding just how much water we need? The water dial is based on timing - do you need 5 seconds of rinsing, or 10, or 15? You set the amount of time you'll need and the water flows for only that amount of time. This is actually really clever. Sometimes you need just a splash, and those push-button faucets run for far longer than you need. But sometimes you need plenty of water to wash your hands and those stupid faucets that you have to hold with one hand in order to wash the other can drive us nuts. So perhaps a timed amount is just right - after all, you can always dial up 5 more seconds if you need more.
However, could this be something where people dial up 15 seconds, even if they don't need that amount, because it will save them from having to mess with the faucet more than once? 15 seconds is a long time for water coming out of a faucet.
Another interesting option could be to put not only the amount of time, but the amount of water used within that amount of time. That way, people can see how much they're consuming and might be less likely to dial up more time. Of course, that depends on the water pressure of that particular faucet, but it's still a compelling option.
It seems, though, that one of the best option is one that we only see at portapotty stations at festivals and similar events -- the good old foot pump. You have both hands free to wash as quickly as possible while your foot operates the water flow. There's no fussing with turning a faucet on or off or messing with timed flow that might be too little or too much for your needs. Seems like this is the most efficient option - not to mention sanitary - and we'd love to see it make some progress in public restrooms. For now, many have the motion sensor faucets, which if calibrated correctly, also are an excellent water-saving option. Though these are still far from ubiquitous.
More on Water Faucet Solutions
Bathroom Design for Water Conservation: Water Saving Toilet, Low-flow Shower Head, Faucet Aerator
Bathroom Mirror Shows Water Consumption in LEDs As You Wash Your Face
Calculate Your Water Footprint