How the Aqualim Shower Head Works

It's easy enough to use a stopwatch to time a shower, or set an alarm to go off after your allotted shower time. But devices that measure time aren't the most exact way to monitor water use, because different showerheads use different amounts of water. Depending on the water efficiency of your chosen spout, your shower might use anywhere from 1 gallon to 7 gallons (4 to 26 liters) of water per minute [source: FYP].

If your goal is to limit your water consumption, and not just your shower time, it's helpful to monitor your actual water consumption. That's what Aqualim does: It monitors volume, not time.

Aqualim is an attachment, not an actual showerhead. You screw it into the pipe your shower water flows from, and then screw your showerhead onto Aqualim. The attachment is preset to limit your shower to a certain number of liters. In the Aqualim prototype, the amount is 40 liters (11 gallons), which gets you about five minutes with a water-conserving showerhead (that amount could change if or when the device comes to market).

The unit counts volume using a hydraulic motor. As water flows through the Aqualim, it spins a motor. The motor runs a liter counter. When the counter nears 40 liters, water pressure decreases. That's the "warning mode." When the counter reaches 40, the device cuts water flow down to a dribble.

That's not the end of the story, though -- if you're still soapy, you can resume your shower by turning off the water faucets and then turning them back on. That resets the counter, and the process starts all over again.

This feature, while certainly handy, begs the question: If you can just turn the shower right back on, how does it reduce water consumption?

Chances are good that if you find yourself standing in the shower for 20 minutes, you're not thinking much about the time. You're probably thinking about how good the steaming-hot water feels. Aqualim puts a stop to that -- or at least interrupts it.

The basic idea is twofold: First, to make bathers more aware of how much water they're using, while they're using it. Presumably, someone who installs an Aqualim cares about water conservation, so simply being alerted to each 11-gallon (40-liter) increment will have an effect.

The other part is simple annoyance: Each time users want to extend their water usage, they have to stand there cold for a few seconds, turning the faucets off and on. It's kind of like having someone walk into the bathroom every five minutes and yell, "GET OUT!" You can stay in there if you want, but it's probably worthwhile to hurry up and finish showering before you get yelled at.

At the very least, you'll be willing to go out and buy yourself a more efficient showerhead so you can get a few more minutes before the yelling starts.

According to Aqualim's Australian inventor, his teenaged daughters were using three or four cycles when he first installed the unit. They eventually got their shower time down to just one or two cycles [source: Daily]. Even if Aqualim inspired a 10-minute instead of a 15-minute shower, that's a savings of anywhere from 5 to 35 gallons (19 to 130 liters) of water a day, or up to 12,775 gallons (48,000 liters) of water per year. That's enough to fill a small residential swimming pool [source: ASI].

In March 2009, Aqualim won ABC Australia's New Inventors Award, which could help the inventors get a manufacturing deal. While you wait, you could pick up the Shower Manager, which reduces water flow after a certain preset time period. Or the "It Makes Sense Shower Head," which has a pull-chain that controls water pressure so it's basically an on-demand shower system. There's also the Waitek Shower Monitor available in Australia, which attaches to a showerhead to track water temperature and shower time and starts beeping when the water's been on for 8 minutes. It keeps on beeping until you turn the water off and then resets after a few minutes. If you turn the water back on before the reset, it'll just start beeping again.

Now there's a way to take the joy out of showering.

For more information on Aqualim, showering and water conservation, look over the links on the next page.