The Dimmer Approach to Water Conservation

In a short article written for the San Jose Mercury News online, Ron Duncan from the Soquel Creek Water District describes a novel approach to saving water that can yield water savings of 10%. To effortlessly achieve these savings, Duncan encourages consumers to apply "the dimmer switch" approach, a reference to reducing energy use by dimming the lights. While I can't vouch for the effectiveness of this approach, it certainly seems logical enough.

In a nutshell, the dimmer switch approach is a water conservation strategy that utilizes the fact that most of our water fixtures--bathroom and kitchen faucets, shower heads and outdoor water spigots--allow us to adjust the flow of water coming out. Duncan has observed that for most uses, people will turn a fixture on to full blast regardless of whether or not a powerful stream of water is actually needed for the task at hand:

Daily observations and reported data show that when showering, brushing our teeth, washing our hands or dishes, we turn the water on full blast, 100 percent, as if it's all or nothing. Check it out next time you run a faucet or shower. Maybe you have even heard the banging of your pipes when the high water flow is abruptly turned off, thereby slamming water against the pipes.

For the past few months, I have been trying to see how far one can reduce the flow of water and still have comfortable and sufficient amounts for the task at hand. Achieving significant success in the kitchen and bathroom is relatively easy. I quickly learned that really only about half the normal full flow is needed for washing items i.e., hands, dishes, food items.

When was the last time you squeezed a heaping line of toothpaste onto your toothbrush only to have it run down the drain because the water pressure from sink knocked the carelessly administered pile of paste off the brush? For me it was last week, or maybe even last night. I can't really remember because its such a frequent occurrence.

Duncan also tried the dimmer approach in his shower, estimating a savings of around 20% by simply reducing the flow when he showers (I can't help but wonder what the flow rate of his shower is...):

After feeling confident from my faucet experiment, I decided to tackle the Holy Grail of water consumption -- showering. Who doesn't love a shower? The warm water softly eases away daily stresses and cleanses our bodies. Reducing the shower flow seemed slightly depriving at first. However, surprisingly quickly, after a little dialing of the shower handle, the perfect spot was found.

The shower spray now feels more natural and comfortable against my skin. The old full force spray feels harsh. The reduced flow is about 20 percent less than full blast and can save a significant amount of water and energy, too heating water requires a lot of energy. All these savings and a more comfortable shower combine for a great solution.