Wasting water?

Before I rant, let me just say up front I am aware that we bought a home with 3 stars in the Austin Green Building Program. Not four stars or five, but three. I get it.

Nevertheless, over the last 2.5 years I have been surprised on several occasions to discover that relatively easy and inexpensive steps to minimize our home’s energy and water needs were not taken. Consider, for example, low flow showerheads. This is serious low-hanging fruit in the water conservation arena, so naturally I assumed our 3-star home came equipped with them. You can see where this is headed.

Last weekend my son and I decided to measure the flow rate of our showerheads – I like to engage him in practical science now and again. Anyway, he manned the stopwatch while I held a 1-gallon jar under the running shower, and we took three measurements at each shower to see how fast it filled up. He did such a nice job with the timing that the average times for the two showers were .01 second apart! And the result?

Incredibly, both of our showers emit a gallon of water in less than twelve seconds! We have been using a phenomenal 5.07 gallons per minute! To put this in context, normal showerheads are supposed to emit 2.5 gallons per minute (gpm), and low-flow showerheads as low as 1.5 gpm.

Now armed with data, we can make a few calculations. I estimate that our three family members each spend an average of 46 minutes per week in the shower, so 138 minutes X 5.07 gpm X 4.33 weeks/month = 3030 gallons per month! Roughly half our monthly water use is for showers! And this is not cheap. Incoming water costs $2.62 / 1000 gal at the margin, plus $7.73 / 1000 gal for wastewater, so we’re spending over $31 per month just on shower water.

So to cut to the chase, converting both showerheads to 1.5gpm low-flow models would save just over 2100 gallons of water per month, which is about a third of our total water use. To put this in terms my son grasps, I explained that it is enough water to fill one of our smaller rainbarrels 42 times, every month!

We will also save over $22 per month on our water bill. UPS just delivered our first new showerhead, which we will test for a week before selecting a second. It cost us $60 (cheaper models are available, but the selection in oil-rubbed bronze is thin). Thus, our water-saving upgrades will pay for themselves in less than six months!

So, are you wasting water too?