In 2013 the City of Charlottetown offered free “low flow” shower heads to residents with shower heads rated more than 2.5 gallons per minute (gpm). Ours was exactly 2.5 gpm, so we weren’t eligible, but I took the opportunity to live up to the spirit of the program, and replaced our shower head with a 1.6 gpm model, a simple Waterpik head that I bought at Walmart for $18.

As a result of the change, if I take a 5 minute shower, the savings of 0.9 gallons per minute translates into 4.5 gallons of water saved; over the course of a year that’s 1642 gallons (6215 litres or 6.215 m³), saved.

That’s a lot of water. About 5% of our yearly household water consumption.

Oddly, though, it’s not much of a cost savings: the city bills water usage at 26.4 cents/m³ and sewer usage at 58 cents/m³, so our yearly cost savings is only $5.25; usage-based billing amounts to only 23% or so of my quarterly water bill, the remainder coming from flat-rate daily charges. So, even though we cut our consumption by 5%, we save only about 1% on our water bill over the course of the year from the switch (of course I’m not accounting for the 6215 litres of water we don’t have to heat up every year, which has its own cost saving attached to it).

But, still, saving water is good, no matter the financial pay-off.

I didn’t suffer from the decreased flow; the Waterpik unit does a good job at maximizing power even with less water. The only negative side-effect of the switch is that, because there’s less water running through the shower head, it takes the cold water all that much longer to flush out of the system when I start up the shower in the morning. It’s not that there’s any more cold water to be flushed out, but the increased time means that I’m far more inclined to start up the shower and then go and do something else.

Like shave, for example. Or empty the washer. Or fold up the towels.

And that something else often takes longer than the cold water takes to flush out, meaning that the water is needlessly running, hot, while I’m distracted otherwise.

The Evolve ShowerStart TSV is a technical solution to this very problem:

Behavioral waste occurs when bathers use their time comfortably and efficiently while waiting for hot water to reach the shower. Instead of patiently waiting for cold water to exit the shower head most people leave to do something else. Typical activities include brushing teeth, using the washroom and picking out clothes. Because bathing only begins after the tasks have been completed, countless gallons of hot water are unintentionally wasted at the start of every shower.

I came across a mention of it via Cool Tools, and sent a note to Charlottetown Water & Sewer about it to see if they’d had any experience with it. They hadn’t. So they went out and bought one, and offered to loan it to me to beta test.

I picked it up today and did just that.

It’s an easy device to install: you just unscrew the existing shower head, screw on the ShowerStart, and then screw the shower head into the ShowerStart.

It works like this: you turn on the water as you normally would, and the cold water flushes out; as soon as 95ºF water starts to flow, the water slows to a trickle, leaving me free to shave or whatever else occupies me. When I’m ready to shower, I simply pull on the pull-cord, and the hot water starts to flow.

Here’s the beta test on video:

The water slows to a trickle after 41 seconds, meaning that, at 1.6 gpm, it’s flushing out about 4.1 litres of cold water.

Assuming that it takes me 4 minutes to shave, that means that, with the ShowerStart in place, I’m saving 3 minutes and 20 seconds in hot water needlessly running, or 20 litres of water.

Over the course of the year then, ballpark, I’ll save 7300 litres of water using this device. Which is more than I saved by switching to a low-flow showerhead.

I’ll use the ShowerStart for a couple of weeks and report back on how it works in day-to-day use.

Real World Test Results