How does my water use relate to climate change?

Did you know that you can cut your carbon footprint in the bathroom too?  The main source of greenhouse gas emissions in the bathroom relates to water, and especially hot water.  The more water you use, the bigger your footprint.  And we in Canada have big water footprints: we use, on average, 251 L of water per person per day in our homes (2011 data[1]).  Have you seen those big cubic containers surrounded by a metal cage at construction sites, on trucks and elsewhere?  We each use, on average, enough water to fill one of those tanks every four days in Canada for our personal needs. 

Our residential hot water heaters are often powered with natural gas, a fossil fuel that generates carbon dioxide when it burns to heat the water.  Also common are electric hot water heaters that also have a carbon footprint since roughly 10% of our electricity in Ontario is generated using fossil fuels.  If you live in an apartment building, added energy is used to bring water up to all floors.  And don’t forget the energy it takes to filter, treat, and distribute the clean water plus the energy to collect and treat the waste water.  It all adds up.

And while we can get very efficient on-demand hot water heaters, heat pump water heaters, and solar hot water systems, the easiest and cheapest way to cut our bathroom carbon footprint may be by cutting back on our water usage.  Along the way, you may see savings on your water and utility bills too.  That sounds like a win-win to me!

Here are some simple ways to cut back on water use:

1. Fix dripping taps.  A small, steady drip can add up to a lot of wasted water and associated carbon emissions.  A tap dripping every 2 seconds wastes over 10L (2.5 gal) of water per day. Taking the time to fix leaks can save money too since most leaks are simple and cheap to perform.
2. Take a shower instead of a bath. A bath takes 150 to 200 L (35-59 gal) of water, far more than a 10 minute shower with a low flow showerhead (60-80L or 15-20 gal). Saving the hot bath for a special occasion makes it that much more special and appreciated.
3. Use a low flow showerhead.  Bathing and showering accounts for an estimated 35% of our personal daily water use.  Most showerheads put out between 6 and 28 L per minute (1.5-7 gallons per minute), so choosing a low flow showerhead can have a big impact.  And low flow doesn’t have to mean standing under a pathetic drizzle, some newer showerheads can produce a very satisfying shower with very little water.
4. Make your shower zippy. Of course even an efficient showerhead doesn’t guarantee low water use because the longer you are in the shower, the more water you will use. 
5. Cut water use from the tap.  You have heard it before, turn off the water when brushing your teeth.  Adding an aerator to the tap can also help. 
6. Switch to low-flow toilets.  Older toilets use can use 13-20L (3-5 gal) or more per flush, while new low-flow toilets use as little as 3-6L (0.75-1.5 gal).  Not all low-flow toilets are created equal, however, and many of the first generation low-flow toilets were awful.  The newer generations are much better but be sure to research toilets that have good ratings for both liquid and solid wastes.

Here in the Region of Waterloo, single family homes that use more than 4.5 cubic meters of water per person per month can get a free home water consultation to check for water issues or leaks and offer suggestions for how to become more water efficient.  Taking action matters as it brings us one step closer to building a sustainable world for our children and all life to come.


[1] https://www.canada.ca/en/environment-climate-change/services/environmental-indicators/residential-water-use.html