Need to know

Down the drain

A couple of years ago I decided to try an experiment. Luckily, given my high school science marks, it required absolutely no scientific knowledge. The experiment? To see how much water is wasted between turning the tap on and when the water is hot before washing my hands.

Most of us know the standard water facts:

  • A five-minute shower can use between 95 and 190 litres of water
  • One toilet flush uses between eight and 25 litres of water
  • Brushing one’s teeth with the tap left running uses up to eight litres of water.

It is easy to fool ourselves into believing that we are not really wasting water when rinsing vegetables under running water (they need to be cleaned), leaving the tap running while brushing our teeth (it’s just a minute or so), or in my case, waiting for the water to warm before washing my hands (I do it only once a day; most of the time I rinse under the cold water).

How differently would we feel were we to measure this water and deliberately pour it down the sink?

A family down the road at the time replaced their road-facing lawn with paving. An excellent idea, I thought, until I noticed that they hose it down regularly instead of sweeping it. How differently would they think were they to spend the same amount of time filling buckets then pouring the contents down the drain?

In effect, isn’t that exactly what we’re doing? A September 2009 report by the Water Research Commission notes that South Africa has four percent less water than previously estimated. This is a chronically stressed water country and it is estimated that by 2025 demand will outstrip supply, with water shortages occurring a full decade earlier.

The result of my experiment? I filled a 2-litre jug with water while waiting for hot water. That’s 14 litres every week, 60 litres every month and 720 litres every year, from a single activity. In my defence, I usually keep this jug of water for making coffee during the day. Even so, I admit I don’t yet know how much is wasted when rinsing vegetables, so another experiment is in order. My science teacher would be so proud.