Spoilt for choice about what to blog about this month. I have been showering in North Wales, Devon, Belgium, Germany and France. I had my first (and only, I hope) cold shower, and measured flow rates in the shower at the Marriot Hotel in Ghent. (Just thought I’d drop that in!) Most of the showers were in soft water areas, a nice change from showering in London where the water is very hard, and I will certainly blog about that at some point soon. But as I have just spent a week in Devon where water costs over 2.5 times as much as it does on London and as I am unlikely to be down that way again anytime soon, it seemed apposite to work out whether the cost of showering in Devon would preclude a move there.

Water in Devon is provided by South West Water and currently costs £5.26/m3 (the most expensive in the UK) as compared to £1.88/m3 in London where the water is supplied by Thames Water1. There are historical reasons for this difference. In 1990 (when the water industry was privatised) 40% of the sewage in Devon and Cornwall was discharged directly into the sea with no treatment at all. In 2000, the EU’s Urban Wastewater Treatment Directive banned this practice, and South West Water’s customers have been covering the cost of bringing the sewage system up to the required standard ever since. Thames Water’s customers benefit from the fact that London is part of their catchment area, with a lot of buildings in a relatively small space, hence a greater number of paying customers per linear mile of supply pipework and sewers.

The calculations below assume that I am paying for water based on actual volume used (which currently only applies to 40% of dwellings in the UK) as opposed to rateable value, and I have not added any standing charges into the calculations. Both our house, and the place we were staying at in Devon, are on a water meter.

As already mentioned in previous blogs the flow rate from our shower is 7.5 litres/minute, I have the shower on for about 2.5 minutes and it takes 45 seconds for the hot water to arrive from the combi boiler, resulting in 25 litres approx for each shower. Assuming one shower a day I use 9,125 litres (9.125m3) of water a year to shower, costing £17.16.

The flow rate in the cottage in Devon was 5.7 litres/minute, and it took less than 30 seconds for the water to arrive from the hot water cylinder, resulting in 17 litres per shower. Assuming one shower a day I would use 6,205 litres (6.205m3) of water a year to shower, almost one third less water. However, it would cost me £32.63.

Not surprisingly, an extra £15.47 for showering would be unlikely to dissuade me from moving to Devon, and the relatively small amounts of money involved in both scenarios is because of my efficient (some would say frugal) showering technique. But it is worth considering that a family of four (using the UK average of 150 litres of water a day per person) would pay £1,151.94 a year for their water use in Devon compared to just £411.72 if they lived in London.


  1. Water prices are increased every April 1st, have to be agreed by Ofwat, and almost always rise by more than the rate of inflation.
photo credit: Kaptain Kobold <a href=”http://www.flickr.com/photos/95492938@N00/3413829850″>Cream Tea</a> via <a href=”http://photopin.com”>photopin</a> <a href=”https://creativecommons.org/licenses/by-nc-sa/2.0/”>(license)</a>
August 2012 – Save money – Shower in London