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Water woes

Green and confused: How can I convince my family to save water? - Times Online
Living in a rural area, we don’t have our water metered but I’m always telling my menfolk not to leave taps on. They say there’s plenty of rain and I shouldn’t badger them. Do you have some ammuntioon (sic) to convince them?

....we waste water — flushing needlessly large amounts down the toilet, leaving taps running, literally throwing it away. We should all visit a village in northern India or Central Asia where people have to walk miles for just one container of precious water. Climate modellers predict that the high temperatures experienced in the summer of 2003 could be the norm by 2040. Rainfall patterns will alter: while little change is likely in the North of Scotland, the South of England could experience a 40 per cent decline in summer precipitation, meaning aquifers would dry up, rivers become a trickle and crops and gardens wither. The average consumption of water a person in the UK is 150 litres a day. But add in the “virtual water” content used to produce and transport food, clothing, computer chips and other items in the UK and that figure comes to a 4,600 litres a person a day.
We live in an interdependent world in which water resources are under severe strain. So tell your family to keep quiet — and shut off that tap.

I hadn't realised I was wasting all that water. We are going to run out in 2040 and then I will wish I hadn't poured it all away for it never to be seen again. Where is it all going? How can we get it back to recycle it? If only millions of us had descended on the thirsty and drank their water we would have known better.

Comments

Englishman quotes (though I think not necessarily supportively): "But add in the “virtual water” content used to produce and transport food, clothing, computer chips and other items in the UK and that figure comes to a 4,600 litres a person a day."

Well, I thought I'd work out what that was, in terms of centimetres of precipitation (rainfall etc) per year, and compare it to the actual rainfall etc. I could not find an average figure for UK precipitation in my quick search. However, I did translate the 4,600 litres per person per day into average precipitation per year.

As there is always a risk that I've made a mistake in the basic figures or arithmetic, here is what I did. 4,600 litres/day times population (61.6 million from Wikipedia) time days in year (365) divided by UK land area (244,820 square km) divided by number of litres in a cubic metre (1,000). This gives an average depth over the country of this 'virtual water' used per year of 42.246 cm.

Now, IIRC, something like 4% of UK precipitation is processed into the piped water supply; also IIRC, UK rainfall etc varies between around 20cm and 125cm.

I certainly cannot reconcile this 42cm being 4% of rainfall etc, because that would mean an average annual rainfall of 10.5 metres.

The simplest explanation I can come up with is that the 4,600 litres per person per day is the UK total rainfall, or some very large proportion of it. I suppose this might fit with producing food. I suppose it might also fit with an allocation of all that foreign water used to produce food and other goods that we consume in the UK, though I would want to know that there has been a fair deduction for the water usage 'embodied' in UK exports.

Can anyone throw more light on this figure of 4,600 litres per person per day?

Best regards

Well, after a bit under 12 hours, I've noticed that I have not recalled everything correctly in my earlier comment. Would anyone else like a go at what was wrong, and even hazard a guess as to the cause of my mistake?

Best regards

"We should all visit a village in northern India or Central Asia where people have to walk miles for just one container of precious water."

This is just stupid. Saving or "wasting" water here has no effect whatsoever on villages in northern India or Central Asia. My water comes from one of the biggest reservoirs in Europe (Kielder, Northumberland), and there's so much of it it's not metered. We could all wash our cars every day and have no discernible effect on the supply. The populations of the drought zones of the world are being given a simple message. There's not enough water there given the current conditions, and you have three basic alternatives: change the way you use water, drag yourself into the 18th century, or move somewhere else.

"..This is just stupid. Saving or "wasting" water here has no effect whatsoever on villages in northern India or Central Asia. My water comes from one of the biggest reservoirs in Europe (Kielder, Northumberland), and there's so much of it it's not metered. We could all wash our cars every day and have no discernible effect on the supply.."

It's a lot worse than you think.

Water operates in a cycle. There can never be a shortage of water per se - more will always come back at you. What there can easily be, however, is a shortage of WATER SUPPLY.

This occurs when we do not make adequate provision for storage and distribution of the boundless water that surrounds us. The proble is that it costs money to make reservoirs and pipework - money that the water companies would rather see providing profits for themselves. So they are ecstatic when people call for water conservation - this means they do not need to increase investment and can just keep creaming off profit.

If we want more water and a reliable supply, the critical requirement is for us to USE MORE WATER. Then the companies will be forced to provide more supply. If we use less water, we will be given a meagre supply infrastructure, which will fail during minor droughts. Why is this so hard to understand that nobody ever mentions it?

And the same applies to electricity as well....

And of course, Dodgy, The water companies having to pay stupid amounts of money to purify water to absurd EU mandated levels of purity, leaving less money for infrastructure improvement and maintenance, has nothing to do with this...

These plebs don't seem to understand that water is a basic human need. When you are living on a salary of £40,000 per year, to be £80,000+ by 2040, you will not allow yourself to run out of water.

So no takers yet for the correction. Factual errors are a real problem, so I must now publish the necessary correction.

I actually gave the wrong UK rainfall: it ranges from around 60cm (South East and East Anglia) to around 458cm per annum (mountainous bits, especially in the west). My mistake was a recollection in inches (also a bit approximate) and belief that it was centimetres.

This of course means that the 4,600 litres per year per head of population cannot be average rainfall. That does not stop the 'virtual water' concept being extremely dubious, both as a measure of anything and as a contributor to rational and evidence-based policy decision.

Best regards

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