We put the challenge to the team: what's the best way to save on wastewater? Here's the top 6 suggestions - which do you think is best?
1. Replace gland packing in pumps used for mining with mechanical seals. This report suggests that it would save 25 billion gallons of water per year.
Best thing: it will help in other areas too, such as decreased breakdowns and improved performance
Worst thing: it would be an uphill struggle and an expensive program to persuade every company in the world to replace their seals.
Water saved: 25 bn gallons per year
2. Go vegetarian for one day a week. Studies show that production of a burger requires 3,000 litres of water, including growing the crops to feed the cow. By contrast, a portion of vegetables uses about a quarter of that. 6.125 billion people don't go to bed hungry each day, of which 5.75 billion aren't vegetarians, so if those people went veggie for one day a week it would save about 148 trillion gallons of water per year.
Best thing: it's such a huge figure that even if you only persuaded 1% of the relevant population to do it, it would still save over 1 tn of water per year.
Worst thing: it would be difficult to pursue, as it would no doubt be resisted by meat-producing industries.
Water saved: 148 tn gallons per year
3. Charge water usage like taxes, so that the more water is used the higher the charge per litre. The average person in the UK uses 150L of water per day. Research suggests that this figure could be reduced by 1/3 using common water saving methods, so if a higher price was charged after the first 100L per person it would incentivize water saving. If these common water saving methods were employed it would save 0.7 billion gallons per year in the UK alone. In the whole world, 88 billion gallons of water is used for domestic purposes each year, so cutting that by 1/3 would be a saving of about 60 billion gallons of water per year.
Best thing: it would make money for the water companies, meaning they could actually charge less for the first 100L per person, giving lower earning people the money they need to invest in water saving.
Worst thing: it would be difficult to implement on a per person basis, as water may not be consumed from one place (eg. home and work).
Water saved: 60 bn gallons per year.
4. Wash cars using rainwater collected in water butts. There are 37 million cars in the UK, it uses approximately 38 gallons of water to wash a car, and if they're washed every fortnight using only rainwater that would save 166 billion gallons of water per year in the UK alone.
Best thing: it's free!
Worst thing: it would be unenforceable, and in any case the annual rainfall in the UK is less than 1 metre.
Water saved: 40 bn gallons per year (in the UK).
5. Everyone buy 25% less t-shirts this year than before. Over 2 billion t-shirts are sold each year, and each t-shirt uses an average of 500 gallons of water to produce. Cutting this to 1.5 billion t-shirts would save 250 billion gallons of water per year.
Best thing: there's no real hardship to buying one less t-shirt...is there?
Worst thing: again, implementation would be the biggest hurdle
Water saved: 250 bn gallons per year.
6. The quality of the water that we enjoy is highly refined and among the purest in the world, and we pour it down the drain! There are 65 million people living in the UK. We each flush a toilet 1825 times per year. Each flush uses on average 8 litres of highly purified, recycled drinking water. That equates to 954 billion litres of clean water literally thrown down the drain every year. Most water authorities will provide, free of charge, a 1 litre bag or ‘hippo’ to sit in the cistern, reducing the amount of water in the cistern by 1 litre. If everyone in the UK adopted this scheme, we as a nation would reduce the amount of waste by 119 billion litres.
Best thing: most people wouldn't even notice any difference
Worst thing: people may ignore the bags sent through, even though it was saving them money.
Water saved: 26 bn gallons per year (in the UK).