Tag Archives: water efficiency

11 cities most likely to run out of drinking water

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BBC has a list of the 11 cities most likely to run out of drinking water. Cape Town, South Africa is not on the list, because it is out of drinking water. Here’s the list:

  1. Sao Paulo
  2. Bangalore
  3. Beijing
  4. Cairo
  5. Jakarta
  6. Moscow
  7. Istanbul
  8. Mexico City
  9. London
  10. Tokyo
  11. Miami

London and Tokyo surprised me, while some of the high-growth developing capitals didn’t surprise me but are nonetheless extremely concerning. There are plenty of cities that probably would be on the list but aren’t because they have invested massively in desalination. many of the coastal cities on this list may ultimately have to follow suit, or else convince their national governments to invest in major pipeline projects. And this is just drinking water, of course. Food has to be grown elsewhere and brought in to all the world’s cities, and industry also has water needs. Ecosystems also need water, but does anyone expect them to be anywhere other than last on this list?

residental graywater

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Here’s an interesting report on the economics of residential graywater systems. It’s a little wishy-washy (no pun intended, ha) on the numbers, but it has some links and references that could be useful. From a quick skim, it suggests that if you can achieve a savings of about $200 a year, your system will break-even over a typical service life of around 15 years. This is more likely to happen if you have a relatively high number of people in your house and if you have relatively high water rates.

I have a low-tech, essentially free graywater setup. I turn on the shower, wash my hair and face with weird chemicals, stop up the drain, and wash the rest of myself with pure, non-toxic biodegradable soap. Then, I use a bucket to collect water for houseplants and outdoor plants. I check with NOAA online to see if there has been less than an inch of rain over the past 7 days (a very rough rule of thumb for evapotranspiration around here) and to see if there is rain expected over the next day or so. If I’m diligent about this in the summer, I end up not having to get out the hose too often. Combine all this with a rain barrel or two and I would have to get the hose out even less often.

If I were to accidentally pee in the shower…well, I’ll take the 5th on that one but I’m pretty sure the plants wouldn’t mind.