Wednesday, February 11, 2009

Managing water

"There is no doubt that we need to rethink how we use water, especially with the human population growing rapidly, and global warming likely to produce unpredictable patterns of rainfall and drought. Nevertheless, my own research suggests that the situation may not be as dire as many are suggesting. Nations can thrive on surprisingly meagre quantities of fresh water - provided they adopt water-efficient technologies and encourage economic activity that doesn't guzzle water. I believe the looming water crisis is primarily a problem of distribution and management rather than supply. And we can solve it with existing technologies, increased investment and political will."

Certainly true: Agriculture consumes more than 80% of water resources in dry countries. The efficiency of irrigation averages at around 50%. Increasing the efficiency to 75% (very possible) will be akin to providing 50% more water.

1 comment:

Leila said...

We are hearing a lot in the eco blogging community about compost toilets and greywater - recycling bath water etc. for other uses. It seems that in places like California and Lebanon where water is so scarce, we should not be using fresh drinking water to flush our body wastes into our streams or ocean.

I know it seems improbable that a modern urban area could reconfigure its sewer systems to recycle (for instance) bath, laundry and kitchen water drains into (for instance) irrigation or natural water treatment systems. Also compost toilets, the simple ones, really need enough garden space and I don't see how they are suitable for crowded urban neighborhoods. However, they may become very necessary.

Here in Oakland, CA, we live on a lot that is 20 meters by 30 meters. From what I understand, the compost toilet proponents claim that it would be safe enough to keep a compost pile for human wastes on a property of that size, if it were managed correctly with containment and mulch.