Friday, April 18, 2008

Water, Water, Everywhere

A couple days ago on Morning Edition, I heard yet another story about how tap water is now dangerous. This time the story was about Congress starting a series of hearings on the findings that tap water in various cities was found to have minuscule amounts of multiple prescription drugs, and included a scientist who said that although tests had determined that people were not affected by such minute amounts of individual drugs, it was not clear what the results could be from ingesting the combination of all of them.

Now I'm normally concerned about pollution, and the idea that our water is laced with random medications is kind of scary. But the more I hear about it, the more I get frustrated. First of all, the proportions of chemicals they're finding are tiny - so much so that we are only able to trace them now with the latest equipment; just a few years ago we wouldn't have even known we had this problem. That doesn't make them safe, but it does mean we're in a media-induced frenzy over something that likely has been going on for a long time.

Second, water is one of the few truly recyclable resources, as many drought-ridden cities are starting to realize. Cleaning and filtering sewer water, while it definitely has the "yuck" factor, is much cheaper, takes less energy, and has fewer bad byproducts than de-salination, which somehow seems so much less gross. Desalination is extremely energy-intensive, which is why it's generally done only in oil-rich, water-pour Middle-Eastern countries. Furthermore, Ocean water isn't actually all that clean - there's a whole lot of raw sewage (thank you, Victoria and Mr. Floatie, among other places!), garbage, and salt. And after they de-salinate and remove that briny, gross stuff, what do plants generally do? Throw it back in the ocean, of course, so the problem just gets worse. Cities like San Diego are finally figuring this out and building sewage to tap plants despite public concern.

Clearly we're not going to get away from this problem. There's less "clean" (i.e. evaporated, rained down, and filtered through some rock into a stream or lake) water available and more people who want to drink it. We can do better at conserving by reusing our grey water for gardening and other non-potable needs, but ultimately we need to drink. The only alternative I can think of is for all of us to start drinking mead. Either the alcohol will kill off anything bad in the water, or if it can't, at least we'll all be happier.

1 comment:

Anonymous said...

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When evaluating a desalination project Reverse Osmosis is typically the process considered. Yet, there is a viable and proven alternative in distillation with lower costs.

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The system produces outputs of either valuable crystalline salt or concentrated brine. The
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