Mike the Mad Biologist

Clean Wastewater and the Naturalist Fallacy

In a very interesting NY Times magazine article about wastewater treatment (no, really, it is worth reading), I came across this passage:

http://www.nytimes.com/2008/08/10/magazine/10wastewater-t.html?_r=1&ref=magazine&oref=slogin

And then there are those whose first, and final, reaction is “yuck.”

“Why the hell do we have to drink our own sewage?” asks Muriel Watson, a retired schoolteacher who sat on a California water-reuse task force and founded the Revolting Grandmas to fight potable reuse. She toured the Orange County plant but came away unsatisfied. “It’s not the sun and the sky and a roaring river crashing into rocks” — nature’s way of purifying water. “It’s just equipment.”

Yes, gut-based, instead of reality-based science. Unfortunately for the Revolting One, there is this thing called data (italics mine):

It’s one of the many pardoxes of indirect potable reuse that the water leaving the plant in Fountain Valley is far cleaner than the water that it mingles with. Yes, the water entering the sewage-treatment plant in Fountain Valley is 100 percent wastewater and has a T.D.S. — a measure of water purity, T.D.S. stands for total dissolved solids and refers to the amount of trace elements in the water — of 1,000 parts per million. But after microfiltration and reverse osmosis, the T.D.S. is down to 30. (Poland Spring water has a T.D.S. of between 35 and 46.) By contrast, the “raw” water in the Anaheim basins has a T.D.S. of 600.

If everything in the Fountain Valley plant is in perfect working order, its finished water will contain no detectable levels of bacteria, pharmaceuticals or agricultural and industrial chemicals. The same can be said of very few water sources in this country. But once the Fountain Valley water mingles with the county’s other sources, its purity goes downhill. Filtering it through sand and gravel removes some contaminants, but it also adds bacteria (not necessarily harmful, and local utilities will eventually knock them out them with chlorine) and possibly pharmaceuticals.

In other words, nature messes up the expensively reclaimed water.

So why is this very clean water ‘recontaminated’? Because of ninnies like Watson. I’ve always despised naturalist arguments: untreatable sepsis infections, tooth decay, and death during child birth are also ‘natural.’ What’s worse is that many times the ‘naturalist’ viewpoint is anything but natural. Water that comes out of the tap isn’t ‘natural’; in most municipalities, it’s treated and filtered.

Or we could just completely drain all the groundwater aquifers….

Comments

  1. #1 Richard Simons
    August 17, 2008

    The capital of Namibia, Windhoek, has been recycling sewage for at least 10 years. I understand that normally the drinking water is 8% recycled but it can go up to 24%. Grey water from the treatment plant is used for irrigation at a garden centre, boulevard trees and plants around the university and government buildings. A water engineer I spoke to said he would have no hesitation in drinking the water as it came out of the plant, but in fact it goes into a reservoir.

  2. #2 Bob
    August 17, 2008

    The same argument could be made about the water treatment system at a nuclear plant. Biological, mechanical, and chemical contaminants are a big deal when you are circulating a lot of water past nuclear fuel and through large turbines. Microbes and chemicals cause corrosion, entrained particles can cause mechanical damage to fuel and turbine blades, and particles and chemicals can be made radioactive by exposure to neutrons in the core. All this adds up to expensive safety, reliability, and maintenance issues so consequently a lot of time, effort, and hardware goes into maintaining extremely high water quality.

    Would I drink cleaned up ex-reactor coolant? After seeing what they do to clean it and how they measure its purity, sure, with no hesitation.

    That sort of homeopathic thinking that water maintains some memory of the poop or radioactivity it once touched is absurd, but it’s hard to convince someone otherwise especially if they have no scientific background. Nature is not always best; the fact that we drink and breathe through the same tube is evidence of that.

  3. #3 Paul Murray
    August 17, 2008

    Focus. The goal is not the ninnies – they are uneducatable. Focus on the people the ninnies are trying to reach.

    Two prongs.

    1 – real information (such as what we have here).
    2 – discredit the ninnies. Grannies are easy targets: accuse them of thinking that the electricity leaks out of the sockets if you don’t switch them off.

  4. #4 Janne
    August 18, 2008

    Seems people like her thinks the water they get “from nature” has never been drunk and excreted by any living thing before. Terry Pratchett perhaps said it best in Reaper Man:

    “People have believed for hundreds of years that newts in a well mean that the water’s fresh and drinkable, and in all that time never asked themselves whether the newts got out to go to the lavatory.”

  5. #5 Andrew
    August 18, 2008

    This is ridiculous. I’d assume that 90%+ of the US populations drinks water from water supplies located downstream of some other city, so most of us are already drinking “our own (treated) sewage”. Are they’re really people out there who aren’t aware that they live downstream from somebody else? Do people really not realize how effective wastewater treatment is? Count me as another person who’d much rather drink from the wastewater treatment plant’s discharge pipe than from a “pristine” river or lake.

  6. #6 TomJoe
    August 18, 2008

    Heh, little does Ms. Watson realize that we all, in some way/shape/form, are drinking reclaimed wastewater when we open up that faucet.

  7. #7 Dunc
    August 19, 2008

    Pedantry: it’s the naturalistic fallacy, not the naturalist fallacy. Or even the naturist fallacy… ;)

  8. #8 Lora
    August 19, 2008

    So her objection is aesthetic?

    Is there a reason they can’t add some potted plants and a pretty waterfall made out of something autoclavable to the treatment facility? No kidding, I’ve seen greywater/sewage facilities that have a bunch of reeds, frogs and stuff growing in their upstream gravel sedimentation tanks, long before they hit the particulate and RO membrane filters. There’s no reason those couldn’t be nicely landscaped.

    From an engineering standpoint, there’s isn’t any reason that all those machines can’t come in pretty colors, either. If anodized coatings are something she’s willing to pay a premium for, I don’t have a problem with it.

  9. #9 Beverly
    August 20, 2008

    Seems to me granny probably thinks its more sanitary to drink water from plastic bottles, too; and never thinks a moment about the nickel, ethylbenzene, ethylene oxide, and benzene that making plastic generates, or the off-gassing one gets to ingest when drinking bottled water, or the three gallons of water it takes to put one gallon inside plastic bottles, or what folks like Nestle to springs and the residents around springs when they own em and want to bottle the water there. Yeah, and she probably is happy to pay the cost too; bottled water costs about 500 times what tap water costs. [shows ya how bright some people are!]

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