Blame Cognitive Biases When Efforts To Conserve Water Aren't Effective As California's drought draws national headlines, we look at what a psychology-minded engineer has discovered when it comes to conserving water at home.

Blame Cognitive Biases When Efforts To Conserve Water Aren't Effective

Blame Cognitive Biases When Efforts To Conserve Water Aren't Effective

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As California's drought draws national headlines, we look at what a psychology-minded engineer has discovered when it comes to conserving water at home.


There's actually some new research into how people think about saving water and whether they are prepared to sacrifice. It might even offer some clues about why conservation efforts don't always work that well. NPR's social science correspondent Shankar Vedantam came in to talk about it. So what's the research here?

SHANKAR VEDANTAM, BYLINE: Well, the research comes from Shahzeen Attari at Indiana University. She's an engineer who's also interested in human behavior. Attari recently surveyed Americans and asked them, how do you think you could conserve water in your own household? Now, before we hear what she found, David, if someone asked you how do you conserve water in your own household, what would you say is the single best thing that you could do?

GREENE: A shorter shower.

VEDANTAM: That's exactly what I would say as well. Now, here's the thing - when Attari matched people's answer with the best science on water conservation, she found something very interesting. Here she is.

SHAHZEEN ATTARI: What we found was roughly 43 percent of our participants said shorter showers followed turning off the water while doing other activities, turning off the water while brushing their teeth. And if you compare these to actions that are truly effective, there's a huge mismatch.

GREENE: Huge mismatch meaning I can take longer showers because taking a shorter shower actually doesn't conserve water? What's going on here?

VEDANTAM: (Laughter). Well, I think you and I were in the right room of the house, David, the bathroom, but we were focused on the wrong appliance. Here's Attari again.

ATTARI: If you look at where we actually use water in the home, the number-one water user in the home are your toilets. So using that information, what are the most effective behaviors people could actually do to decrease water use? And the top behavior is actually installing a low-flush toilet, which would save 19 percent of your indoor water use.

GREENE: But, Shankar, a special low-flush toilet - I mean, I imagine that's something that would be expensive and maybe something many people wouldn't be able to afford, right?

VEDANTAM: Yeah, I think that's right, David. So I think this is the reason people often shrink from making what are called efficiency solutions because when you have an efficiency solution, you actually have to go out and buy something new. They focus on curtailment solutions. So if I just have to take a shorter shower, I don't have to pay anyone anything in order to take a shorter shower.

The hidden bias here, David, is we pay a lot of attention to the cost of something like a new toilet, which is a one-time expense. We are far more likely to live with an inefficient appliance, where the expense mounts over time. Now, of course, the point is if my toilet is inefficient and my other appliances are inefficient, eventually the wasted water is going to end up costing me more than just going out and buying a new toilet.

GREENE: And is that the message, I mean, people in the government should be sending to communities? Spend the money; buy a more efficient appliance. In the long-term, it really will save you some money.

VEDANTAM: I think the government has actually done this in a number of other fields, David, where you actually, for example, you can say only efficient toilets are going to be available for sale in the market and you try and take everything else off the market. You could also subsidize the cost of the efficient appliance, as the government has done with compact fluorescent light bulbs, for example. And the third thing you can do is actually try and apply subtle psychological pressure on people. You could tell them look, all your neighbors have installed the high-efficiency toilet and are saving tons of money. Wouldn't you like to be like them?

GREENE: Save money and do your part.

VEDANTAM: Exactly.

GREENE: Shankar, thanks as always.

VEDANTAM: Thank you, David.

GREENE: That's Shankar Vedantam. He regularly joins us on the program to talk about social science research. You can find him on Twitter - @hiddenbrain. You can find this program - @MorningEdition.


JOHNNY CASH: (Singing) I've been flushed from the bathroom of your heart. In the garbage disposal of your dreams, I've been ground up, dear. In the river of your plans, I'm up the creek. Up the elevator of your future, I've been shafted.

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