Brent Haddad studies water in a place where water is often in short supply: California.
Haddad is a professor of environmental studies at the University of California, Santa Cruz. About 14 years ago, he became very interested in the issue of water reuse.
At the time, a number of California’s local water agencies were proposing a different approach to the state’s perennial water problems. They wanted to build plants that would clean local waste water — a.k.a. sewage water — and after that cleaning, make it available as drinking water. But, says Haddad, these proposals were consistently shot down by an unwilling public.
From the perspective of the water engineers Haddad was talking with, this kind of reuse was a no-brainer. The benefits were clear and the science suggested that the water would be safe. Clean Water Action, an environmental activist group, also supports reuse for drinking water, though it thinks there should be national regulatory standards.
But according to Haddad, no matter what the scientists or environmental organizations said, the public saw it differently: They thought that directly reusing former sewage water was just plain gross.
Which is why Haddad turned to a nonprofit called The WateReuse Foundation for funding for a study. He wanted to figure out more about the public’s response to reused water, and for that he needed additional people. This was a job, Haddad concluded, for psychologists.
Psychological Contagion
Carol Nemeroff is one of the psychologists whom Haddad recruited to help him with his research. She works at the University of Southern Maine and studies psychological contagion. The term refers to the habit we all have of thinking — consciously or not — that once something has had contact with another thing, their parts are in some way joined.
Contagion thinking isn’t always negative. Often, we think that it is some essence of goodness that has somehow been transmitted to an object — think of a holy relic or a piece of family jewelry.
And according to Nemeroff, there are very good reasons why people think like this. As a basic rule of thumb for making decisions, when we’re uncertain about realities in the world, contagion thinking has probably served us well. “If it’s icky, don’t touch it,” says Nemeroff.
The researchers led by Haddad wanted to figure out more about how our beliefs about contagion in water work. And so they recruited more than 2,000 people and gave them a series of detailed questionnaires that sought to break down exactly what you would have to do to waste water to make it acceptable to the public to drink. The conclusion?
“It is quite difficult to get the cognitive sewage out of the water, even after the real sewage is gone,” Nemeroff says.
Around 60 percent of people are unwilling to drink water that has had direct contact with sewage, according to their research.