Water Recycling And Trust
I was talking to some folks yesterday about this, and I was struck by their strong "economic" perspective. They had complete faith in the science that said the treated water would be clean, and therefore complete faith in the project. They attributed opposition to ignorant knee-jerk "eww, sewage water" reactions, and therefore called into question the propriety of using more democratic decision-making (such as a referendum) on an issue like this.
In this case, I'm happy to basically trust the science that says the sewage water can be cleaned adequately, because water treatment is the sort of narrowly-defined engineering problem that technical risk assessment works best on. (I was surprised, however, when in another context my interlocutors cited as incontrovertible fact a study that pinpointed a one-in-a-thousand-years probability of a certain parrot being killed by a proposed wind farm -- how on earth can you accurately calculate something like that?) The pressing importance of Australia's water crisis further militates toward limiting the amount of extreme precaution we take with respect to water cleanliness.
But even if we trust the science, there remain important social questions that could justify concern about implementing such a recycling project. Just because some engineers in the lab can clean the water adequately when they're motivated to prove that it can be done, doesn't mean that the sewage treatment plant will always work properly in practice. There are many stories of facilities for the use or treatment of hazardous materials which become a danger because -- through laziness, the pressure for profit, or a desire to look good to one's superiors -- protocols were not followed and the real danger greatly exceeded the theoretical danger. The question here is trust -- can we trust the people executing the water recycling plan to do it properly? Scientific risk assessments mean little when you can't trust the social system that the assessed activity is embedded in.
What's needed is a process of building trust. Perhaps a system can be worked out in which water is reused "down the scale" of cleanliness -- for example, in the way that one of my friends pumps her used laundry water into her toilet. This would have the added advantage of requiring more household-scale infrastructure, rather than big water projects that foster ignorance, dependency, and corruption by removing water users from contact with their water provision and treatment system.