The Newater visitor center includes a small-scale version of the vast treatment plant that I ride past every day. They use a three-stage process: micro-filtration, reverse-osmosis, and UV filtration.
Bundles of tiny, porous tubes which take up filtered water. Some unspecified percentage of the water left outside the tubes is ‘backwash’ and discarded into the ocean. This section of the tour is accompanied by a charming video which shows little animated protozoans bashing into the outsides of the tubes and turning away.
A few of the zillion r/o chambers which make up phase two
Another pleasing video and illustration scales the pores in the r/o membrane to the size of tennis balls, and presents water molecules as ping-pong balls. In the video, a bacterium is illustrated by a large-sized building whacking into an enormous tennis net.
Here, suddenly, I wonder who the target audience of this presentation is. Is ‘Estrogen Endocrine Disruptor’ really #3 on the worry list after ‘virus’ and ‘bacteria?’
Unsurprisingly, photos that I took of the Ultraviolet phase were hopelessly overexposed. In any case the tour guide conceded that there is no scientific basis for the UV phase (since we’ve already established that all microorganisms have been filtered out earlier in the process) and it’s just there as a safeguard and/or security blanket.
Most of the now-ultra-pure water is piped to semiconductor plants and other industries that need distilled or deionized water anyway. A tiny bit is pumped into the public reservoirs, but the long term plan is to pump increasingly more water back into the main water supply. I guess that’s so that right now they can tell people that there’s “only a little bit of pee” in the water and, a decade from now can say “hey, you’ve been drinking pee for years, what’s the big deal if it’s a little more?”
Of course, I’m used to drinking out of the Mississippi, so I have a hard time taking the gross-out potential of recycled water seriously.
The pure product doesn’t taste so great, though.