With the Southwestern drought and Western growth continuing, the dry and arcane subject of water policy is suddenly … sexy. And the new new thing in Western water supply is the recycling of sewage plant effluent as drinking water.

After having effluent-recycling proposals shot down a couple of times by opponents calling them “toilet to tap” boondoggles, San Diego is once again studying effluent purification to supplement drinking water supplies, according to the brilliant online news site voiceofsandiego.org. If there’s one more winter of subnormal Sierra snowpack, it seems, San Diego will face mandatory water rationing.

And the south suburbs of Denver are looking at the possibility of cleaning wastewater sufficiently to put it into their drinking water supply. And why is that? Here’s how the Denver Post puts it:

The Water Supply Initiative estimated in 2005 that Colorado likely could add another 2.8 million people by 2030, raising the demand for water by another 202 million gallons of water a year.

The south metro region is being forced to look for new, costly water supplies. Most of the region relies on aquifers that are running dry.

A 2003 regional study by water providers found that shortages and higher costs would be commonplace for customers in as little as 20 years.

Of course, High Country News has, as usual, been an early trend-spotter on the toilet-to-tap issue, as evidenced by Peter Friederici’s sprightly and authoritative cover story on the phenomenon, “Facing the Yuck Factor.”