Orange County in SoCal has been doing this for a few years. They start with the type of treated sewage you mention above; then they microfilter it; then they d

Orange County in SoCal has been doing this for a few years. They start with the type of treated sewage you mention above; then they microfilter it; then they do reverse osmosis; then they treat it with UV and H2O2; then they use it to recharge the aquifer (where it takes some time to trickle through before they pump it back out of the wells). http://www.gwrsystem.com/the-process.html http://www.gwrsystem.com/the-process.html