Water

[Rob]

What other water treatment technologies would work? I have a feeling turning brown water into drinking water would not be 'palatable' to most people.

This article talks about a few of the newer technologies available.
https://www.amtaorg.com/Water_Desali...Processes.html

This is the Carlsbad CA plant webpage. Lots of info about how it works, not so much about waste products. Not sure if there is anywhere in the world more concerned about the environment than the Country of California - my guess would be that they have mitigated most of the environmental concerns either with this state of the art technology or through other means.
http://carlsbaddesal.com/

The US EPA seems to disagree. They state "Wastewater treatment facilities in the United States process approximately 34 billion gallons of wastewater every day. Wastewater contains nitrogen and phosphorus from human waste, food and certain soaps and detergents."

https://www.epa.gov/nutrientpollutio...ons-wastewater

Most homes and businesses in the US handle their waste water this way.

In contrast all the desalination plants worldwide produce less than 23 billion gallons a day. USA water treatment alone processes one third more water than all desalination plants combined.

Interesting that you have to "guess" about the waste products at Carlsbad. Why don't they explain on their site more about this important issue?

Desalination is just not ready for prime time yet...

The Roaring River plant makes much more economic sense.

And waste water MUST be treated anyway. You can't just pump into the rivers or sea untreated. That is a dangerous lesson mankind learned the hard way.