Found this article on how we might find ourselves drinking water reclaimed from sewage.
The problem stems from less-reliable precipitation patterns. In other words, climate change is changing our rainfall numbers.

While it sounds horrific to think of drinking sewer water, the filtration technology is available to accomplish the task. “Protecting the Sewershed.”
Personally I would not be comfortable relying on just the water supplies of municipalities to correctly handle this job. Government can fall short of a doing a good job. Remember Flint MI?
Best to have a good whole house water filter system installed too.
Nice video on the idea of drinking repurposed sewer water.
If you have not checked out our water filtration system, do so now.
And here is an article on how our systems deal with hard water issues.
If you would like to do more research and see a lot of interesting videos we have done on water quality, water filtration, etc., check this out.

Article source: https://science.sciencemag.org/content/369/6510/1429