Fun fact (?): The Thames being so gross is one of the reasons modern sewage treatment took off. One of the main tests is designed based on the behavior of the Thames: https://dnr.wisconsin.gov/topic/labCert/BODAbout.html

You can put the water plant at the end of the sewage plant for example: https://en.wikipedia.org/wiki/NEWater but yeah the water body does some of the treatment too.

Thank you shark fucker 420! You will be pleased to know that I'm not even that unique among the turd herders. Plenty of us are 'eccentric'.

No and yes.

Most regulations are based on the assimilation capacity of the receiving body which is nerd talk for "how much pollution the water can take before it starts showing signs of harm". So you treat to that, nature does a bit more, and then the drinking water plant takes water from an ideal place.

Most wastewater plants just speed up nature.

The history of centralized treatment is super fascinating because it centred on what the problems were when it was established (very late 1800-early 1900s) whereas drinking water treatment really has changed more to deal with how our understanding of human health has changed. They don't really match up!

Sorry, I have wastewater autism: direct potable reuse (turning sewage into drinking water) is super rare and they def don't do that at NEORSD.

Almost every time I give a tour someone says something like that and I have to explain sewage is treated and put back into the water body, then a different plant takes the water, treats it, and puts it in the water pipes. (Yes that's just for surface water, but same idea for septic/wells)

The more the merrier.