Obviously the thread on Thames Water never got through your thick skull.
Folk used to piss and shit in the streets. In London, it flowed down the streets and into the Thames. So the Victorians built a sewage system, and although impressive, it was a combined system. That means surface water enters the same sewage system as Grey water (baths, sinks, washing machines) and Black water (Toilets). That idea was replicated across the country, hundreds of thousands of miles of combined system. So when it rains heavily, the overflow is released into rivers. It's always do e that, it will always do that, and it'll continue to go that in the future. New housing estates have separate sewage systems, one for Grey and Black water, and one for surface water.
Now, it doesn't matter if it's shareholders or the public via taxes that foot the bill to take waste and surface water away, and supply clean water, it is impossible to change hundreds of thousands of miles of sewage systems.
So I don't know which retarded idiot told you Thatcher privatising the water boards suddenly put shit in the rivers, it's been like that pre and post Victorian times. And it's still happening today.
If you took the world's most thickest person and multiplied that by 12 billion, you are thicker than that by a country mile.
I assume you're a chav.