Our rivers are polluted to hell, our oceans have floating shit and plastic in them. Our ground water is riddled with antibiotics, medicine, plastics, you name it.

There's many things wrong ecologically with the world due to pollution and waste. This is not a climate change thread but specifically trying to address the waste problem.

In the old times, you could drink water from any stream or river, now it's basically a death wish.
How can science deal with the plastics and medicine problems ruining our water supply?
How to deal with chemicals?
actually even more important, for thousands upon thousands of chemicals and medicines there's no limit set as of now, mostly because there are so many and no one knows how dangerous they are.

What solutions do you know of, or are proposed to fix This?
I know ships and people are trying to fish out plastic but that's a secondary solution, although obviously they should be mentioned. What primary solutions would you know except for banning plastics and medicines which could keep those out of our natural water supply?
>pic related, it's nature