Question

is it possible for river water to get cleaned naturally by the processes that are similar to those adopted in a wastewater treatment plant? If so how

Answer 1

HEY THERE
YES IT IS POSSIBLE
WAYS TO DO IT

Dredging of the contaminated sludge from the river bad

Handling it to the river banks for treatment.

Establishing sludge cleaning processes

Converting it to useful soil

If required extracting precious material out of the sludge

Treating the contaminating sources to the river and return clean water to the river.
I DON'T KNOW MUCH. SORRY I WAS ABLE TO GATHER ONLY THIS MUCH INFORMATION