Question: why is the water polluted?

Hussain Jaffery answered on 16 Nov 2015:

Water pollution can occur for different reasons in different places, but almost certainly humans are responsible for every case. There are many cases of fresh water pollution of lakes and rivers, but the ocean which is made of salty water, by far receives the bulk of our waste.

Major causes for ocean pollution include:

Too much carbon dioxide in the atmosphere, which dissolves into the ocean, making it acidic and killing corals and the fish that depend on coral.

Industrial process and human waste. A lot of the water that flow into the ocean is not treated before being dumped into the oceans, which can cause poisoning of the marine life in the area,

Excessive production of plastics and their improper disposal. Plastics, including fix drink bottles, take million of years to degrade, and if not recycled, can be eventually found floating in the sea. Plastics break into smaller pieces and marine life can accidentally swallow it and get poisoned by it.

There are efforts to clean up our act, but it will take time!

The freshwater we drink, however, is carefully cleaned and managed, thankfully.