How do people use and misuse rivers and how does water become polluted?

People use rivers for transporting goods and services, irrigation, and fish farming.

people misuse rivers by throwing there trash in the river or nearby and the wind carries it to the river. also factories that are close to a river will often dump the waste products of whatever they are manufacturing, this can include oils, trash, metals... etc. and boats that travel to import or export pollute the water from there engine(s).

Explanation: there are many uses for rivers but a lot of them have to include extra steps to counteract the negative outputs of pollution.