Explain two causes of pollution of water bodies with examples.

Two causes of pollution of water bodies are:

1. Urbanisation — Rapid urbanisation in India during the recent decades has given rise to a number of environmental problems such as water supply, waste water generation and its collection, treatment and disposal. For example, pollution in major rivers.
2. Oil spills — Waste oil from city drains, tankers and leakage from oil wells cause the oil to seep into the sea and pollute water. Massive oil spills at sea by huge oil tankers severely pollute the oceans.