3. Water pollution is the contamination of water by sewage, toxic chemicals, metals, oils, or other substances. It can affect such surface waters as rivers, lakes, and oceans, as well as the water beneath the earth's surface, called ground water. Chemical and oil spills can also cause devastating water pollution that kills fish, aquatic plants, water birds, shellfish, and other wildlife. What is water pollution?

6. Diagram of how water get drained away and polluted