Preservation Of Water Quantity

Name : Class : 2 KRK 2 Subject : Science Kod Evidences : B6D4E1 Subject’s teacher :

Contents :

Bil | Topic | Pages | 1 | Biography | 3 | 2 | Water pollution | 4-10 | 3 | Controlling water pollution | 10-13 | 4 | Purification of water | 13-16 | 5 | Ways of conserving water | 17-23 | 6 | The end | 24 |

Biography Name Class: 2 KRK 2 Date of Birth: Constellation: Libra I/C No: Address 1.1 : Water pollution What is water pollution? Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living thing that drinks or uses or lives it. When humans drink polluted water it often has serious effects on their health. Water pollution can also make water unsuited for the desired use. There are several classes of water pollutants:- 1) Domestic waste Domestic sewage refers to waste water that is discarded from households. Today, many people dump their garbage into streams, lakes, rivers, and seas. This action will bring effect on living things such as choke up streams and rivers, causing flash floods during heavy rain. Moreover, non-biodegradable materials such as plastics cannot be broken down by micro-organisms. They remain in water for a long time. Many seabirds and aquatic animals are downed or wounded when they swallow or get entangled in the materials.

Besides that, untreated sewage refers to wastewater from drains or toilets. It contains substances such as human waste and detergents. The various substances that we use for keeping our houses clean add to water pollution as they contain harmful