Causes of water pollution are
(i) Rainwater dissolves the fertilizers and pesticides from agricultural fields and takes them to nearby water bodies, where it causes harmful effects on aquatic life.
(ii) Dumping of sewage and other wastes into water bodies. .
(iii) Industries use water for cooling various machines and later release hot water into water bodies. This causes sudden change in temperature of water that affects the breeding of aquatic organisms.
Ways to reduce water pollution are
(i) If sewage and garbage generated by homes and industries is treated properly before discharging into water sources, it will reduce water pollution and cause less harm to the aquatic life.
(ii) If hot water generated by the industries is collected at a common place, allowed to cool and then discharged in water bodies, it will not affect the breeding capacity of aquatic organisms.
(iii) If commercial areas, factories and industries are
shifted to the isolated area far away from residential areas, it can reduce the effect of water pollution on nearby water resources.