EVS Answer the following in one sentence

Alum is used in water to get rid of the bad odour.

Settling – Oxygenating – Filtration – Chlorination.

Filtration, purification, chlorination

Rainwater collected in reservoirs and lakes is used for public water supply system. Water from lakes like Tansa, Tulsi and Vihar supply water to Mumbai city.

Rainwater from roof tops is drained into large tanks placed besides the building thus saving rain water.

When it is not possible to build large dams then people and government come together to build smaller reservoirs, contour bunding, constructing bunds on smaller streams or dig wells in river beds to increase the groundwater storage level.

A famine is a natural disaster, where the affected area does not receive any rain, so land get dry and there is no water for humans, animals as well as agriculture.

We must crush and throw the empty drinking water bottles into a bin, so that it cannot be reused.

The date of bottling and the period for which the water can be safely used is printed on the bottle. Therefore, it is important to read the information when we buy a bottle of drinking water.

If large quantities of impurities get mixed with river water, the proportion of oxygen dissolved in the water is reduced and this is a threat to aquatic living things.

If this waste water is let into water bodies as it is then the water bodies become polluted and that is dangerous. That is why it is compulsory for factory owners to treat the water before letting it out.

Waste water from industries is more likely to contain poisonous substances.

Sewage water carries microorganisms that spread diseases.

The waste water of a city or town is collected and let into a water body at a convenient location.