Page 138 - Health, Population and Environment Education 9

Surface water
The water which is found on the earth’s surface
is called surface water. Rivers, ponds, lakes, sea
and ocean are some examples of surface water.
Rain is the main source of surface water. There are
around six thousands rivers in Nepal as the main
sources of surface water. The volume of such
water increases in rainy season and decreases in
dry season. However, the big and perennial rivers
like Koshi, Gandaki and Karnali which spring Fig: 8
from the Himalayan region contain large volume
of water throughout the year.

Underground water
Underground water is the water which is found
under the ground. It is extracted by digging
well or through deep boring. Well, pumps and
kuwa are some examples of underground water.
According to the report of ICIMOD (International
Center for Integrated Mountain Development)
and ADB (Asian Development Bank), there is
about 12 cubic kiloliter of underground water in
Nepal. In Nepal, underground water is available
50 feet below in Bhabar region and 5 to 10 feet Fig: 9
below in the mid Terai region.

Importance of water
i. Sustaining life
Water is one of the very basic needs for sustaining life. We cannot live without water.
Fresh and safe drinking water is directly related to our health and life.

ii. Performing daily activities
Most of our daily activities require the use of water. Water is needed to cook food, take
bath and wash clothes, clean utensils and so on.

iii. Hydropower production
Water resource is one of the main resources for
producing energy. Big and fast flowing rivers
are suitable for hydro power production.

Fig: 10
138 GREEN Environment Population and Health Education Book-9