This document discusses different sources of water. It begins by stating the general and specific objectives of the session which are to introduce various water sources such as rainwater, groundwater, impounding reservoirs, rivers, and tanks. It then provides details about each source: Rainwater is the primary source that replenishes groundwater and surface water. Surface water includes impounding reservoirs, rivers, ponds and lakes. Impounding reservoirs are artificial lakes constructed to store surface water. Rivers and their characteristics are also described. The document concludes by defining groundwater and its advantages over surface water sources.

2. UNIT-8
WATER
Prepared By - Ajara Bhattarai
Roll No-21
BNS2nd Year
T/L Practicum
Maharajgunj Nursing Campus

4. General Objective
• At the end of this session BSc Nursing 1st year
students will be able to explain about sources
of water.

5. Specific Objectives
At the end of this session BSc 1st year students will
be able to:
• introduce sources water.
• explain about rainwater.
• introduce ground water and its sources.
• explain about impounding reservoir.
• explain about river.
• explain about tanks.
• introduce ground water.

7. Sources of water
The main sources of water are:
• Rain
• Surface water
• Ground water

9. Rain
• Rain is the prime source of all forms of
water.
• A part of rainwater sinks to form a
ground water.
• This water also takes part in water cycle.

10. Characteristics of rainwater

11. Characteristics cont’d
• The amount of rainwater collected will depend
on the rainfall 1cm of rainfall over 1sq.m will
yield 10lts of water.
• Rainwater is slightly acidic in nature i.e. pH
5.6 and very low in minerals content.

12. Impurities of rainwater
• Rain water tend to become impure as it passes
through the atmosphere.
• The acid rain is the increasing problem of
industrial society.
• Gases sulphur and nitrous oxide are emitted
from power plants that reacts with atmospheric
water, forming sulphuric and nitric acid.

15. Surface water
• Surface water is water in the surface of the
planets e.g river, lakes.
• Surface water originates from rain water.
• Surface water is the residue of precipitation
and melted snow, called runoff.
• As due to climate change there is melting of
glaciers, sea ice which is contributing to rise in
the level of the surface water

16. Surface water cont’d
• Surface water is prone to contamination from
human and animal source.
• It is never safe for human consumption unless
subjected to sanitary protection and
purification before use.
• The vast majority of Nepal’s population
depends upon surface water sources e.g
Sundarijal, Shivapuri etc.

17. Types of Surface water
• Impounding reservoirs
• Rivers and streams
• Tanks, Ponds and lakes.

18. Impounding reservoirs

19. Introduction
• A reservoir with outlets controlled by gates
that release stored surface water as needed.
• May also store water for domestic or
industrial use or for flood control.
• Also known as storage reservoir.
• These are the artificial lakes constructed
usually of earthwork or masonry in which
large quantities of surface water is stored.

20. Introduction cont’d
• Dams built across river, mountains, streams
also provide large reserve of surface water.
• It is also known as embankment pond.
• It helps supply right amount of water at right
places.

22. Characteristics
• It furnish a fairly good quality of water.
• Water is usually clear, palatable and ranks next
to rain water in purity.
• If the surrounding hills are covered with peat
the water usually acquires a brownish color.
• Water is soft and free from pathogenic
organism

23. Impurities
• The water derives impurities from catchment
area, the sources being human habitation and
animal keeping and grazing.
• The mountains streams are thought very pure
though there is no human settlement, there is
possibility of contamination by wild animals.

24. Rivers

25. Introduction
• River water is a surface water source and a
part of the water cycle.
• It can be used for households, irrigation,
processing in industries or for the production
of energy.
• The river water level changes throughout the
year with the different seasons.
• Large catchments influence the river water
level more slowly than small catchments.

26. Characteristics
• River water is turbid during rainy season
though it may be clear during other season.
• Clarity of water is no guarantee that the river
water is safe for drinking.
• River water contains dissolved and suspended
impurities of all types.
• Self purification occurs in river.

28. Impurities
• Rivers have direct contamination between the
people living upside and the downside of the
river.
• The bacterial count including the human
intestinal organism may be very high.
• The customs and habits of people like bathing,
animal washing and disposal of the waste all
add to river water pollution.

29. Tanks

30. Characteristics
• The tank holds water.
• A water tank can be a buried cistern, a water
tower, or at the other extreme it can be a lake.
• Tanks are large excavations in which surface
water is stored.
• They are important source of water supply in
the rural areas of the country.

31. Impurities
• Tanks are recipients of contamination of water
of all sources they are full of slit and colloidal
material especially immediately after the rain.
• The older tanks may be full of aquatic
vegetation.
• Tanks are subjected to unlimited possibility of
contamination.

33. Ground water

34. Introduction
• Rain water percolating in the ground
constitutes ground water.
• Water used by human comes mainly from the
land.
• It is the most practical means of providing
water to small communities.
• It is superior to surface water because the
ground itself provides a means of filtrating
medium.

35. Advantages
• It is likely to be free from pathogenic agents.
• It usually requires no treatment.
• The supply is likely to be certain even during
dry season.
• It is less subjected to contamination.

36. Disadvantages
• It is high in mineral content e.g salts of
calcium and magnesium which makes water
hard.
• It requires pumping or some arrangements to
lift the water.

38. Post - Test

39. Summary

40. References
• Basavanthapa, BT.( 2016). “Community Health Nursing”, 3rd
edition, Jaypee Brothers Medical Publishers(P) ltd.
• Dahal, K. Rai, A.(2012). “A text book of Community Health
Nursing I”, 4th edition, Makalu Publication.
• Park, K.(2021). “Park’s Textbook of Preventive and Social
Medicine”, 26th Edition, M/s Banarsidas Bhanot Publishers
Pune.
• Manandhar, M.(2018). Community Health Nursing, 2nd
edition, Akshav Publication.
• Rao S, B.(2010). Principles of Community Medicine,5th
edition, Aitbs Publishers, page no: Stanhope M. and
Lancaster J.(1984) Community Health Medicine, 2nd edition,
Mosby publisher

41. • Prabhakara, G.N., (2005). “Textbook of Community
Health for Nurses”, 1st edition, Peepee publishers and
distributors Pvt. Ltd.
• Retrieved from
https://www.iwapublishing.com/news/rainwater-why-
it-safe on 12/7/2021
• Retrieved from
https://www.nationalgeographic.org/encyclopedia/surf
ace-water/ on 12/7/2021
• Retrieved from
https://www.sciencedirect.com/topics/engineering/im
pounding-reservoir on 11/7/2021

42. Home-Assignment
• Study about the sources of water.

43. Plan for next class
• On our coming class we will study about
ground water and its sources.