This is an academic document for the nursing student.

1. s

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

3. General Objective
• At the end of this session BSc Nursing 1st year
students will be able to explain about hardness
of water and its treatment procedures.

4. Specific Objectives
At the end of this session BSc 1st year students will
be able to:
• explain about tube well.
• introduce spring.
• list the impurities of spring water.
• introduce hardness of water.
• describe the disadvantages of hardness of water.
• explain the method to remove hardness of water
• list the method of purification of water.

5. Sources of ground water
• Wells
• Spring

6. Tube Well

7. Introduction
• Tube well is the long pipe sunk in the ground
intercepting one or more water bearing strata.
• As compared to open well their diameter is
less about 80-600mm.
• They have high discharge capacity than the
open wells.
• Water is usually extracted in the high flow
with the help of the pump.

8. Types of tube well
• Shallow tube well
• Deep tube well

9. Shallow tube well
• They are suitable when the distance of the
water from the source of ground is not more
than 30 meters deep.
• They discharge the water at 20m3 per hour.
• It can be bored in gravel, coarse or chalks but
clay soil or fine sand is not suitable.
• They however do not assure constant supply of
water.

10. Deep tube well
• Deep tube wells are sunk by drilling through
successive substra or gravel rock until a
suitable supply of ground water is located.
• They may be 600 meters deep and require a
complicated mechanical drilling equipment
and skilled engineering equipment.
• They discharge the water at 800m3 per hour.
• They are costly to construct but provides ideal
supply.

12. Spring

14. Introduction
• When the ground water comes into surface &
flows freely under natural pressure, it is called
a spring.
• When the groundwater table reaches above the
surface level springs are formed.
• Minerals become dissolved in the water as it
moves through the underground rocks.
• So the concept of mineral water arise from
spring water.

15. Introduction Cont’d
There are generally two types of spring:
• Shallow Spring
• Deep Spring

16. Shallow Spring
• They are the outlet of limited collection of
ground water.
• They are usually intermittent, may quickly dry
during summer season.

19. Deep Spring
• These are deep sealed springs issuing water
supply through cracks or fissures in the soil.
• They offer a continuous supply of water do not
show seasonal fluctuations in the flow of
water.
• They are a good source of water supply to
small communities.

21. Impurities

22. Hardness of water
• Hardness may be defined as the soap
destroying power of the water.
• The consumer considers water hard if large
amount of soap is required to produce lather.
• In the scientific terms hardness of water is
generally described as the amount of dissolved
calcium and magnesium in water.

23. Introduction cont’d
The hardness of water is mainly caused by
dissolved compounds they are:
• Calcium bicarbonate
• Magnesium bicarbonate
• Calcium sulphate
• Magnesium sulphate
• Calcium chloride
• Magnesium chloride

24. Types of Hardness
Temporary hardness
• Temporary hardness is mainly caused by the
bicarbonates of calcium and magnesium.
• It can be easily removed by boiling of water.

25. Types of Hardness Cont’d
Permanent hardness
• Permanent hardness is due to presence of
sulfates and chlorides of calcium and
magnesium in water.
• Permanent hardness is not removed by simple
boiling of water but it requires some complex
operations.

26. Disadvantages of Hardness
• Hardness of water consumes more soap and
detergent.
• When hard water is heated the carbonates are
precipitated.
• Bring about furring or scaling of the boilers.
• Great fuel consumption,
• Loss of efficiency and sometimes cause boiler
explosion.

27. Disadvantages of Hardness Cont’d
• Hard water adversely affects cooking.
• Fabrics washed in hard water do not have long
life.
• There are many industrial processes in which
hard water in unsuited and give rise to
economic loss.
• Hardness shortens life of pipes and fixtures

30. Level of softness and hardness of
water
Classification Level of hardness mEq/liter
Soft Water Less than 1 (<50mg/L)
Moderately Hard 1-3(50-150mg/L)
Hard Water 3-6(50-300mg/L)
Very Hard Water Over 6(>300mg/L)

31. Treatment of hardness of water
• Boiling
• Addition of lime
• Addition of Sodium Bicarbonate
• Base exchange process

32. Boiling
• This removes temporary hardness by expelling
carbon-dioxide and precipitating the insoluble
calcium carbonate. It is expensive method to
soften water on large scale.

33. Addition of lime
• Lime absorbs carbon-dioxide and precipitates
the insoluble calcium carbonate.

34. Addition of Sodium Carbonate
• Sodium carbonate removes both temporary
and permanent hardness.

35. Base exchange process
• In the treatment of large water supplies the
permutit process is used.
• Sodium permutit is a complex compound of
sodium, aluminium and silica.
• It has the property of exchanging the sodium
cation for calcium and magnesium ion in
water.

36. Base exchange process Cont’d
• When hard water is passed through the
permutit the calcium and magnesium ions is
entirely removed by base exchange and
sodium permutit is finally converted into
calcium and magnesium permutit.

37. Purification of water in small scale

39. Boiling
• Boiling is a satisfactory method of purifying
water for household purposes.
• To be effective, the water must be brought to a
"rolling boil" for upto 20 minutes.
• It kills bacteria, spores, cysts and ova and
yields sterilized water.
• It removes temporary hardness.

40. Introduction cont’d
• The taste of water is altered, but this is
harmless.
• Boiling is an excellent method of purifying
water.

42. Storage technique of boiled water
• Boiling offers no residual protection against
subsequent microbial contamination.
• Water should be boiled preferably in the same
container in which it is to be stored to avoid
contamination during storage.
• Store boiled water in clean, disinfected,
plastic, food-grade bottles or containers.

43. Storage Technique Cont’d
• Make sure they’re airtight, sturdy, and won’t
break easily.
• Wash out the storage containers with hot,
soapy tap water and rinse them.
• Don’t use bleach that is scented, color-safe, or
with added cleansers.
• Store water in a cool, dark place. Put the
containers in dark, plastic bags to keep the
light out.

44. Storage Technique Cont’d
• Boiled water can be stored in a container in
refrigerator for 3 days and in room temperature
for 24hrs.
• If the water boiled is entirely pure, distilled,
de-ionized water, it is okay to re-boil the water.
If it is a faucet or tap water, it contains
dissolved gas and minerals, rendering it unsafe
to re-boil.

46. Post - Test

47. Summary

48. 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

49. • Prabhakara, G.N., (2005). “Textbook of
Community Health for Nurses”, 1st edition,
Peepee publishers and distributors Pvt. Ltd.s
• Retrieved from
https://www.nationalgeographic.org/encyclop
edia/surface-water/ on 12/7/2021

50. Home-Assignment
• Describe about method of water purification
used in your home.

51. Plan for next class
• On our coming class we will study about
purification of water in small scale.