Regarding water quality measures to be taken to protect drinking water sustainable sources
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Language: en
Added: Sep 28, 2025
Slides: 60 pages
Slide Content
Presentation by
J.V. Raghavulu
Rtd. Superintending Engineer
QuestionQuestion
1. What is potable water – Define
QuestionQuestion
2. How water sources are getting polluted
in public supplies
QuestionQuestion
3. Mention Various diseases occurring
through contaminated water
QuestionQuestion
8. What are the bacteriological standards
of water as per code?
QuestionQuestion
10. Mention chemical parameters and
desirable values of water
Earth’s Total Available WaterEarth’s Total Available Water
Oceans -97.2 %
Glaciers -2.15 %
Ground water-0.625 %
Surface water-0.071 %
Soil moisture-0.005 %
Atmosphere-0.0219 %
Per capita Water Requirement
Drinking 3 Lts
Cooking 5 Lts
Bathing 15 Lts
Utensils & House wash 10 Lts
Toilets & Ablution 10 Lts
Washing cloths & others12 Lts
Total 55 Lts
Protected Water Protected Water
Protected water or wholesome water or safe water
or potable water should be.
1.Free from Pathogenic organism.
2.Clear.
3.Not saline.
4.Free from offensive taste or smell.
5.Free from chemicals that adversely affect the
human health.
Functions of Water Functions of Water
Water is one of the three most needed basic things for the
survival of human beings.
Functions :-
1. All the Chemical changes which occur into cells of the body
takes place in the presence of water.
2. Regulates body temperature.
3. It is the vehicle carrying nitrogenous material and salts to
the kidneys.
4. Water acts as a solvent for all to products of digestion,
holding them in solution – permitting to pass through intestinal
track walls.
5. 90% of water is present in the blood. It carries nutritious
elements to the cells.
6. It is required for life process, for functioning of all organs.
7. Water is an important lubricant, it prevents friction between
moving body parts.
WATER RELATED DISEASESWATER RELATED DISEASES
Water Born
1. Diarrhea
2. Cholera
3. Typhoid
4. Hepatitis A & E
Water Scarce Water Scarce
1. Scabies (పొ
డి కురుపు
/ చ
ర్మకురుపు
)
2. Trachoma (క
ళ్ల వాపు రోగం
)
3.Conjunctivitis (క
న్నుఎర్రబారటం
/కం
టి
COLOURCOLOUR
Colour produced are yellow, green, brown and navy due to:
•Decaying organic matter of vegetable or soil origin
•Colloidal and soluble iron and manganese
•Chromate waste which gives only yellow
BIS STANDARD
Acceptable limit - 5 Hazen units
Permissible limit - 15 Hazen units
Greater than 5 are objectionable in water used for
laundries, dairies, paper, textile and processing industries
TASTE TASTE
• People have different sensitivities to taste
BIS standard Limit: Aggregable
Taste Possible sources
Salty High chloride & Na salts
Bitter Magnesium sulphate
Astringent Hard waters, iron & Mn
Sweet Organic matter
Metallic Fe, Mn, Cu & Zn
ODOURODOUR
Source of Oduors can be due to:
•Presence of Hydrogen Sulphide in water due to septic
sewage, chemical and biological reduction of sulphates
•Contamination by organic matter from sewage, pit
toilets, soils and vegetation
•Contamination by chemicals from industrial sources or
treatment process
•Growth of algae, protozoa and fungi in water
•Contact with painted surfaces
BIS standard Limit: Aggregable
TURBIDITYTURBIDITY
•Turbidity is measure of the transparency
or murkiness of water
•It is caused by Suspended solids such as
silt and clay, living or dead algae
Acceptable limit: 1 NTU
Permissible limit: 5 NTU
pHpH
•It describes intensity of acidity or alkalinity
and defined as negative logarithm of
hydrogen ion concentration
•Water outside the range of pH 6 to 9 is
likely to be contaminated due to acidic or
alkaline wastes.
Acceptable limit: 6.5 to 8.5
Permissible limit: no relaxation
pHpH
TOTAL DISSOLVED SOLIDSTOTAL DISSOLVED SOLIDS
•Dissolved minerals present in water
Acceptable limit is : 500 mg/L
Permissible limit is : 2000 mg/L
Chemical ParametersChemical Parameters
1. TOTAL ALKALINITY
2. TOTAL HARDNESS
3. CHLORIDE
4. CALCIUM
5. MAGNESIUM
6. SULPHATE
7. IRON
Total AlkalinityTotal Alkalinity
•The alkalinity in natural water due to the
salts of carbonate, bicarbonate, borates,
silicates and phosphates along with
hydroxyl ions in free state
BIS Standard:
Acceptable Limit : 200 mg/lit
Permissible Limit : 600 mg/lit
Total HardnessTotal Hardness
•Water hardness is the traditional measure of the
capacity of water to react with soap
•The principal hardness causing ions are Ca & Mg.
BIS Standard:
Acceptable limit: 200mg/lit
Permissible limit: 600mg/lit
ChlorideChloride
•Chloride ion is generally present in natural waters
•Presence of chloride can be attributed in dissolution of
salts deposits, discharge of effluents from chemical
industries, irrigation drinage and sea water intrusion in
coastal areas
•High chloride value is deleterious effect on metallic
pipes and structures
BIS Standard:
Desirable limit: 250mg/lit
Permissible :1000 mg/lit
IRONIRON
•Iron may be found as naturally occurring element in
surface and ground water
•It is considered an important part of every one’s diet
•Excess qty. of Iron gives bitter astringent taste to
water
•Excess iron in water will cause reddish brown
staining of laundry, dishes and utensils
•Food cooked in such water may also have slight
colour change
BIS Standard Limit :
Desirable : 0.3 mg/lit
Permissible : no relaxation
FLUORIDEFLUORIDE
•Fluoride is naturally occurring ion in geological formation
•When water comes in contact with high fluoride containing rocks
the fluoride may get dissolved in water
•Excessive fluoride in water is extremely fatal, causing diseases like
Fluorosis, which effect teeth, skeletal & non skeletal parts of the
body
•Limitation of movement of joints and spine & inability to walk and
crippling
BIS Standard :
Acceptable limit: 0.5mg/lit
Permissible limit: 1.5 mg/lit
NITRATENITRATE
•Nitrate occurs elevated levels in ground water usually
result from human activities such as overuse of
chemical fertilizers and improper disposal of human
and animal wastes
•Nitrates are extremely soluble in water and can move
easily through soil into the drinking water
•Excess nitrates causes infantile methemoglobinemia
in infants
BIS Standard :
Acceptable limit : 45 mg/lit
Permissible limit : No relaxation
Bacteriological Parameters
Organism Requirements
All water intended for drinking
•E.coli or thermotolerant coliform
bacteria
•Shall not be detectable in any
100 ml sample
Treated water entering the
distribution system:
•E.coli or thermotolerant coliform
bacteria
•Total coliform bacteria
•Shall not be detectable in any
100 ml sample
•Shall not be detectable in any
100 ml sample
Treated water in the distribution
system
•E.coli or thermotolerant coliform
bacteria
•Total coliform bacteria
•Shall not be detectable in any
100 ml sample
•Shall not be detectable in any
100 ml sample
DRINKING WATER STANDARDS (IS 10500)DRINKING WATER STANDARDS (IS 10500)
Sr. NoParameter
Bureau of Indian Standards
Desirable LimitPermissible Limit
1Colour 5 Hazen units15 Hazen units
2Odour Agreeable Agreeable
3Taste Agreeable Agreeable
4Turbidity 1 NTU 5 NTU
5pH Value 6.5 to 8.5 No relaxation
6Total Hardness200 mg/l 600 mg/l
7Iron 0.3 No relaxation
8Chloride 250 mg/l 1000 mg/l
9
Residual
Chlorine
0.2 mg/l 1 mg/l
10Fluoride 1.0 mg/l 1.5 mg/l
11Dissolved solids500 mg/l 2000 mg/l
12Calcium 75 mg/l 200 mg/l
13Sulphate 200 mg/l 400 mg/l
14Nitrate 45 mg/l No relaxation
15Alkalinity 200 mg/l 600 mg/l
PARAMETERS BY FTKPARAMETERS BY FTK
Chemical:
1. Turbidity
2. pH
3. Total Alkalinity
4. Chloride
5. Total hardness
6. Fluoride
7. Nitrate
8. Iron Test
9. Residual Chlorine
Bacteriological :
H
2S Vial Test
COMPOSITIO COMPOSITION OF H S
₂
- STRIP
MEDIUM*
Peptone 20 g
Dipotassium Hydrogen PO
₄
1.5 g
Ferric Ammonium Citrate 0.75 g
Sodium thiosulphate 1 g
Teepol 1 ml
L-Cystiene HCl 0.25 g
Water 50 ml
* Concentrated 20x
DISINFECTIONDISINFECTION
Types of DisinfectantsTypes of Disinfectants
Chemical
1.Chlorine and Chlorine Compounds.
2.Iodine.
3.Potassium Permanganate.
4.Ozone.
Non Chemical.
1.Boiling.
2.UV & Gamma Radiation.
Treatment with Ozone
1.Faintly blue gas.
2.Unstable allotropic form.
3. Produced by passing a high-tension electric
current through a stream of air in a closed
chamber.
4. Ozone and Chlorine are quite competitive
disinfectants.
5. Chlorine is however preferred and almost
universally adopted.
Treatment with Ozone
Advantages.
1.Being unstable, noting remains in water.
2.Ozonized water becomes tasty unlike chlorinated
water.
Disadvantages.
1.Much costlier than chlorination.
2.Power Supply required.
3.No residuals maintained – Best for bottling.
4.Cannot be supplied in Cylinders like chlorine –
requires Ozoniser plants to be installed.
UV RaysUV Rays
1.invisible light rays.
2.They are basically found in sun light.
3.Produced by passing electric current through
Mercury enclosed in quartz bulb.
4. Highly effective in killing of all bacteria.
5.Water is passed several times around the quartz
bulbs emitting such rays.
6.Very costly – needs technical know.
7.Not suitable for large scale treatments.
Chlorine is best disinfectant Chlorine is best disinfectant
1.Chlorine in any form is most common disinfectants.
2.It destroys the enzymes, essential for the existence
of micro organism.
3.It destroys taste and colour producing constituents.
4.Controls Alge.
5.It also aids coagulation.
6.There is provision to check the residuals.
7.If residual remains in water it encounters further
contamination.
8.Invariably used throughout the world.
Forms of Chlorine Application Forms of Chlorine Application
1.Chlorine Gas.
2.Chlorinated lime.
3.High test hypochlorite.
4.Sodium hypochlorite (Liquid chlorine)
5.Chlorine dioxide.
CHLORINE DEMAND CHLORINE DEMAND
Types of Chlorination
1.Plain chlorination.
2.Pre chlorination.
3.Post chlorination.
4.Break point - chlorination.
5.Super chlorination.
6.De chlorination.
Testing of Chlorine Residuals Testing of Chlorine Residuals
1.Orthotolidine
2.OTA
3.DPD Test Diethyle – Phenyle – Diamine
4.Starch Iodide Test