WATER POLLUTION.ppt

Water pollution

1. WATER POLLUTION
•Introduction
•SourcesofwaterPollution
•Classificationofwaterpollutants
•WaterQualityStandards
•Effectsofwaterpollution

2. INTRODUCTION
Contamination
Pollution
Pollutants
Video

3. SOURCES OF WATER POLLUTION
Point Source: Any single identifiable source of
pollution from which pollutants are discharged
Non point Source: Sources of pollution are
scattered or diffuse and can not be readily identified

4. Video

5. POINT SOURCE
•Pollutionoccursfromasingle
identifiablesource
•Dischargeofeffluentsoccursat
onepoint
•Effectishigh
•Easiertomanageandcontrol
•Ex.Industries,faultytreatment
plant,oiltankspills,sewer
outfallsetc.
NON POINT SOURCE
•Pollutionoccursthroughmany
scatteredsources
•Causedbydischargeof
pollutantsoverawidearea
•Effectislow
•Verydifficulttomanageand
control
•Ex.Farmingpesticidesand
fertilizers,roadsaltrunoffetc.

6. CLASSIFICATION OF WATER POLLUTANTS
Onthebasisoftheirsource
(a)NaturalPollutants:Thepollutantsreleasedin
environmentduetonaturalactivitieslikeVolcanic
eruption,forestfire,storms,decompositionetc.
(a)Man-made(anthropogenic)Pollutant:The
pollutantsproducedbydifferenthumanactivitieslike,
Industrialisation,urbanisation,deforestation,mining,use
offertilizersandpesticidesetc.

7. CLASSIFICATION OF WATER POLLUTANTS
Onthebasisofnatureofmaterial
(a)Biodegradable:Thepollutantswhichare
decomposednaturally
Ex.Sewage,wood,paper,garbage,cardboardetc.
(a)Non-biodegradable:Thepollutantswhichcannot
bedecomposednaturallyordegradeatveryslowrate
Ex.DDT,Plastic,glass,E-wasteetc

8. CLASSIFICATION OF WATER POLLUTANTS
Onthebasisoftheirconcentrationinnature
(a)Quantitativepollutants:Thepollutantswhich
normallyoccurinenvironmentbutbecomepollutantsif
theirconcentrationincreasesthanallowablelimit.
Ex.CO
2inatmosphere
(a)Qualitativepollutants:Thepollutantswhichdo
notoccurnaturallyinenvironmentandaddedbyhuman
activities.
Ex.Pesticides,Insecticidesetc.

9. CLASSIFICATION OF WATER POLLUTANTS
Onthebasisofformofpollutant
(a)Primarypollutants:Thesubstancewhichremainin
sameforminenvironment
-Also,calledasdirectpollutants
Ex.Smoke,dust,ash,hydrocarbonetc
(a)Secondarypollutants:Thesubstancewhichare
formedfromprimarypollutants.
-Consideredmoretoxicthanprimarypollutants
Ex.SO
3,Ketones,Ozone,aldehydes,PAN(Peroxyacyle
nitrate)etc.
VIDEO

10. WATER QUALITY STANDARDS
•Thewaterqualityisphysical,chemicaland
biologicalpropertiesofwater.
•Thewaterqualitydefinesonthebasisofits
intendeduse.
•Differenttypeofwateruserequiredifferentlevel
ofwaterpuritylike,drinkingwaterrequires
higheststandardsofpuritywhileirrigationand
hydropowergenerationrequireslowerquality
standards.

11. WATER QUALITY STANDARDS
1.Physical Parameters:
-The parameters which respond to the sense of
sight, taste and smell.
-The user can judge water quality by its physical
characteristics
2.Chemical Parameters:
3.Biological Parameters:

12. WATER QUALITY STANDARDS
PHYSICAL
PARAMETERS
CHEMICAL
PARAMETERS
BIOLOGICAL
PARAMETERS
-Colour
-Odour and taste
-Suspended solids
-Turbidity
-Temperature
-Total dissolved
solids (TDS)
-pH
-Acidity
-Alkalinity
-Hardness
-Chlorides
-Fluorides
-Metals
-Organic matter
Pathogens
-Bacteria
-Viruses
-Protozoa

13. WATER QUALITY STANDARDS
1.Indian Standard Institution (ISI)
2.World Health Organization (WHO)
3.Indian Council of Medical Research (ICMR)
4.United States Public Health Services (USPHS)

14. Physical Parameters
Colour
•Purewateriscolorless.Thereforeanytypesofcolorappearanceinwater
indicateswaterpollution.
•Naturalwatersystemisoftencoloredbyforeignmaterial.Ifcolorisdueto
suspendedmaterial,itiscalledasapparentcolor.Colorgivenbydissolved
materialthatremainsevenafterremovalofsuspendedmaterialiscalled
truecolororrealcolor
•Materialsdecayedfromorganicmatter,namely,vegetationandinorganic
mattersuchassoil,stones,androcksimpartcolortowater,whichis
objectionableforestheticreasons,notforhealthreason.
•ColorismeasuredbyTintometer.Permissiblelimitis15Hazenunits.

15. Physical Parameters
Taste & Odour
•Purewaterisalwaystastelessandodorless.Thereforeifanytypesoftasteand
odorispresent,itindicateswaterpollution.
•Watertasteandodormaydevelopsduetonaturalorartificialregions.
•Artificialregionfortasteandodorinwaterisdueto(chlorination).Somenatural
impuritiesdissolvedinwatercanalsogivetasteandodor.
•InorganicsaltssuchasNaCl,KCletcdissolveinwatergivetastewhereas
compoundslikeH
2Scangivebothtasteandodor.
•Compoundsgivingtasteandodortowatermaybetoxictoconsumer,sodrinking
watershouldbetastelessandodourless.

16. Physical Parameters
Suspended Solids
•TotalSuspendedSolids(TSS)aresolidsinwaterthatcanbetrappedbya
filter.TSScanincludeawidevarietyofmaterial,suchassilt,decayingplant
andanimalmatter,industrialwastes,andsewage.
•Highconcentrationsofsuspendedsolidscancausemanyproblemsfor
streamhealthandaquaticlife.
•Totalsuspendedsolids(TSS)areparticlesthatarelargerthan2microns
foundinthewatercolumn.Anythingsmallerthan2microns(averagefilter
size)isconsideredadissolvedsolid.

17. Physical Parameters
Suspended Solids
•HighTSScanblocklightfromreachingsubmergedvegetation.Asthe
amountoflightpassingthroughthewaterisreduced,photosynthesis
slowsdown.Reducedratesofphotosynthesiscauseslessdissolved
oxygentobereleasedintothewaterbyplants.
•Iflightiscompletelyblockedfrombottomdwellingplants,theplantswillstop
producingoxygenandwilldie.Astheplantsaredecomposed,bacteriawill
useupevenmoreoxygenfromthewater.Lowdissolvedoxygencanleadto
fishkills.
•HighTSScanalsocauseanincreaseinsurfacewatertemperature,
becausethesuspendedparticlesabsorbheatfromsunlight.Thiscancause
dissolvedoxygenlevelstofallevenfurther(becausewarmerwaterscan
holdlessDO),andcanharmaquaticlifeinmanyotherways,

18. Physical Parameters
Turbidity
•Purewaterisclearanddonotabsorblight.
•Turbidityisthecloudinessofwater.Itisameasureoftheabilityoflightto
passthroughwater.
•Itiscausedbysuspendedmaterialsuchasclay,silt,organicmaterial,
plankton,andotherparticulatematerialsinwater
•Somematerialsthatgiveturbiditymaybetoxictoconsumers.Therefore
turbidwaterisnotsuitablefordrinkingpurposes.
•Turbiditypreventspenetrationoflightintodeeperlayerofnaturalwater
systemthatdirectlyaffectsphotosyntheticorganisminbottom.
•Drinkingwatershouldhaveturbiditylessthan5NTU(Naphthalometric
turbidityunit)

19. Physical Parameters
Turbidity
•Turbidityismeasuredbyaninstrumentcallednephelometricturbidimeter,
whichexpressesturbidityintermsofNTUorTU.
•Turbiditymorethan5NTUcanbevisibletotheaveragepersonwhile
turbidityinmuddywater,itexceeds100NTU.
•Groundwaternormallyhasverylowturbiditybecauseofthenaturalfiltration
thatoccursasthewaterpenetratesthroughthesoil

20. Physical Parameters
Temperature
•Itisoneoftheimportantparameterinnaturalsurfacewatersystem.
•Desirablelimitoftemperaturefordomesticuserangingbetween10
0
Cto
20
0
C.
•Thetemperatureinwatergovernsthekindsandtypesofaquaticlifethat
liveinit.
•Itregulatesthemaximumdissolvedoxygenconcentrationofthewater.
•Temperatureinfluencestherateofchemicalandbiologicalreactions.
•Itaffectsthedissolvedoxygenlevelinwater,photosynthesisofaquatic
plants,metabolicratesofaquaticorganisms,andthesensitivityofthese
organismstopollution,parasites,anddisease.

21. Chemical Parameters
1.Total Dissolved Solids (TDS)
2.pH
3.Acidity
4.Alkalinity
5.Hardness
6.Chlorides
7.Fluorides
8.Metals
9.Organic matter

22. Chemical Parameters
TDS :
•Organicandinorganicparticlesdissolvedinwater
•Sizesvariesfrom10
-3
µmto10
-5
µm
•Theymayimpartcolour,taste,toxicityandsmellinwater
•Canberemovedbyreverseosmosis,electrodialysis,etc.
pH :
•DefinedasthenegativelogarithmofH
+
ionconcentration
•Itismeasureofdegreeofacidityoralkalinityofwater
•MeasuredonpHscale,whichvariesfrom0to14.
•PotablewatershouldhavepHinrangeof6.5to8.5

23. Chemical Parameters
Acidity :
•CapacityofsubstancetoneutralizeOH
-
ions
•DuetopresenceofmineralsanddissolutionofCO
2
•Causesthecorrosionofmetalsandpipelines
Alkalinity :
•CapacityofsubstancetoneutralizeH
+
ions(acids)
•Duetopresenceofbicarbonates,carbonatesandhydroxides
•Itimpartsbittertastetowater

24. Chemical Parameters
Hardness :
•Definedasthesoapdestroyingpropertyofwater
•CarbonatesandbicarbonatesofCalciumandmagnesiumareresponsible
oftemporaryhardnesswhile,sulphates,chloridesandnitratesof
calciumandmagnesiumareresponsibleforpermanenthardness.
•Causesexcessiveconsumptionofsoapinlaundries
•Formsdepositsinboiler
•Groundwaterhavemorehardnessthansurfacewater

25. Chemical Parameters
Chlorides :
•Duetointrusionofseawater,industrialwastesanddomesticwastes
•UsuallypresentinformofCaCl,NaClandMgCl
•Impartssaltytasteinwater
Fluorides :
•Mainlyassociatedwithsomesedimentaryrocksandigneousrocks
•Harmfulandtoxicforhumanandotheranimalsifpresentedinlargequantity
whilesmallamountcanbebeneficial
•Itsdeficiencycancausedentalcavitiesinchildren
•Excessamountcancausediscolorationofteeth(Fluorosis)

26. Chemical Parameters
Metals :
•Addedtowaterbymining,industrialoragriculturalsources
•Arsenic,Cadmium,Chromium,leadandmercuryaresomeofthetoxic
metals
•ExcessamountofSodiumcausebittertasteandcausehealthhazardlike
cardiacandkidney
•IronandManganeseimpartcolourevenifpresentedinsmallquantity
Organic matter :
•UtilizedDOofwaterbodiesfortheirdegradationanddecreasedDOlevelwhich
affectstheaquaticecosystem

27. Biological Parameters
Thecombinedgroupofpathogenicandnon-pathogenic
bacteriaistermedasB-coligroup.
Bacteria -Cholera, diarrhea, typhoid, jaundice
Protozoa –Amebic dysentery, giardiasis
Viruses –Hepatitis, meningitis, poliomylitis

28. WATER POLLUTANTS
Oxygen demanding waste ( BOD, COD)
Nutrients ( Eutrophication)
Sediments ( Decreased photosynthesis, lower DO)
Toxic chemicals ( Bio accumulation, Biomagnification, BCF)
Pathogens ( Water borne diseases)
Radioactive materials ( highly harmful)
Thermal Pollutants ( Lower DO, increased biological actitivities, death of
heat sensitivity organisms)
VIDEO

29. EUTROPHICATION
VIDEO

30. EUTROPHICATION
1.Oligotrophic:
Water bodies with poor concentration of nutrients and very low
productivityof aquatic plants
2.Mesotrophic :
Water bodies with moderate concentration of nutrients and average
productivityof aquatic plants
3.Eutrophic :
Water bodies with very high concentration of nutrients and very high
productivity of aquatic plants

31. Control of Water Pollution
•Bypropersewagetreatment
•Propertreatmentofindustrialeffluents
•Judiciouslyusingpesticidesandchemicalfertilizers
•Encouragereuseofwater
•Bypreventingdischargesfromnuclearpowerplant
•Byprohibitingdirectwashingofclothesandanimalsinwater
bodiesusedfordrinkingwatersupply
•Reducingoilspills
•Increasingvegetationcovertoreducesoilerosion
•Publicawareness