https://www.youtube.com/watch?v=IG3thzNUIdY

1. 11
WaterPollutionWaterPollution
Reference:Reference:
G. Tyler Miller’sG. Tyler Miller’s
Living in the EnvironmentLiving in the Environment
1414thth
EditionEdition
Prepared byPrepared by
AADITYA JAGAN INGALEAADITYA JAGAN INGALE

2. 2
Key ConceptsKey Concepts
 Types, sources, and effects of water pollutantsTypes, sources, and effects of water pollutants
 Major pollution problems of surface waterMajor pollution problems of surface water
 Major pollution problems of groundwaterMajor pollution problems of groundwater
 Reduction and prevention of water pollutionReduction and prevention of water pollution
 Drinking water qualityDrinking water quality

3. 3
Types, Effects, and Sources of WaterTypes, Effects, and Sources of Water
PollutionPollution
• Water is polluted byWater is polluted by infectious bacteriainfectious bacteria , inorganic, inorganic
and organicand organic chemicalschemicals, and, and excess heatexcess heat ..
• Water pollution is any chemical, biological, orWater pollution is any chemical, biological, or
physical change in water quality that has aphysical change in water quality that has a
harmful effect on living organisms.harmful effect on living organisms.
• The WHO estimates thatThe WHO estimates that 3.4 million people die3.4 million people die
prematurely each year from waterborne diseases.prematurely each year from waterborne diseases.
• In the U.S., an estimatedIn the U.S., an estimated 1.5 million people1.5 million people aa
year become ill from infectious agents.year become ill from infectious agents.

4. 4
• Scientists monitor water quality by usingScientists monitor water quality by using bacterialbacterial
counts, chemical analysis, and indicatorcounts, chemical analysis, and indicator
organismsorganisms..
• One method of measuring water quality involvesOne method of measuring water quality involves
measuring the number of colonies of fecalmeasuring the number of colonies of fecal coliformcoliform
bacteriabacteria present in a water sample.present in a water sample.
• Drinking water should not containDrinking water should not contain anyany
colonies/100colonies/100 milliliters,milliliters,
• Chemical analysisChemical analysis includes checking inorganicincludes checking inorganic
and organic chemicals present, sediment content,and organic chemicals present, sediment content,
and turbidity of water.and turbidity of water.
• Indicator speciesIndicator species are living organisms that areare living organisms that are
monitored to determine levels of pollution.monitored to determine levels of pollution.

5. 5
Sources of Water PollutionSources of Water Pollution
Point sources
Nonpoint sources
Water quality

6. 6
Point and Nonpoint SourcesPoint and Nonpoint Sources
NONPOINT SOURCES
Urban streets
Suburban
development
Wastewater
treatment
plant
Rural homes
Cropland
Factory
Animal feedlot
POINT
SOURCES

7. 7
Sources of water pollutionSources of water pollution
The leading sources of water pollution areThe leading sources of water pollution are
agriculture, industries, and mining.agriculture, industries, and mining.
1.1. Agricultural activitiesAgricultural activities are the leading cause ofare the leading cause of
water pollution from erosion, overgrazing,water pollution from erosion, overgrazing,
fertilizers and pesticides, and excess salt fromfertilizers and pesticides, and excess salt from
irrigated soils.irrigated soils.
2.2. Industrial facilitiesIndustrial facilities are another large source ofare another large source of
water pollution, and mining is a third source.water pollution, and mining is a third source.

8. 8
• One of every fiveOne of every five people in the world lackspeople in the world lacks
access to safe drinking water.access to safe drinking water.
• Ninety-five percentNinety-five percent of people in developedof people in developed
countries andcountries and 74%74% of people in developingof people in developing
countries have access to clean drinking water.countries have access to clean drinking water.
• In a warmer world, too much rain and too littleIn a warmer world, too much rain and too little
rain can increase water pollution.rain can increase water pollution.

9. 9
Pollution of Freshwater StreamsPollution of Freshwater Streams
StreamsStreams can recover from moderate levelscan recover from moderate levels ofof
degradable water pollutants if the flows are notdegradable water pollutants if the flows are not
reduced.reduced.
1.1. A combination ofA combination of dilution and biodegradationdilution and biodegradation
can allow recovery of stream pollutioncan allow recovery of stream pollution
2.2. The breakdown of pollutants by bacteria createsThe breakdown of pollutants by bacteria creates
anan oxygen sag curveoxygen sag curve . Organisms that have a. Organisms that have a
high oxygen demand can’t survive in the curve.high oxygen demand can’t survive in the curve.
3.3. Volume of the stream, volume of wastesVolume of the stream, volume of wastes
entering, flow rate, temperature, and pH levelsentering, flow rate, temperature, and pH levels
all affect how great a sag curve is produced.all affect how great a sag curve is produced.

10. 10
Oxygen Sag CurveOxygen Sag Curve

11. 11
Pollution of LakesPollution of Lakes

12. 12
Groundwater Pollution: CausesGroundwater Pollution: Causes
 Low flow ratesLow flow rates  Few bacteriaFew bacteria
 Cold temperaturesCold temperatures
Coal strip
mine runoff
Pumping
well
Waste lagoon
Accidental
spills
Groundwater
flow
Confined aquifer
Discharge
Leakage from faulty
casing
Hazardous waste injection well
Pesticides
Gasoline
station
Buried gasoline
and solvent tank
Sewer
Cesspool
septic tank
De-icing
road salt
Unconfined freshwater aquifer
Confined freshwater aquifer
Water pumping
well Landfill
 Low oxygenLow oxygen

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Ocean PollutionOcean Pollution
Fig. 22-11 p. 504

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Case Study: Chesapeake BayCase Study: Chesapeake Bay
 Largest USLargest US
estuaryestuary
 Relatively shallowRelatively shallow
 Slow “flushing”Slow “flushing”
action to Atlanticaction to Atlantic
 Major problems with dissolved OMajor problems with dissolved O22

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Oil SpillsOil Spills
Sources:Sources: offshore wells,offshore wells,
tankers, pipelines andtankers, pipelines and
storage tanksstorage tanks
Effects:Effects: death of organisms, lossdeath of organisms, loss
of animal insulation andof animal insulation and
buoyancy, smotheringbuoyancy, smothering
Significant economic impactsSignificant economic impacts
Mechanical cleanup methods: skimmers and blottersMechanical cleanup methods: skimmers and blotters
Chemical cleanup methods: coagulants and dispersingChemical cleanup methods: coagulants and dispersing
agentsagents

16. 16
Solutions: Preventing and ReducingSolutions: Preventing and Reducing
Surface Water PollutionSurface Water Pollution
Nonpoint SourcesNonpoint Sources Point SourcesPoint Sources
Reduce runoffReduce runoff
Buffer zone vegetationBuffer zone vegetation
Reduce soil erosionReduce soil erosion
Clean Water ActClean Water Act
Water Quality ActWater Quality Act

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Technological Approach: Septic SystemsTechnological Approach: Septic Systems
equire suitable soils and maintenanceequire suitable soils and maintenance

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Technological Approach:Technological Approach:
Advanced (Tertiary) SewageAdvanced (Tertiary) Sewage
TreatmentTreatment
Uses physical and chemical processesUses physical and chemical processes
Removes nitrate and phosphateRemoves nitrate and phosphate
ExpensiveExpensive
Not widely usedNot widely used

19. 19
Drinking Water QualityDrinking Water Quality
Safe Drinking Water ActSafe Drinking Water Act
Maximum contaminant levels (MCLs)Maximum contaminant levels (MCLs)
Purification of urban drinking waterPurification of urban drinking water
Bottled waterBottled water
Protection from terrorismProtection from terrorism
Purification of rural drinking waterPurification of rural drinking water