water pollution water quality

8/3/2019 Water Pollution Water Quality

http://slidepdf.com/reader/full/water-pollution-water-quality 1/22

WATER POLLUTION AND

WATER QUALITY

PARAMETERS

Tayyab Ashfaq

Institute of environmental engineering &Research(IEER)

UET Lahore



WHAT IS WATER POLLUTION?

Any chemical, biological,

or physical change in

water quality that has a

harmful effect on living organisms or makes

water unsuitable for

desired usage.



WHAT ARE THE SOURCES OF WATER

POLLUTION? Point Sources

y Can be traced back to

one particular origin

Industrial Plants

(Power, Chemical, Waste

Treatment)

Drain pipes, Sewer

Lines, Underground

Mines

Nonpoint Sources

y Tend to be widespread

with many regions

contributing to the

water pollution.

Agricultural Runoff

Stormwater Runoff



POINT SOURCE OF POLLUTED W ATER



NONPOINT SOURCES

Buffer Zones Near Streams



POLLUTION OF L AKES

EutrophicationEutrophication

Fig. 22-7 p. 499



EUTROPHICATION OF L AKES

Eutrophication: nutrientenrichment of lakes mostlyfrom runoff of plantnutrients (nitrates and

phosphates)During hot dry weather

can lead to algae blooms

Decrease of

photosynthesisDying algae then drops

DO levels

Fish kills, bad odor



EUTROPHICATION IN L AKES

Solutions:

Advanced sewage treatment(N, P)

Household detergents

Soil conservation

Remove excess weed build up

Pump in oxygen or freshwater



Good 8²9

Water

Quality DO (ppm) at

20°C

Slightly

polluted6.7²8

Moderately

polluted 4.5²6.7

Heavily

polluted 4²4.5

Gravely

polluted Below

4



REDUCING SURFACE W ATER

POLLUTION

Nonpoint SourcesNonpoint Sources Point SourcesPoint Sources

Reduce runoff Reduce runoff

Buffer zone vegetation Buffer zone vegetation

Reduce soil erosion Reduce soil erosion

Clean Water Act Clean Water Act

Water Quality Act Water Quality Act

Only apply pesticides and fertilizers as need Only apply pesticides and fertilizers as need



DICHLORO DIPHENYL TRICHLOROETHANE

Very hydrophobic molecule which

acts by interfering with iontransport systems in neuronal cellmembrane

Inhibits neurotransmission killsanimals at certain dose

DDT (introduced in 1950s) is notspecies specific in its effects DDT and related insecticides,

endrin, dieldrin and aldrin are calledORGANOCHLORINE PESTICIDES

DDT revolutionised farmingpractices DDT was developed by Swiss

entomologist ² Paul MÜller Nobel Prize in 1948!

Banned in the mid-1960s in mostdevelo ed countries



MERCURY POISONING (MINAMATA BAY-1960)

POLYCHLORINATED BIPHENYL & PBB



Biomagnificati

ons of PCBs in

an aquatic foodchain from the

Great Lakes.



Category Example Sources

Causes health problems

Infectious agents Bacteria, virus, worms Human, animal waste

Organic chemicals Pesticide, plastic,detergents, oils

Industrial household farmuse

Inorganic chemicals Acids, caustic salts,

metals

Industrial effluent,

household cleaners, runoff Cause ecosystem disruption

Sediments Soil, silt Land erosion

Plant nutrients NO3,PO4,NH4 Agriculture fertilizers,

sewage, sludge

Oxygen demandingwastes

Animal human faeces,plant residues

Sewage, agriculturerunoff, paper millindustrial waste

Thermal Heat Power plant, cooling

water



W ATER POLLUTION CONTROL MEASURES

Pollution prevention approaches -Cleanertechnologies

´diverse range of products, services, and processesthat harness renewable materials and energy

sources, dramatically reduce the use of naturalresources, and cut or eliminate emissions andwastesµ

Good housekeeping-Water conservation

Oil grease traps Reuse/recover materials (Cr recovery, sewage

irrigation) Natural fertilizers Less pesticide(IPM)



W ATER POLLUTION CONTROL

Treat wastewater ²physical ,chemical, biologicaltreatments

Pollution control legislationy

Pakistan environmental quality act(1997)y National environmental quality standards(NEQS)

y Pollution charges

Enhance public awareness



CLEANER TECHNOLOGIES IN TANNING

INDUSTRY

Hide chilling to avoid salt in the effluent .

Hair recovery processes to reduce BOD/COD of the

effluent

Enzyme-assisted unhairing to reduce sulphide CO2 deliming to reduce ammonia in the effluent

Better uptake/exhaustion of chrome or chrome

recovery/recycling to reduce chrome in the effluent

Alternative mineral tanning agents to avoid chrome inthe effluent or solid wastes



W ATER QUALITY

Quality :degree of excellence,a measure of fitness of use Drinking water quality: degree of cleanliness and

wholesomeness of water

Physical

Chemical bacteriological



WHAT IS WATER POLLUTION?

WHO: 3.4 million premature

deaths each year fromwaterborne diseases

1.9 million from diarrhea

water pollution water quality

Documents