Deterioration of physical, chemical, biological characteristics of water through natural & anthropogenic activities to such an extent that it becomes harmful to human beings, plants &animals.
Source of water pollution:
- Point source
- Diffused source
Point sources are those which discharge pollutants from specific locations (pipeline, sewers) to water bodies& common sources are (i) industries (ii)sewage treatment plants (iii) landfills (iv)hazardous waste sites (v)oil storage tanks.
Non-point or diffused site – there are widely scattered & discharged pollutants over large areas. Ex:-
- Agricultural field
- Steam water urban street.
Types of Water Pollutants
On the basics of sources
- Industrial pollutants- Pollutant chlorides, sulphides, carbonate, nitrites retreats of heavy metals such as mercury, lead lime, arsenic etc.
- Agricultural pollutants- pesticides, insecticides, synthetic chemical compounds, plant remains.
- Urban pollutants– automobile exhaust, lime &chemical fertilizers used in lowers, chemical for urban sewage, house hold sew rope.
- Natural pollutant- volcanic dusts, sediments due to weathering, landslides debris, decayed organic matters.
On the basics of physical and chemical characteristics
- Physical pollutants- pollutant changing the physical characteristics- ex color, turbidity, sediments, oil, grease contact, dissolved solids.
- Chemical pollutant- chlorides, sulfides sulfates, carbonates, nitrates of heavy metals ,mercury ,leads, cadmium, pesticides, insecticides& other chemical compounds.
On the basis of degradation.
- Degradable pollutants- the pollution can be broken down by biological means.
- Non (bio) degradable pollutants- chemical pollutants & solid toxic substance .
General effect of water pollution
- Spreading the epidemics. Ex Chorale, Typhoid etc.
- Water contaminated by asbestos fiber causes lung cancer and stomach diseases.
- Death of aquatic organization.
- Decreases agricultural productivity.
- Kill soil micro organism.
- Increase alkalinity of Soil.
- Increase in concentration of inorganic & organic nutrients causes eutrophication. Leads to rapid growth of plant and animals beyond control.
- Due to oil leakage in sea water causes ecological disaster in littoral ecosystem due mass death of sea organism.
Water pollution Control Measures
- Water treatment plant in industry.
- Sewage treatment plant in urban body.
Causes of contamination of Ground water
- Industrial waste: hazardous effluents released from industries contains heavy metals, ion &organic &inorganic species .these contaminate ground water.
- Agricultural waste: excessive use of fertilizer, pesticides and insecticides add lot of chemical to ground water.
- Domestic waste: domestic wastes add to pathogenic organism, oxygen demanding organism (both chemicals and biological) & solids to ground water.
- Run off from urban areas: rapid urbanization releases a lot of effluents containing oils, greases, heavy metal, detergents &etc.
Effect on ecosystem
Effect on human being
- Polluted ground water helps in spreading of epidemics, chronic diseases like typhoid, dysentery, diarrhea &etc.
- Water contaminated with toxic metals like tig, pb, cd, cr, cu and cyanides causes stomach &skin disease.
- Polluted ground water contaminated with fibers (asbestos) causes fatal disease.
Effect on plants
- Polluted ground water disturbs plant metabolism severely and has adverse effect on ecosystem.
- Contaminated ground water acidity or alkalinity of soil.
- Decreases soil fertility by sculling back& microorganism.
- Severely damage crop productivity.