Water pollution occurs when foreign substances alter the physical, chemical, or biological properties of water. This makes the water a health hazard and decreases its usefulness. Sources of water pollution include sewage, industrial effluents, agricultural runoff, pathogens, toxic elements, radioactive pollutants, and thermal pollutants. Contaminated water can cause health issues like infectious diseases as well as making water unpleasant to drink or use for food processing. Standards and treatment methods are needed to ensure water quality.

1. “ Any alteration in the physical or chemical or biological
properties of water and the contamination with any
unwanted foreign substances, which would contribute a
health hazard or otherwise decrease the utility of water”

2. Rain Water
Ground Water
Well, Springs, etc.
Surface Water
Sea, Ocean, River, Pond, Lake, etc.

3. Domestic Sewage
Industrial Effluents
Run off from land and fields
Pathogens
Agricultural Discharge
Oil
Toxic Elements
Radioactive Pollutants
Thermal Pollutants

4. Objectionable color and odour is unacceptable and
unsuitable for drinking and other purposes.
Highly turbid and very hard water is unpleasant to
drink, food processing
Acid and alkaline water cause serious health problem
Water borne infectious enteric disease like
typhoid, cholera, dysentery, are the predominant health
hazard arising from drinking contaminated water
Radioactive pollution enter human body through food
and get accumulated in thyroid gland, liver, bones and
muscles

5. Biodegradable waster deplete D O in the receiving
stream, affect the flora cause creates anaerobic
conditions
Non biodegradable waste and pesticides travel the food
chain and ultimately reach human where they
accumulate in fatty tissues
Thermal discharge in stream depletes D O
Phosphate, nitrate, promote the growth of algae and
encourage eutrophication
Industrial effluents result in addition of poisonous
chemicals such as arsenic, mercury, lead may reach human
body through contaminated food.

6. Lay down standard for
Drinking water
Disposal of waste water into water course/sewer/land
Monitoring
Government laws
Treatment
Domestic treatment
Screening
Sedimentation
Filtration, pH adjustment
Disinfection

7. Waste water treatment
Preliminary treatment
Primary treatment
Secondary treatment
Advanced treatment