1. SNS COLLEGE OF ENGINEERING
SESSION – 4
WATER POLLUTION

2. Water resources
The water cycle, through evaporation and precipitation, maintains hydrological systems which form rivers and lakes and support in a variety of aquatic ecosystems.
a large number of people for their daily needs such as drinking water, washing, cooking, watering animals, and irrigating fields.

3. Our liquid planet glows like a soft blue sapphire in the hard-edged darkness of space. There is nothing else like it in the solar system. It is because of water. – John Todd

4. Water availability on the planet
Water that is found in streams, rivers, lakes, wetlands and artificial reservoirs is called surface water.
Water that percolates into the ground and fills the pores in soil and rock is called groundwater.
Porous water-saturated layers of sand, gravel or bedrock through which ground water flows are called aquifers

5. Water Pollution
When the quality or composition of water changes directly or indirectly as a result of man’s activities such that it becomes unfit for any purpose it is said to be polluted.
Any pollutant that is discharged onto the land above, is also pulled into the aquifer and pollutes the groundwater resulting in polluted water in the nearby wells.

6. Point Vs Non- point sources of pollution
When a source of pollution can be readily identified because it has a definite source and place where it enters the water it is said to come from a point source. Eg. Municipal and Industrial Discharge Pipes.
When a source of pollution cannot be readily identified, such as agricultural runoff, acid rain, etc, they are said to be non-point sources of pollution.

8. Answer if possible
A little girl kicks a soccer ball. It goes 10 feet and comes back to her. How is this possible?
A is the father of B. But B is not the son of A. How’s that possible?
A 10 foot rope ladder hangs over the side of a boat with the bottom rung on the surface of the water. The rungs are one foot apart, and the tide goes up at the rate of 6 inches per hour. How long will it be until three rungs are covered?
An electric train is moving north at 100mph and a wind is blowing to the west at 10mph. Which way does the smoke blow?

9. Causes of water pollution
Disease-causing agents (pathogens)
Oxygen depleting wastes – Organic wastes (The amount of oxygen required to break down a certain amount of organic matter is called the biological oxygen demand (BOD))
Inorganic plant nutrients (The excessive growth of algae and aquatic plants due to added nutrients is called eutrophication)
Water soluble inorganic chemicals which are acids, salts and compounds of toxic metals such as mercury and lead
organic chemicals, which include oil, gasoline, plastics, pesticides, cleaning solvents, detergent and many other chemicals.

10. Sediment of suspended matter is another class of water pollutants (reduces photosynthesis)
Water soluble radioactive isotopes - various tissues and organs as they pass through food chains and food webs- cause birth defects, cancer and genetic damage
Thermal pollution – Hot water
Oil is washed into surface water in runoff from roads and parking lots which also pollutes groundwater

11. Groundwater pollution
Urban run-off of untreated or poorly treated waste water and garbage
Industrial waste storage located above or near aquifers
Agricultural practices such as the application of large amounts of fertilizers and pesticides, animal feeding operations, etc. in the rural sector
Leakage from underground storage tanks containing gasoline and other hazardous substances
Leakage from landfills
Poorly designed and inadequately maintained septic tanks
Mining wastes

12. Control measures
Setting up effluent treatment plants and treating waste
treated effluent can be reused for either gardening or cooling purposes
THERMAX

13. THERMAX
running contaminated water through the root zones of specially designed reed beds
REEDS- wetland plants have the capacity to absorb oxygen from the surrounding air through their stomatal openings
oxygen is pushed through the porous stem of the reeds into the hollow roots -enters the root zone , creates conditions suitable for the growth of numerous bacteria and fungi
micro-organisms oxidize impurities in the wastewaters, so that the water which finally comes out is clean

15. SUMMARY
1)Discharged pollutants at specific location through pipes, ditches or Sewers into bodies of surface water is ___________ 2) wetland plants have the capacity to absorb oxygen from the surrounding are _______ 3)Hot water is added by ________ pollution 4) When the ___________of water changes directly or indirectly such that it becomes unfit for any purpose it is said to be polluted 5) The amount of oxygen required to break down a certain amount of organic matter is called _________

16. Thank You