Point Sources of Water Pollution
Point sources are those from where the pollutants seep directly into the main water bodies. Since pollution takes place from a particular identifiable source, it's termed as point source. Since the source is discreet, the load of contaminants is also high.
Other types of conveyances that cause water pollution include ditches and running canals where wastes are deposited from municipalities or localities. The waste substances from factories and plants are directly thrown into oceans and seas, that pollute water to a large extent.
Such wastes are composed of various inorganic and organic substances that increase mineral load of water bodies causing depletion in number of decomposer microorganisms.
When the water used for cooling systems in factories is released directly into water bodies, thermal pollution takes place. The heat of water threatens aquatic life as the amount of dissolved oxygen in water substantially reduces. Radioactive materials when accumulated in water, cause serious health hazards to marine biota.
Non-Point Sources of Water Pollution
Non point sources are those that do not have a single point of origin. For example, when rainwater runs off land, it carries different types of contaminants along with, which mix with other water bodies. Thus, the contaminants accumulate from different sources, by which they cause water pollution.
The running water is highly polluted because it flows through roads, fields and waste water canals, that further merges with large water bodies. Thus, you can see that non-point sources have far flung effects. Such a source of water pollution is also known as urban runoff.
It also poses serious health risks to human beings when they unknowingly use the water for cooking purposes. This type of water pollution is more prevalent in villages.
● Wastes like plastic, anti-freeze chemicals, vegetable wastes, detergent wastes, etc., are more frequently disposed off from households. Such waste matters are often thrown into nearby canals and ponds.
All these activities are common sources of non-point water pollution that must be taken care of. Oil spills from ships is also rampant in oceans , where marine life is severely threatened. Ground water pollution takes place when contaminated rainwater seeps underground.
Controlling water pollution is an important global concern which is possible only through individual effort. Now that you know how water gets polluted you can stop those activities that contaminate water. Although it's not an overnight affair, we can still conscientiously make a move to preserve the water bodies from getting polluted.