Water is a key resource for our quality of life.
It also provides natural habitats and eco-systems for plant and animal species.
Access to clean water for drinkingand sanitary purposes is a precondition for human health and well-being.
Clean unpolluted water is essential for our ecosystems.
Plants and animals inlakes, rivers and seas react to changes in their environment caused by changes in chemical water quality and physical disturbance of their habitat.
Water pollution is a human-induced change in the chemical, physical, biological, and radiological quality of water that is injurious to its existing, intended, or potential uses such as boating, waterskiing, swimming, the consumption of fish, and the health of aquatic organisms and ecosystems.
Thus, the discharge of toxic chemicals from a pipe or the release of livestock waste into a nearby water body is considered pollution.
The contamination of ground water, rivers, lakes, wetlands, estuaries, and oceans can threaten the health of humans and aquatic life.
Contaminants have a significant impact on aquatic ecosystems. for example, enrichment of water bodies with nutrients (principally nitrogen and phosphorus) can result in the growth of algae and other aquaticplants that shade or clog streams.
Direct exposures to toxic chemicals such as pesticides, is also a health concern for individual aquatic plants and animals.
Without healthy water for drinking, cooking, fishing, and farming, the human race would perish.
Clean water is also necessary for recreational interests such as swimming, boating, and water skiing
Sources of Water Pollution
Sources of water pollution are generally divided into two categories.
The first is point-source pollution, in which contaminants are discharged from a discrete location.
Sewage outfalls and oil spills are examples of point-source pollution.
The second category is non-point-source or diffuses pollution, referring to all of the other discharges that deliver contaminants to water bodies.Numerous manufacturing plants pour off undiluted corrosives, poisons, and other noxious by products to water streams.
The construction industry discharges slurries of gypsum, cement, abrasives, metals, and poisonous solvents.
The mining industry also presents persistent water pollution problems.
In yet another instance of pollution, hotwater discharged by factories andpower plants causes so-called 'thermal pollution' by increasing water temperatures.
Such increases change the level of oxygen dissolved in a body of water, thereby disrupting the water's ecological balance, killing off some plant and animal species while encouraging the overgrowth of others.
Towns and municipalities are also major sources of water pollution.
In many public water systems, pollution exceeds safe levels.
One reason for this is that much groundwater has been contaminated by wastes pumped underground for disposal or by seepage from surface water.
When contamination reaches underground water tables, it is difficult to correct and spreads over wide areas.
Discharge of untreated or only partially treated sewage into the waterways threatens the health of their own and neighboring populations as well.
Along with domestic wastes, sewage carries industrial contaminants and a growing tonnage of paper and plastic refuse.
Although thorough sewage treatment would destroy most disease causing bacteria, the problem of the spread of viruses and viral illness remains.
Additionally, most sewage treatment does not remove phosphorus compounds, contributed principally by detergents.
0 comments:
Post a Comment