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Monday, August 29, 2011

Water Pollution

Water Pollution

Water pollution occurs when a body of water is adversely affected due to the addition of large amounts of materials to the water. The sources of water pollution are categorized as being a point source or a non-source point of pollution. Point sources of pollution occur when the polluting substance is emitted directly into the waterway. A pipe spewing toxic chemicals directly into a river is an example. A non-point source occurs when there is runoff of pollutants into a waterway, for instance when fertilizer from a field is carried into a stream by surface runoff. 
 Types of Water Pollution
Toxic Substance -- A toxic substance is a chemical pollutant that is not a naturally occurring substance in aquatic ecosystems. The greatest contributors to toxic pollution are herbicides, pesticides and industrial compounds. 
Organic Substance -- Organic pollution occurs when an excess of organic matter, such as manure or sewage, enters the water. When organic matter increases in a pond, the number of decomposers will increase. These decomposers grow rapidly and use a great deal of oxygen during their growth. This leads to a depletion of oxygen as the decomposition process occurs. A lack of oxygen can kill aquatic organisms. As the aquatic organisms die, they are broken down by decomposers which leads to further depletion of the oxygen levels. 
A type of organic pollution can occur when inorganic pollutants such as nitrogen and phosphates accumulate in aquatic ecosystems. High levels of these nutrients cause an overgrowth of plants and algae. As the plants and algae die, they become organic material in the water. The enormous decay of this plant matter, in turn, lowers the oxygen level. The process of rapid plant growth followed by increased activity by decomposers and a depletion of the oxygen level is calledeutrophication.
Thermal Pollution -- Thermal pollution can occur when water is used as a coolant near a power or industrial plant and then is returned to the aquatic environment at a higher temperature than it was originally. Thermal pollution can lead to a decrease in the dissolved oxygen level in the water while also increasing the biological demand of aquatic organisms for oxygen. 
Ecological Pollution -- Ecological pollution takes place when chemical pollution, organic pollution or thermal pollution are caused by nature rather than by human activity. An example of ecological pollution would be an increased rate of siltation of a waterway after a landslide which would increase the amount of sediments in runoff water. Another example would be when a large animal, such as a deer, drowns in a flood and a large amount of organic material is added to the water as a result. Major geological events such as a volcano eruption might also be sources of ecological pollution. 
Specific Sources of Water Pollution 

  • Farms often use large amounts of herbicides and pesticides, both of which are toxic pollutants. These substances are particularly dangerous to life in rivers, streams and lakes, where toxic substances can build up over a period of time. 
  • Farms also frequently use large amounts of chemical fertilizers that are washed into the waterways and damage the water supply and the life within it. Fertilizers can increase the amounts of nitrates and phosphates in the water, which can lead to the process of eutrophication. 
  • Allowing livestock to graze near water sources often results in organic waste products being washed into the waterways. This sudden introduction of organic material increaces the amount of nitrogen in the water, and can also lead to eutrophication. 
  • Four hundred million tons of soil are carried by the Mississippi River to the Gulf of Mexico each year. A great deal of this siltation is due to runoff from the exposed soil of agricultural fields. Excessive amounts of sediment in waterways can block sunlight, preventing aquatic plants from photosynthesizing, and can suffocate fish by clogging their gills. 
  • Clearing of land can lead to erosion of soil into the river. 
  • Waste and sewage generated by industry can get into the water supply, introducing large organic pollutants into the ecosystem. 
  • Many industrial and power plants use rivers, streams and lakes to despose of waste heat. The resulting hot water can cause thermal pollution. Thermal pollution can have a disasterous effect on life in an aquatic ecosystem as temperature increaces decreace the amount of oxygen in the water, thereby reducing the number of animals that can survive there. 
  • Water can become contaminated with toxic or radioactive materials from industry, mine sites and abandoned hazardous waste sites. 
  • Acid precipitation is caused when the burning of fossil fuels emits sulfur dioxide into the atmosphere. The sulfur dioxide reacts with the water in the atmosphere, creating rainfall which contains sulfuric acid. As acid precipitation falls into lakes, streams and ponds it can lower the overall pH of the waterway, killing vital plant life, thereby affecting the whole food chain. It can also leach heavy metals from the soil into the water, killing fish and other aquatic organisms. Because of this, air pollution is potentially one of the most threatening forms of pollution to aquatic ecosystems.
  • Sewage generated by houses or runoff from septic tanks into nearby waterways, introduce organic pollutants that can cause eutrophication. 
  • Fertilizers, herbicides and pesticides used for lawn care can runoff and contaminate the waterway. As with agriculteral fertilizers, home fertilizers can lead to the eutrophication of lakes and rivers. 
  • Improper disposal of hazardous chemicals down the drain itroduce toxic materials into to the ecosystem, contaminating the water supplies in a way that can harm aquatic organisms.
  • Leaks of oil and antifreeze from a car on a driveway can be washed off by the rain into nearby waterways, polluting it. 

Water pollution FAQ Frequently Asked Questions

What is water pollution?

Water pollution is any chemical, physical or biological change in the quality of water that has a harmful effect on any living thing that drinks or uses or lives (in) it. When humans drink polluted water it often has serious effects on their health. Water pollution can also make water unsuited for the desired use.
What are the major water pollutants?There are several classes of water pollutants. The first are disease-causing agents. These are bacteria, viruses, protozoa and parasitic worms that enter sewage systems and untreated waste.
A second category of water pollutants is oxygen-demanding wastes; wastes that can be decomposed by oxygen-requiring bacteria. When large populations of decomposing bacteria are converting these wastes it can deplete oxygen levels in the water. This causes other organisms in the water, such as fish, to die.
A third class of water pollutants is water-soluble inorganic pollutants, such as acids, salts and toxic metals. Large quantities of these compounds will make water unfit to drink and will cause the death of aquatic life.
Another class of water pollutants are nutrients; they are water-soluble nitrates and phosphates that cause excessive growth of algae and other water plants, which deplete the water's oxygen supply. This kills fish and, when found in drinking water, can kill young children.
Water can also be polluted by a number of organic compounds such as oil, plastics and pesticides, which are harmful to humans and all plants and animals in the water.
A very dangerous category is suspended sediment, because it causes depletion in the water's light absorption and the particles spread dangerous compounds such as pesticides through the water.
Finally, water-soluble radioactive compounds can cause cancer, birth defects and genetic damage and are thus very dangerous water pollutants.
More information on health effects of microrganisms

Where does water pollution come from?Water pollution is usually caused by human activities. Different human sources add to the pollution of water. There are two sorts of sources, point and nonpoint sources. Point sources discharge pollutants at specific locations through pipelines or sewers into the surface water. Nonpoint sources are sources that cannot be traced to a single site of discharge.
Examples of point sources are: factories, sewage treatment plants, underground mines, oil wells, oil tankers and agriculture.
Examples of nonpoint sources are: acid deposition from the air, traffic, pollutants that are spread through rivers and pollutants that enter the water through groundwater.
Nonpoint pollution is hard to control because the perpetrators cannot be traced.

How do we detect water pollution?

Water pollution is detected in laboratories, where small samples of water are analysed for different contaminants. Living organisms such as fish can also be used for the detection of water pollution. Changes in their behaviour or growth show us, that the water they live in is polluted. Specific properties of these organisms can give information on the sort of pollution in their environment. Laboratories also use computer models to determine what dangers there can be in certain waters. They import the data they own on the water into the computer, and the computer then determines if the water has any impurities.

What is heat pollution, what causes it and what are the dangers?

In most manufacturing processes a lot of heat originates that must be released into the environment, because it is waste heat. The cheapest way to do this is to withdraw nearby surface water, pass it through the plant, and return the heated water to the body of surface water. The heat that is released in the water has negative effects on all life in the receiving surface water. This is the kind of pollution that is commonly known as heat pollution or thermal pollution.
The warmer water decreases the solubility of oxygen in the water and it also causes water organisms to breathe faster. Many water organisms will then die from oxygen shortages, or they become more susceptible to diseases.
For more information about this, you can take a look at thermal pollution.

What is eutrophication, what causes it and what are the dangers?

Eutrophication means natural nutrient enrichment of streams and lakes. The enrichment is often increased by human activities, such as agriculture (manure addition). Over time, lakes then become eutrophic due to an increase in nutrients.
Eutrophication is mainly caused by an increase in nitrate and phosphate levels and has a negative influence on water life. This is because, due to the enrichment, water plants such as algae will grow extensively. As a result the water will absorb less light and certain aerobic bacteria will become more active. These bacteria deplete oxygen levels even further, so that only anaerobic bacteria can be active. This makes life in the water impossible for fish and other organisms.

What is acid rain and how does it develop?

Typical rainwater has a pH of about 5 to 6. This means that it is naturally a neutral, slightly acidic liquid. During precipitation rainwater dissolves gasses such as carbon dioxide and oxygen. The industry now emits great amounts of acidifying gasses, such as sulphuric oxides and carbon monoxide. These gasses also dissolve in rainwater. This causes a change in pH of the precipitation – the pH of rain will fall to a value of or below 4. When a substance has a pH of below 6.5, it is acid. The lower the pH, the more acid the substance is. That is why rain with a lower pH, due to dissolved industrial emissions, is called acid rain.

Why does water sometimes smell like rotten eggs?

When water is enriched with nutrients, eventually anaerobic bacteria, which do not need oxygen to practice their functions, will become highly active. These bacteria produce certain gasses during their activities. One of these gases is hydrogen sulphide. This compounds smells like rotten eggs. When water smells like rotten eggs we can conclude that there is hydrogenpresent, due to a shortage of oxygen in the specific water.

What causes white deposit on showers and bathroom walls?

Water contains many compounds. A few of these compounds are calcium and carbonate. Carbonate works as a buffer in water and is thus a very important component.
When calcium reacts with carbonate a solid substance is formed, that is called lime. This lime is what causes the white deposit on showers and bathroom walls and is commonly known as lime deposit. It can be removed by using a specially suited cleaning agent.

What is Storm Water Pollution?

Any toxic discharge that enters into the storm water sewer system , as storm water flows (or snow melts), it picks up debris, chemicals - such as fertilizers and pesticides - dirt, cigarette butts and other pollutants . This discharge enters a storm sewer system and is discharged to a lake, stream, river, wetland, or coastal water.

The effects of water pollution

The effects of water pollution are varied and depend on what chemicals are dumped and in what locations.
Boston Harbor is a strong example of how badly pollution can damage bodies of water.  The water is filled with toxic waste and sewage, and routinely receives more waste when rainfall pushes it into the harbor.
Many bodies of water near urban areas are highly polluted.  This is the result of both garbage dumped by individuals and dangerous chemicals legally or illegally dumped by industries.
The main problem caused by water pollution is that it kills life that inhabits water-based ecosystems.  Dead fish, birds, dolphins, and many other animals often wind up on beaches, killed by pollutants in their habitat.
Pollution disrupts the natural food chain as well.  Pollutants such as lead and cadmium are eaten by tiny animals.  Later, these animals are consumed by fish and shellfish, and the food chain continues to be disrupted at all higher levels.
Eventually, humans are affected by this process as well.  People can get diseases such as hepatitis by eating seafood that has been poisoned.

Ecosystems can be severely changed or destroyed by water pollution.  Many areas are now being affected by careless human pollution, and this pollution is coming back to hurt humans.

how to save water pollution

Water Pollution Solutions

Today, water pollution is one of the serious concerns for each and every country around the world. Thus, for this purpose there are numerous of laws and regulations for water pollution solutions are been imposed everywhere. But, then also drawbacks are faced by these solutions to water pollution. Reason behind the drawbacks for water pollution solutions in India is not by its imposition but in some regions enforcement of these rules are not that much strict in comparisons to others.
To get control and to impose these water pollution solutions literally in every places, government just have to again place the regulations and rules regarding it. Moreover some effective water pollution solutions in India involves the reduction in manures and chemical usages and promoting a bio-dynamic cultivation for farming purposes. Lesser deforestation and creating ponds to lower the level of flow which enters under the surface as underground water are also major water pollution solutions. In another possible solutions to water pollution is to lower the level of usage for chemicals and other pesticides for farming process. By utilizing lesser or stopping gradually the usage of fertilizers and such chemicals also can be considered as very effective water pollution solutions in India. Some other solutions to water pollution are like, re-establishment of wetlands and filtration of waste materials. Driving fewer vehicles also results as better water pollution solutions. Better sewage and reduction of other dumping waste materials in seas and oceans also acts as solutions to water pollution. Conservation of water and better techniques for the managing the storm water are also good water pollution solutions in India.
Changes for water pollution solutions in India not only can take place on the national level but, individuals can contribute a lot in it. Any single person can also help in solutions to water pollution. By purchasing green products like organic products and individual protections for usage of chemicals in our daily life can also results in better water pollution solutions. It is a duty of every citizen to properly place the garbage and dispose off it to a right place which can reduce the unwanted chemical flow in the atmosphere and also reduces the waste materials which are dumped in seas and oceans.
Many laws have been created to restrict industries from dumping materials into the water.  However, many laws remain weak, and many countries do not restrict water pollution.
In the United States, the Clean Water Act was written to completely put an end to all dumping of pollutants into water.  The law has not been that effective in many areas, but in other locations, it has achieved its goals.
Since the Clean Water Act, other legislation has been enacted as well.  Now, eleven different federal government agencies and 21 federal government programs all monitor the quality of water and regulate pollution.
The world has spent tremendous sums of money trying to clean up water.  From 1972-1990, the US spent over $250 billion.
Many non-governmental projects are also being carry out in an effort to clean up the water.  Industries are beginning to reduce the amount of chemicals they dump into water, and environmental groups are participating in cleanup projects.
The plastics industry, blamed for some of the worst pollution of the water, is making its products degradable.  However, many environmentalists think this is hardly enough.
Public reaction to the water pollution problem has also been influential.  Governments have responded when public anger has risen, such as after theExxon Valdez accident.

Reduce Storm <b>Water Pollution</b>

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