Hydropower is also clean, and does not pollute the earth in any way. It prevents the burning of 22 billion gallons of oil or 120 million tons of coal each year.
History
Since the Industrial Revolution, pollution of all kinds has soared with an increase. All types of pollutions like air and water have been affected by the sudden use of machines. Back in the mid 18th century, England went on a rampage to produce ingenious inventions which have shaped our modern day life now.
But the effects of the coal burning, new cars and other inventions created a severe problem with the environment. Pollution from the smoke of the constantly burning coal affected the air, and the waste produced was often dumped into the water bodies.
Modern Day
Although there have been several attempts to clean our water system, water still falls victim to pollution. Every year, 14 billions pounds of sewage, sludge, and garbage are dumped into the world's oceans. 19 trillion gallons of waste also enter the water annually.
The graph below shows the distribution of pollution in one part of the world in 1999.
The Causes for Water Pollution
The biggest single water pollutant is sewage. Human waste is dumped into the earth’s water, and there are hardly any attempts to clean it up. But even if sewage was treated, the problem is still very severe.
Oil Spills
Sometimes, if you go down to the beach, and you move the top layer of the sand away, you will see that underneath, is a black substance. This black substance is oil.
The oil could have come from various places, but the most common way of the oil getting there, is oil from oil spills.
Oil spills have in the past and present received much media attention.
The Sea Express in 1996 released 72,000 tonnes of crude oil into Milford Haven in South Wales.
The Braer in 1993 split its 85,000 tonnes of crude oil into the water bodies of the Shetlands Islands.
Many more other spills before and after these have happened. I will talk of the Exxon Valdez in more detail.
The Exxon Valdez
The Exxon Valdez was one of the first of its kind to carry oil across oceans. It was a large vessel which could carry 1.48 million barrels of crude oil per voyage.
The Exxon Valdez struck Bligh Reef in Alaska on March 24th 1989, when oil started to leak out of its hull. After only three and a quarter hours, 5.8 million gallons of oil was released into the Prince William Sound. It was estimated that 11 million gallons of crude oil was finally released across the 1,300 miles of coastline.
The water became black and disabled or killed most animal life.
The initial clean up took three years to complete and an amazing $2.1 billion.
A technique used to clean the oil was by using oil booms. The picture to the left shows how it is done. The booms consisted of three boats. Two boats hauled the booms while the third rode at the top, collecting the oil from the surface of the water.
This technique proved a bit effective, but the oil patches kept moving, so it was not as efficient.
They also used pressure washing method. The oil affected the shorelines, and using high-pressure hoses, they were able to spray the oil away and pick it up after.
Chemical dispersants were not widely used though, as it was discovered that there was not enough wave motion to mix the oil and the water, so they discontinued their use. Chemical Dispersants are normally used though, with the help of wave motion to mix the oil and water together, so they can evaporate and ‘disperse’.
The animals also had to be cleaned. Birds and other wildlife could die, if they attempted to lick their fur or feathers in an attempt to cleanse themselves. The oil causes serious problems once digested. Fortunately, most of the wildlife that suffered in the oil spill has recovered, but some species still struggle to maintain their numbers after the disaster.
Farm waste, from animals and other farm products, are often getting into the water, and can be very poisonous.
Environmental workers are dispersing oil-eating chemicals into this water, which is loaded with oil. (Right)
Problems caused by pollution
The problems caused by the pollution are significant.
Sewage encourages the growth of toxic algae, which many primary consumers eat, and causes them to die. Sewage also produces bacteria, and with the algae, uses a lot of oxygen.
Animal waste in the water system can cause chemical reactions, which takes out the oxygen in the water, which life in the water needs to survive. Animal waste can be up to 100 times more polluting than domestic sewage.
Pollutants can kill dolphins, birds and fish which are contaminating their habitat and their bodies wind up on beaches.
Pollution can also affect human in a huge way too. Many people in the poorer countries of the world have not got the advantage of clean water, as we do. Their water is normally contaminated by germs, which could have been caused by pollution. Hundreds of people die each year from drinking this contaminated water.
What can we do to clean water pollution?
There are many things we can do to clean up our water, but the best way is to prevent it from happening in the first place. Unfortunately, there will sometimes be accidents that happen, which will create water pollution, but then we can help clean it up.
With oil, we can wait for it to naturally disperse, with help from the weather (such as waves and high winds) or we can do the various techniques mentions under the Exxon Valdez.
The government has also put more money in over the last couple of decades to improve the cleanness of the water.
What is being done to prevent water pollution?
In many countries, the dumping of waste and sewage is banned, but there are still several out there who have not taken up this ban yet.
The laws for agricultural pollution have changed. A water pollution offence can lead to a maximum fine of £20,000 in a magistrate’s court, or even more severe sentences in the higher courts.
Conclusion
I have learnt from doing this piece on water pollution the importance of water in our everyday life and the amount of pollution there is. Water pollution is still a major problem in many parts of the world, and I think there should be more done to help stop and prevent it from happening.
