Over 70% of the earth’s surface is covered by water and the rest is land. Most of this water is surface water, which occurs in form of dams, rivers, lakes, oceans and other surface water that can be seen. However some of the water is ground water, and most often we cannot see it but it contributes a lot to what we drink, and also replenishes our rivers and lakes and other surface sources (Goel 1). With the increasing world population which has hit a 7 billion mark, and the recent increasing industrialization around the globe, more pressure on the available water resources has been experienced (Calhoun 15). Naturally water is able to cleanse itself by either sedimentation, where foreign materials are allowed to sink to the bottom, or by diluting the contaminants to a level that is not harmful to living organism in water (Goel, 3). However this is only possible up to a certain level of dumping in water. Dumping of materials in any type of water is called water pollution.
Water pollution can be defined differently. According to Goel (4) it refers to release in water, energy and other materials that cause degradation of the quality of water. Generally the waste materials released into the water cannot be degraded naturally, and it accumulates to a level that is beyond the capacity of the river to cleanse it (Calhoun 7). Therefore the main characteristic of water pollution is accumulation of the polluting substance. For instance, if a small amount of ink is dumped in the ocean, it is diluted to a level that is not harmful to any living form in the water. The same ink, when discharged in massive amounts in the same water body, it changes the color of the water and in addition, the chemicals accumulate to toxic levels that can be fatal to the living things in the water.
According to Goel (6) Pollution of water can be determined by checking for the levels of various chemicals in water bodies, called chemical indicators. If the concentrations of these chemicals are high in the water such that they affect the users of the water, then the water is said to be contaminated. If the level of chemicals is low up to a certain permissible level, the water is said to be safe. Another way of knowing whether water pollution has taken place is to check for biological indicators. If a water body supports many life forms such as insects, fish, amphibians and others, then the water is said to be safe but if it supports none, is probably very badly polluted.
Sources of Water Pollution
Sources of water pollution are divided into two categories, point sources which include stationery locations such as sewage treatment plant, factories, septic systems and ships. All this clearly discharge waste substances into the water and can be traced (Calhoun 27).
Second category is non point sources. This are usually more difficult to trace their source and they includes fertilizers, chemicals, running off substances, landfill leaching, chemical and animal waste substances from farms, fields, mines and construction sites. According to the United States environmental protection agency, water pollution falls in six categories
a) Biodegradable wastes which include human and animal wastes add organic carbon to the water which provides a source of energy for aerobic bacteria in the water. The organic carbon is broken down to carbon dioxide and water. This can cause acidic rain and if the organic source is excess the aerobic bacterial can deplete all the oxygen in water causing all the other organisms in water to die.
b) Plants nutrients such as phosphates and nitrogen are added to water through runoffs of fertilizers, sewage and livestock waste. This causes the growth of algae in the water causing it to produce bad smell, become slimy and the water turns green and cloudy. This accelerates the rate eutrophication in water, which poses a threat to other life forms in water by depleting oxygen.
c) Heat pollutes water. High water temperatures reduce the oxygen levels of water. This heat can man made, for instance from cooling water in industrial discharges, or natural flow of water from hot springs to water bodies that are cooler. Fish and other life forms in the water bodies require certain levels of temperature and oxygen levels and this is altered then their survival is threatened. Therefore thermal pollution reduces the diversity of aquatic life.
d) Sediments consist of minerals and organic matter that are washed from land to the water body. It is a form of non point source and it causes many problems such as turbidity in water, clogging of smoother life forms and municipal sewer systems. Turbid water causes absorbs more solar radiation and therefore it adds to thermal pollution in water.
e) Human made toxic and hazardous chemicals such as oil, industrial discharges are a form of point sources and they cause water pollution. Oil spills in water bodies is particularly a major problem. It floats on water and causes oxygen absorption by water very difficult and also poses a danger to living organisms in sea. For example oil clogs the feathers of wings of birds making them unable to fly and also affects their food sources such as fish which die in large numbers.
Industrial discharges include pesticide runoffs and others. Domestic and personal use of chemicals adds greatly to water pollution. Use of dyes, paints, flush down toilets and household cleaners are major contributors. Increased use of pesticides has greatly contributed to water pollution.
f) Radioactive pollution encompasses discharges from industries, hospitals, and uranium mines into clean water bodies. Radioactive materials are capable of causing genetic mutations in any living organism and have been particularly linked as a major cause of cancer in humans. Such recent pollution was experienced in Japan after the country was hit by a tsunami, which destroyed several nuclear plants, which caused leakage of the radioactive materials to the water. Though the effects are yet to be felt, soon it will be evident. Radioactive materials can take very long to be depleted and can therefore cause harm in continuity. Radioactive pollutants can also originate from natural isotopes such as radon. Other causes includes pollution of water ny plastics and alien species.
Effects of water pollution
According to Goel (22), pollution of water bodies started with the industrial revolution and if industries are going to be maintained then pollution is not about to end. However pollution has very bad effects to the economies of various countries and the people themselves. For instance an oil spill that occurs in large water bodies causes many problems. The oil could wash to the coastline where people live and this affects their economic activities such as fishing, and other recreational activities such as swimming. This severely affects major economic boosters sectors such as tourism and devastates the ecosystem. The oil which does not get to its destination also hampers activities that are dependent on oil such as transport, thereby further hurting the economy.
Sewage discharges also cause major problems. When this water gets to points where humans and other organism consume it, it can cause ill health especially to human beings. Sewage water can also poison shellfish and those who consume such fish are at risk of getting fatally ill, from a disease called paralytic shellfish poisoning (Calhoun 71). Shell fish grows along the coastline and it is no longer caught along the shore since that art of the sea is highly contaminated by the sewage. Any type of pollution causes harm to the environment. The environment is part of us and therefore anything that harms the environment harms us too. It is therefore that water pollution should be eradicated, or minimized to levels that the water is able to cleanse itself.
Methods of reducing water pollution
Water pollution can be countered by a variety of ways. The supreme laws of the land can intervene in a variety of remedies such as education, legislative laws and economic guidelines on water pollution (Chris 2005). Regarding education, people should be educated on the effects of the pollution of the water bodies and when the population is infirmed, this will be a sure way of reducing pollution of our water bodies. It is said that information is power, and this will actually come in handy. Normally, people get illnesses from polluted water sources and if they are informed of this fact, then they will surely work to reduce the practice.
The government should also put in place legislative laws that govern the use of water bodies. However this is a major challenge since the rivers cross many countries and the larger oceans cuts across continents. Therefore if one country has tight laws preventing water pollution and another country with which it shares a water body has loose law n the sane, then the countries will suffer the same consequence of water pollution. To make this more meaningful, all countries that share water bodies should agree on a standard law that is to govern how the water body is used. Examples of such laws have been developed and they include the 1972 London (Dumping) Convention, the 1982 UN Convention on the Law of the Sea, and the MARPOL international convention for the prevention of pollution from ships (Chris 2005).
Regarding the economy the government should adopt the a popular principle called polluter pay principle which requires that those who pollutes the water bodies pays money for the cleanup. This means that for oil tankers they should have insurance covers for cleanups incase of oil spills in the ocean. Also for people using plastics it means that they would have to pay more in order to clean the mess they leave behind. For industries, the principle requires that their outflow pipes that dumps wastes into water be located upstream and the inlet pipes that they use to get water in to their industries be located downstream, so that if they release harmful wastes they be the first to use it (Chris 2005).
At a personal level, one can also contribute to stopping water pollution in a variety of ways. This includes minimizing the water that one uses so as to reduce the effluent that gets to the water bodies, making regular maintenance of vehicles that leaks fuel, using pesticides sparingly, using natural cleaners such as vinegar, borax and baking soda and using detergents that contains low level of phosphates.
These activities would greatly add to efforts that are being put forward to curb the habit of water pollution, and it is imperative that all of us be able to do something to make safe drinking water for all of us. According to Goel (27) water is life and it plays important roles in our lives. In fact, 75% of our body is composed of water. The body processes that maintain life are dependent on water. Water is the home of many living organisms. Water makes us clean. According to the bible, cleanliness is second to Godliness. Water makes plants grow and beatifies our environment. Water is essential for life. It is therefore our duty to conserve our water sources so as we can live.