Water pollution is degrading of its quality as a result of various physical, chemical or biological agents falling into rivers, streams, lakes, seas and oceans. Water pollution has many causes:
- Industrial wastewater containing inorganic and organic waste, often down to the river and the sea. Annually in water sources come thousands of chemicals, the effect on the environment is not known. Hundreds of these substances are new compounds. According to water pollution facts, although industrial wastes in many cases are pre-cleaned, they still contain toxic substances that are difficult to detect.
- Domestic waste water containing, for example, detergents, eventually into rivers and seas. Fertilizers, the soil washes away, fall into drains leading to the lakes and seas. All these factors lead to severe water pollution, particularly in closed basins, lakes, bays and fjords.
- Solid waste. If the water contains a large amount of suspended solids, they make it opaque to sunlight and thus impede the process of photosynthesis in the water basins as stated in water pollution facts. This in turn causes disruptions in supply in these basins. In addition, solid waste is causing siltation of rivers and navigable canals which leads to the need for frequent dredging.
- Toxicity of inorganic waste. Discharge of industrial wastewater into rivers and the sea leads to an increase in their concentrations of toxic heavy metal ions such as cadmium, mercury and lead. A significant portion is absorbed or adsorbed by certain substances, and it is sometimes called self-purification process. However, in closed basins heavy metals can reach dangerously high levels.
- Microbiological contamination. According to the International Labor Organization, 70% of the world’s population uses substandard water. This problem is particularly acute in developing countries. Approximately 90% of all rural residents consistently use for drinking and bathing with contaminated water. According to World Health Organization, 80% of diseases in the world are due to insufficient quality and unsanitary water. Because of this, there are diseases such as cholera, typhoid, malaria, parasitic cirrhosis (helminthes diseases), and leprosy. Diseases associated with unsanitary water on the globe affect about 500 million people.
- Oil spill:
Citing U.S water pollution facts, only the States alone each year are responsible for approximately 13 000 cases of oil spills. In sea water falls annually to 12 million tons of oil. In the UK annually poured into the sewer in excess of 1 million tons of used motor oil.
Oil spilled into the sea water, has many adverse effects on sea life. First of all, kill birds drowning, overheating in the sun or deprived of food. It reduces light penetration in closed bodies of water and can raise water temperature. This is particularly detrimental to organisms that exist only in a limited temperature range.
Recent facts about water pollution
As noted in the 2010 UN report, prepared for the forum, over 400 million people live in regions with serious water shortages (in 2050 their number may increase to 2 billion), hundreds of million people are deficient in safe supply of drinking water, 850 million are starving because of the lack of water for irrigation. More than 3.5 million people (mostly children) die from diseases originating and developing from pollution of drinking water each year, lack of sanitation and basic hygiene. In third-world territories, the share of diseases influenced by consuming water unfit for drinking and food preparation, have raised to 75% of cases.
Excessive water withdrawals from natural sources have led to serious consequences for the environment. Thus, in certain locations of the US and other countries, groundwater gets to be spent faster than collected, and their levels steadily decline. As a result, even large rivers (Colorado, USA, the Yellow River in China, etc.) are often dry and did not fall as before into the ocean.
Many experts are convinced that the world has entered an era of resource wars, the most important of which is water. Although it takes 70% of the earth’s surface, only 2.5% of this area falls on fresh water. Two-thirds of the Earth’s freshwater is concentrated in the ice, and almost all the rest is scattered in the soil or deposited in the deep aquifers and is not yet available. Filed by scientists, today we consume 54% of available surface water runoff, and by 2025 this figure will reach 70%.
The following water pollution facts are about amounts of its actual demand. Water consumption is growing every year (the world’s population is increasing annually by about 90 million). In addition, humanity produces large amounts of waste, contaminating drinking water supplies. The annual volume of waste the world is estimated at 1.5 thousand cubic kilometers, and 1 liter of waste water unfit to drink 8 liters of fresh water. According to forecasts, by mid-century, only 3-4 countries in the world will not experience an acute shortage of fresh water. And for the foreseeable future should not rely on the desalination of sea water (today it covers 0.2% of world demand), since these technologies are very energy intensive. Half the world’s desalination plants located in the Gulf countries, which have no shortage of funds and energy.
At the conclusion of the UN experts, the highest quality drinking water today in Finland, Canada and New Zealand, the lowest – in Belgium, Morocco and India. On its reserves per capita in the lead are Denmark (through Greenland), Iceland and French Guiana. This list does not include Russia, even in the top ten, so it looks like it’s time to revise our understanding of the inexhaustible riches in this area. Worst of all are provided with fresh water, Kuwait, Gaza Strip (Palestine) and the UAE. In developed countries, the most expensive water in Germany (nearly $ 2 per cubic meter), the cheapest – in Canada ($ 0.4).