The water pollution

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Water pollution is a large set of adverse effects upon water bodies such as lakes, rivers, oceans, and groundwater caused by human activities. Although natural phenomena such as volcanoes, algae blooms, storms, and earthquakes also cause major changes in water quality and the ecological status of water, these are not deemed to be pollution. Water pollution has many causes and characteristics. Increases in nutrient loading may lead to eutrophication. Organic wastes such as sewage impose high oxygen demands on the receiving water leading to oxygen depletion with potentially severe impacts on the whole eco-system. Industries discharge a variety of pollutants in their wastewater including heavy metals, organic toxins, oils, nutrients, and solids. Discharges can also have thermal effects, especially those from power stations, and these too reduce the available oxygen. Silt-bearing runoff from many activities including construction sites, deforestation and agriculture can inhibit the penetration of sunlight through the water column, restricting photosynthesis and causing blanketing of the lake or river bed, in turn damaging ecological systems.

Pollutants in water include a wide spectrum of chemicals, pathogens, and physical chemistry or sensory changes. Many of the chemical substances are toxic. Pathogens can obviously produce waterborne diseases in either human or animal hosts. Alteration of water's physical chemistry include acidity, conductivity, temperature, and eutrophication. Eutrophication is the fertilisation of surface water by nutrients that were previously scarce. Even many of the municipal water supplies in developed countries can present health risks. Water pollution is a major problem in the global context. It has been suggested that it is the leading worldwide cause of deaths and diseases, and that it accounts for the deaths of more than 14,000 people daily.

Sources of water pollution

· geology of aquifers from which groundwater is abstracted.

· industrial discharge of chemical wastes and byproducts.

· discharge of poorly-treated or untreated sewage.

· surface runoff containing pesticides or fertilizers.

· slash and burn farming practice, which is often an element within shifting cultivation agricultural systems.

· surface runoff containing spilled petroleum products.

· surface runoff from construction sites, farms, or paved and other impervious surfaces e.g. silt.

· discharge of contaminated and/or heated water used for industrial processes.

· acid rain caused by industrial discharge of sulfur dioxide (by burning high-sulfur fossil fuels).

· excess nutrients added (eutrophication) by runoff containing detergents or fertilizers.

· underground storage tank leakage, leading to soil contamination, thence aquifer contamination.

Contaminants

Contaminants may include organic and inorganic substances.

Some organic water pollutants are:

· insecticides and herbicides, a huge range of organohalide and other chemicals;

· bacteria, often is from sewage or livestock operations;

· food processing waste, including pathogens

· tree and brush debris from logging operations

· VOCs (Volatile Organic Compounds, industrial solvents) from improper storage.

Some inorganic water pollutants include:

· heavy metals including acid mine drainage

· acidity caused by industrial discharges (especially sulfur dioxide from power plants)

· chemical waste as industrial by products

· fertilizers, in runoff from agriculture including nitrates and phosphates

· silt in surface runoff from construction sites, logging, slash and burn practices or land clearing sites

Water pollution in Belarus

There are more than 20 thou rivers and more than 10 thou lakes in the Republic of Belarus. The total length of the rivers within the catchment areas of the Black and Baltic seas constitutes 90,6 thou km. If we imagine all the rivers as one blue band it could engird our planet twice.

Major rivers in our country are:

· Berezina

· Dnieper

· West Dvina

· Neman

· Pripyat

· Sozh

The total water resources of the country amount to 56,2 km³ a year. Our largest lakes are: Naroch (80 km²) and Osveyskoye (52,8 km²).

All major rivers are transboundary. The Dnieper and West Dvina originate in Russia, flow through Belarus and roll their waters to the Ukraine and Latvia correspondingly. After having come from the Ukraine the Pripyat passes through Belarus and returns to the Ukraine. The West Bug flowing-in from the Ukraine serves a State border line between Belarus and Poland, while the Viliya and the Neman flow to Lithuania from Belarus.

Man-made water systems:

· Berezinskaya system connects the West Dvina River with the Dnieper

· Two connecting channels: the Dnieper-Bug one and Oginsky

· Vileisko-Minskaya water system that satisfies the needs in water of the capital city of the Republic

Water regime of the rivers in Belarus is determined by spring tide and freezing periods. Spring tide is the most important phase. The height of the tide over the normal (low-water) water stage on the major rivers amounts to 8,6 - 12,8 m, and on medium-size and small ones - about two times lower. The high water period on the rivers lasts 30 - 120 days. Spring tide on the rivers alternates with summer and autumn low water when water levels reach the lowest points. Rivers freeze for 80 - 140 days starting from the second decade of November. In severe winters some small rivers can freeze through for up to 4,5 months, while in mild winters rivers do not freeze up.

Daily consumption of drinking water per capita in Belarus grew from 184 liters in 1990 to 219 in 2002, while in Minsk City the average consumption of water of drinking quality per person exceeds 350 liters a day. This is considerably higher than the amounts of water consumption in the majority of countries in Western Europe (120-150 liters a day).

In terms of available water resources, Belarus is in relatively favorable conditions. There are 3,6 thou m³ of water per capita including 1,4 thou m³ of ground water. This is better than in an average European state and considerably more than in neighboring countries: Poland (2,2 thou m³ a year) and the Ukraine (1,0 thou m³ a year).

Natural water contamination

Water Contamination Index can give you an idea about the extent of chemical contamination of water. Water is considered clean and referred to the 1st class of water quality if WCI does not exceed 0,3. If WCI is lower than 1 water is considered to be relatively clean, up to 2,5 - moderately contaminated. If it is higher than 4, 6 and 10 water is defined as dirty, very dirty and extremely dirty.

Wastewater is one of the most important contamination source of open-air water objects. In 2003, the volume of wastewater was: insufficiently treated one - 15,1 mln m³, treated to standards - 872,4, conditionally clean - 255,7 mln m³. For comparison: in 1980 the discharge of insufficiently treated wastewater amounted to 313,0 mln m³. In 1980-2003 the capacities of wastewater treatement plants increased by almost two times. The bulk of wastewater (about 50%) is formed in the sphere of образуется в сфере housing and municipal services.

Water sites are continuously subject to the contamination by atmospheric precipitation. Local sources of atmospheric pollution by motor transport, power plants and industries are supplemented with transboundary pollution. Calculations show that the share of Poland in the precipitation in Belarus that contains nitrogen oxides constitutes 23,5%, that of Russia - 10,5%, Germany - 9,8%, Ukraine - 5,7%, Western European countries - 29,7%, Lithuania and Latvia - 3,8%.

The accident at the Chernobyl nuclear power station resulted in the radioactive contamination of soil and water. The concentration of radionuclids in circulating water reservoirs reduces every year, while in stagnant basins (e.g. lakes, ponds and water reservoirs) the accumulation of radionuclids takes place, particularly in the bottom sediments. The data of the radiation monitoring of water sites show that by today the situation on the rivers of the Dnieper-Sozh and Pripyat catchment areas has stabilized. The average annual concentration of ¹³⁷Cs during the observation period of 1987-2003 in major and medium-size rivers considerably reduced, e.g. in case of the Dnieper River - from 266 to 20 Bq/m³, and Sozh - 1566 to 30 Bq/m³.

The application of chemicalization means (e.g. lime and mineral fertilizers, microelements and pesticides) and non-litter manure also affect the conditions of top-soil and water. River water can be contaminated with biogenic elements (e.g. nitrogen and phosphorous).

Quality preservation of ground water remains a pressing problem. The application of fertilizers and poisonous chemicals in agriculture causes the increase of chlorides in ground water by 4-6 times if compared with the background concentrations, sulphates - 2-4 times, nitrates - 6-10 times. A part of the contamination is related to the fallout of radionuclids, but their concentration in ground water does not exceed the standard of 10 Bq/dm³ accepted in the Republic.

Clean water is a guaranty of health. Quire often excessive sanitary and hygienic chemical and microbiological values are identified in drinking water and water used by the population in cultural and domestic purposes.

Remember:

· you should not drink water from a river, lake or a different reservoir without its special cleaning;

· the best way to prepare water for drinking is to boil it. Microorganisms die at 100⁰ C;

· the use of filters for cleaning water can remove more than 90% of different admixtures from it.

Nitrogen compounds, organics, metal compounds, phenols, petro products and radionuclids are the most characteristic contaminants in water in Belarus. Regularly observed excessive values of total iron, copper and manganese are mainly conditioned by natural factors.

Rational water use

The Ministry of Natural Resources and Environmental Protection coordinate the development and implementation of water management and protection activities. Permits for special water use that regulate the amount of fresh water intake and wastewater discharges, as well as concentration of pollutants in wastewater discharged by industries, municipal and agricultural enterprises form a basis for the management of water resources.

The rates of the environmental tax increase for exceeding the limits of water intakes and discharges specified in the permits, and for the excessive concentrations of contaminants in wastewater by 10 times for the water intakes above the limit and by 15 times for the water discharges above the limit. Higher rates of the tax are applied in case of the excessive concentrations of contaminants. A fine is envisaged in case of an emergency discharge, which depends on the amount of the contaminant released into in the water object.

New technological solutions that increase the capacities of wastewater treatment plants are used when upgrading them. In 2005, the discharges of insufficiently treated wastewater are to be reduced by 50% if compared with the amount in 2000.

In 2004 alone, 344 wastewater treatment plants were brought in order, as well as 1167 water intakes and 4139 water well sanitary protection zones. More than 2452 hectares of forestland were planted within water protection zones and riversides and shore fronts of lakes, reservoirs and ponds.

The Republic of Belarus signed the following international conventions:

· Convention on Wetlands of International Importance, Especially as Wildlife Habitat (RAMSAR Convention)

· Convention on the Protection and Use of Transboundary Watercourses and International Lakes.

Priority objectives:

· to provide for the sustainability of water ecosystems and for the prevention of their contamination and depletion;

· to reduce water consumption at production facilities and in the housing sector;

· to develop and apply measures aimed at the protection of ground water;

· to improve economic mechanisms providing incentives for the rational water use.

Water quality observation

Monitoring of surface water is carried out by the Ministry of Natural Resources and Environmental Protection. It includes observations of the background composition of natural water, environmental conditions of water sites and registration of surface runoff. Observations of the hydro chemical composition of surface water are conducted at 83 water sites. Hydro chemical observations at 74 water sites are made in complex with operative hydro biological observations.

Ground water is monitored by RUE «Belgeologiya». Operative observations of ground water conditions are conducted at 1174 boreholes of the basic observation network.

Sanitary and hygienic conditions of water having physical contact with man and directly affecting his health are controlled by the bodies of the Ministry of Health.

Hydro chemical monitoring identifies the quantitative content of the elements of main chemical composition, biogenic substances and contaminants at the time of sampling. Hydro biological monitoring provides for an assessment of the conditions of water sites that was formed during a preceding period.

Drinking water must be harmless in its chemical composition and epidemiologically safe. If you have doubts about water quality you should contact the sanitary-epidemiological station of your district.

water contamination pollution river

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