The paper is devoted to the problem of pure drinking water.
Key words: drinking water, drinking water standards, underground waters.
Introduction.
Common knowledge, water is essential for human health:
1) over 60 % of the human body consists of water;
2) brain is over 70 % water;
3) 80 % by weight of blood is water.
Drinking water is water safe enough to be consumed by humans or used with low risk of direct or long period harm. In the most developed countries the tap water supplied to households, commerce and industry meets the water quality potability standards, even though only a very small proportion is actually consumed or used in food preparation [1].
Drinking water contains small amounts of bacteria. Most of these bacteria are generally not harmful. Chlorine is usually added to drinking water to prevent bacterial growth while the water streams through pipelines. This is why drinking water also contains minimal amounts of chlorine.
Today the problem of drinking water quality in many areas is one of the main global problems witch should be solved in the first place.
How is drinking water quality protected?
All countries have their own legal drinking water standards. The standards are set to be protective of public health and the definition of wholesome reflects the importance of ensuring that water quality is acceptable to consumers.
These prescribe which substances can be in drinking water and what the maximum amounts of these substances are. The standards are called maximum contaminant levels. They are formulated for any contaminant that may have adverse effects on human health and each company that prepares drinking water has to follow them up. If water will be purified to make it suitable to drink it will be tested for a number of dangerous pollutants, in order to establish the present concentrations. After that, one can determine how much of the contaminants have to be removed and if necessary purification steps can be progressed [2].
Globally, the most prevalent water quality problem is eutrophication (excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen), a result of high-nutrient loads (mainly phosphorus and nitrogen), which substantially impairs beneficial uses of water. Major nutrient sources include agricultural runoff, domestic sewage (also a source of microbial pollution), industrial effluents and atmospheric inputs from fossil fuel burning and bush fires.
Underground waters are the most protected from anthropogenic influence, but, despite it, water quality in areas of intensive water intake doesn’t adapt to drinking requirements [3].
The aim of this paper is to consider underground waters usage problems in Tomsk region.
Underground waters are used for supplying the population of Tomsk region with drinking water. The share of underground water in the balance of household and drinking water supply of Tomsk administrative districts is 90–92 %, and the surface waters are used only in Tomsk and Asinovsky districts, mainly for hot water supply and technical purposes [4].
The main part of the total water consumption is provided from surface sources for industry needs, especially of enterprises of chemical and petrochemical industries, and the maximum load rests upon the Tom River.
The main problems of the condition of water bodies in Tomsk region are:
1) The quality of drinking water and pollution of sources of drinking water supply.
2) Pollution of surface water bodies.
3) The condition of courses and banks of water bodies.
4) The marshiness of the territory of Tomsk region.
The surface waters in Tomsk region cannot be used for organization of centralized water supply owing to their vulnerability because of anthropogenic pollution. The rivers, at banks of which the largest residential areas are situated, are highly polluted as a result of repeated disposals of untreated sewage of industry, agricultural production, lumbering operation, oil and gas extraction industries.
Underground water is only reliable source of high-quality household and drinking water supply of the population of the Tomsk region. Underground water reserves are capable of meeting Tomsk Region citizens’ needs not only at present, but in long term as well.
At the same time, the quality of underground water in natural conditions by a number of such indices as contents of iron, manganese, in separate cases — of phenols, nitrogen-containing substances, oil products, and in some northern districts — water dissolved gases (hydrogen sulphide, methane), does not meet requirements of Sanitary Regulations and Standards. In bacteriological terms, the waters, as a rule, meet the existing requirements.
However special water treatment before drinking water supply is carried out only at large intake facilities. The water, as a rule, is primitive at smaller and most decentralized intake facilities, while there is no treatment at single development wells. In these cases the population uses untreated water for meeting their needs. At many operating water intake facilities the zones of sanitary protection are not established or not maintained. Out of 830 water use facilities only 378 (about 46 %) of them have licenses for underground water production, at other facilities the production is unlicensed, and consequently there is uncontrolled use of underground water resources there. An important problem is presence of a big number of self-pumping and abandoned wells, which are almost never eliminated [4].
Tomsk artesian water intake is one of Russia's largest engineering constructions of this type (it includes 198 wells, located on the 3 lines connected of more than 60 km qanat length, the water treatment station and water disinfection).
Water conditioning systems (water purification) Tomsk underground water intake includes a traditional iron removal process simplified method of aeration followed by filtration through a fast filters. For disinfection use chlorination.
Water conditioning systems (water purification) Tomsk underground water intake includes a traditional iron removal process and then filtering through fast filters. Chlorination is used for disinfection [5].
The quality of drinking water of the city of Tomsk, the efficiency of sewage treatment plants is 95 % [5].
However, there is poor water quality in settlements Stepanovka, Anikin, Basandayka, Loskutov, Timiryazevo, Dzerzhinsky, where local artesian wells, water treatment plants are not available. Iron removal stations only planned to implementation for the centralized water supply [5].
References:
1. Drinking water. From Wikipedia, the free encyclopedia // available at: http://webslinger81.appspot.com/en.wikipedia.org/wiki/Drinking_water
2. Water Treatment Solutions. Available at: http://www.lenntech.com/applications/drinking/faq/drinking-water-faq.htm.
3. Naymushina O. Drinking water supply of Tomsk (Western Siberia, Russia): Groundwater resources and quality // 14th SGEM GeoConference on Water Resources. Forest, Marine And Ocean Ecosystems, www.sgem.org, SGEM2014 Conference Proceedings, June 19–25, 2014, Vol. 1, 215–222 pp.
4. Investment portal of the Tomsk Region // Available at: http://www.investintomsk.com/tomskaya_oblast/prirodnye_resursy/
5. Nauchnye trudy «Regional'nye problemy kachestva vody i sohraneniya zdorov'ya naseleniya», vypusk 21, Lipeck, 2009, 346 s.