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WATER QUALITY AND HEALTH ALBANIAN CASE Tania Floqi Polytechnic University of Tirana Vrnjacka Banja, 10.10.2007.

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Presentation on theme: "WATER QUALITY AND HEALTH ALBANIAN CASE Tania Floqi Polytechnic University of Tirana Vrnjacka Banja, 10.10.2007."— Presentation transcript:

1 WATER QUALITY AND HEALTH ALBANIAN CASE Tania Floqi Polytechnic University of Tirana Vrnjacka Banja,

2 Importance of water quality Drinking water supply in Albania Water supply in Tirana Tirana’s water quality - Physical characteristics - Chemical characteristics - Microbiological characteristic - Disinfection process - Health risks Conclusions and Recommendations

3 Importance of water quality Water is one of the most important chemicals known to men Rain, snow, sleet, hail, fog and dew - water present in the air Water is present on the earth surface as lakes, streams, wetlands, waterfalls and glaciers The human body is composed of 50 % water Water is important as a solvent. Many substances dissolve in water – sugar, salt, alcohol, etc. Access to safe drinking-water is important as a health and development issue at a national, regional and local level Water supply must be available to all

4 Drinking water supply in Albania Albania is a small mountainous country (28748 km2). It has a rich hydrographic net (groundwater, streams, rivers, springs, lakes, wetlands). This net includes over 200 big natural resources of flowing groundwater. Natural water qualities of our country are generally good

5 Drinking water origin - 80 % of – groundwater - 20 % - surface waters Population supply - 85% – By public system (Urban areas – at home; Rural areas – public taps and standpipes) - 10% – private wells - 4.9% – treated surface water - 0.1% – untreated surface water Drinking water supply in Albania

6 Quantity 20 – 50 lit/person/day at the taps 120 lit/person/day at the source 50-70% of the quantity is lost in the distribution system - Obsolete & old infrastructure - Poor maintenance & mismanagement Drinking water supply in Albania

7 Water supply in Tirana Tirana region has a wide variety of natural geological conditions that influence water quality Tirana city takes water from - surface water (Bovilla dam- reservoir) - flowing underground sources - artesian pumped wells All the above sources are different regarding physical, chemical and microbiological characteristics

8 Tirana’s water quality Physical characteristics Turbidity - usually in normal parameters - In rainy periods & damaged supply network ranges from 8 – 92 ntu Odor & Taste - usually in normal parameters - faecal odors & oil odors in rainy periods and damaged supply network - odors from algae (Cyklotela diatomea) occurs since 2 years ago in Bovilla reservoir - from these period began the monitoring of human activites impact such as biological, physical and chemical indicators Temperature – of Tirana’s water sources ranges from 7 -17º C depending from the type of source

9 Chemical characteristics Fluoride – low levels Arsenic, mercury and lead – not present Nitrates – varies from mg/l in Bovilla reservoir and pumped wells in the lowlands Nitrates in natural groundwater in mountainous areas are not present Pesticides and herbicides – not present in Bovilla reservoir; analyzed since one year ago Organic Matter – present in all water sources but not monitored because the lack of facilities Tirana’s water quality

10 Chemical characteristics Ammonia nitrogen - present in Bovilla reservoir, pumped wells and the distribution supply network Ammonia nitrogen is monitored as chemical indicator of sanitary pollution In pollution cases the ammonia level can reach 16 mg/l

11 Chemical characteristics Total Dissolved Solids (TDS) – varies from mg/l to mg/l - Water from pumped wells has higher TDS than natural surface or groundwater Conductivity - from 208 µmhos/cm to 944 µmhos/cm – related with TDS concentration Hardness ranges: - natural groundwater, 71 – 79 mg/l CaCO3 - pumped wells, 210 – 275 mg/l CaCO3 Hardness is dependent from natural geological conditions pH – varies from 6.96 to 7.85, don’t present carbonate alkalinity

12 Tirana’s water quality Microbiological characteristics Tirana’s water supply system is monitored by specialists from the Directorate of Public Health and from the City Water Supply and Sewerage Enterprise itself The monitored indicators are E.Coli, Streptococcus Faecalis and Total Coliforms

13 Tirana’s water quality Disinfection process Primary disinfectant used in Bovilla treatment plant – sodium hypochlorite (NaOCl) Secondary disinfectant used in distribution depots – sodium hypochlorite (NaOCl) The chlorination process is made manually by operators often not very qualified and responsible, affecting the level of chlorine which varies from very high to very low values

14 Health risks If feacal contamination is recent it is responsible for the presence of pathogenic agents including bacteria, viruses, protozoa, which may cause diseases from gastroenteritis to sometimes fatal diarrhea, dysentery, hepatitis, typhoid fever or cholera There was a cholera outbreak in 1994, in Albania, with 626 infected cases and 25 dead people Data from the Institute of Public Health indicate that there is a high incidence of gastroenteritis in Albania - the conclusions of health experts indicate that in most of cases the gastroenteritis is coming from drinking water pollution

15 Health risks In 2006 in Tirana, there was a critic situation of the hepatitis B disease, because of the contamination of distribution supply system The Ministry of Health (National Sanitary Inspectorate) decided to increase the quantity of disinfectant in the distribution system so the residual chlorine should be from 0.3 – 0.5 mg/l (national standard) to 1 mg/l

16 Tirana’s water quality Disinfection by-products – THM NOM can cause various interferences in water treatment such as: - React with chemical disinfectant (chlorine) to form disinfection by-products such as trihalomethanes. Trihalomethanes are suspected to be mutagenic, carcinogenic and/or teratogenic THM (18 compounds) are monitored since one year ago and are all in low levels

17 Conclusions The quality of drinking water in Tirana is strongly linked to the type of sources used to supply the population. Tirana is supplied with drinking water from surface, underground sources and artesian pumped wells. Each of these sources has different microbiological, physical, chemical and acceptability characteristics. Hardness can be classified as very hard (above 20 German degrees) for the waters in lowland regions and as soft for the natural groundwater in mountainous areas The quality of drinking water in Tirana has been deteriorating in the last years. There are more and more cases with microbial contamination, mainly with feacal origin. Main reason of this is the continuing amortization of both; drinking supply system and sewerage system. Summer months are the most common in regard to microbial contamination. Also, heavy rainfalls have shown to affect considerably the microbial quality of drinking water. The critical situation of the sewerage system creates a constant risk for the population health, depending mainly on infiltrations and out-spills in these specific days. Analyses have shown that the chemical indicator of water sanitary pollution (NH4+) is in accordance with bacteriological indicators. In many cases the presence of NH4+ is much higher than the allowed levels, going up to mg/l. The disinfection process is not consequent and analyses show that the level of chlorine is very variable in time and in different places of the supply network. Despite the bad technical conditions, the lack of experience and knowledge of the workers dealing with the chlorination process are main causes that affect negatively the distribution of chlorine in the distribution network. Analyses have shown that the chlorine concentration in the network is in an oblique correlation with the bacteriological (E. coli, Str. faecalis, Coliform Total) and chemical (NH4+) indicators. Nevertheless there are cases when the concentration of chemical and bacteriological indicators is in such high levels that the chlorination process is not enough to bring them within the allowed standards

18 Recommendations The drinking water quality should not be considered as an isolated parameter of water supply, but as an important element that affect directly the health of the people. Because the water supply organs are responsible for the quality and safety of drinking water, there is a need to combine good operation techniques and preventive measures supported by continuous monitoring and control of the quality. A special attention should be made to microbiological characteristics of quality. The potential consequences linked to microbial contamination are so unpredictable that microbial control should always be of a primary importance and during it no changes or compromises should be made. The improvement of drinking water quality is closely related with its systematic monitoring. The establishment of a well-planned survey system in time and space will positively affect the safety of drinking water. Defense measures of water sources should be made according to their type. In the case of underground water sources, protection around them should be enforced, not allowing human activities within a certain radius. For surface waters, the selection of treatment processes should be oriented towards a greater water quality and safety. The sanitary inspection organs should expand and intensify their controls in the entire supply network. This will prevent future contaminations and diseases. During disinfections compromises should not be made in attempt to control disinfection by- products. Lowering the level of chlorine in the network is not commendable for the moment as the network is in a poor technical situation, but its level should be kept constant and within allowed values. Measures should be made to improve the disinfection process and in particular for the level of chlorine in the network. The fluctuations of chlorine level from very high to very low values can bring negative impacts on health. The promotion of automatic chlorinating systems should be promoted to replace manual chlorination.

19 MERCI! THANK YOU! HVALA!


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