THE WATER QUALITY OF BOREHOLES NILE RIVER WATERSHED (JIJEL, ALGERIA).

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1 Proceedings of the 3 th International Conference of Environmental Science and Technology Athens, Greece, -7 September 3 THE WATER QUALITY OF BOREHOLES NILE RIVER WATERSHED (JIJEL, ALGERIA). N. BALLI AND E. LEGHOUCHI Biotechnology- Environment and Health laboratory, department of animal and vegetal biology, BP 98, Ouled Aissa, Jijel-8 Jijel, Jijel 8, Université de Jijel; belli_nana@yahoo.fr Biotechnology- Environment and Health laboratory, department of animal and vegetal biology, BP 98, Ouled Aissa, Jijel-8 Jijel, Jijel 8, Université de Jijel; leghouchi_s@yahoo.com EXTENDED ABSTRACT This study aims to assess the chemical quality of drinking water resources in the catchment of the river Nile, characterized by a large agricultural potential, especially in the irrigated by the waters of the wadi. The intensity of farming activities deployed in this basin subject the groundwater to several opportunities for contamination. However, in the town of Jijel, the main source of satisfaction in the demand for drinking water is ground water from the `holes drilled in this basin. The electrical conductivity, ph, COD, BOD, temperature, nutrient, phosphate, dissolved oxygen content and trace metals (cadmium, lead, zinc, copper and manganese) have we premeasured to assess the potential impact of agricultural activities on the quality and suitability of water boreholes. For this purpose, chemical analysis was performed in water samples from eight wells supplying the city of Jijel in drinking water. Keywords: Chemical water quality, agricultural watershed, contamination, river Nile.. INTRODUCTION Water is an essential component for life on Earth, which Contains minerals extremely important in human nutrition (Versari et al., ). However, the dramatic increase in population resulted in an enormous consumption of the world s water reserves (Ho et al., 3). Due to their environmental persistence and biogeochemical recycling and ecological risks, heavy metals are hazardous pollutants in the drinking water. Metals enter the aquatic environment from a variety of sources. Although most metals are naturally occurring through the biogeochemical cycle (Garret., ), they may also be added to environment through anthropogenic sources, including industrial and domestic effluents, use of agricultural chemicals, urban storm, atmospheric sources and boating activities (Forstner and Witmann.,999). The supply of safe potable water has significant impact on the prevention of water transmissible diseases (Lerda et Prosperi., 996). The abundance of heavy metals, organic compounds, toxic chemicals, radionuclides, nitrites and nitrates in potable water may cause adverse effects on the human health such as cancer, and chronic illnesses (Ikem et al., ). Therefore, it is essential to constantly monitor water quality used for drinking purposes (Zhao et al., ). Jijel is located in northeast part of Algeria (See figure ), covering 398 Km, the mean annual temperature is ranging from,6 to 6, C and mean annual precipitation of 9, to89, mm (ONM., ). The area of our study is located in the coastal region of Jijel,

2 which characterized by plains and valleys located mainly in the north, along the coastal strip. Heavily populated with high agricultural potential (The total agricultural area is estimated at 99,4 ha, half of the total area of the province), they occupant 8 % of the total area of the province. The total capacity of the aquifers in this area is estimated at round 73,8 hm 3 /year. The exploitation of these sheets is done through the spring, wells and boreholes. These are located mostly in the Nile river watershed.. MATERIALS AND METHODS.. Sampling area Figure. Geographic localization of Jijel. The drinking water samples were collected from 7 different boreholes located in the Nile river watershed which extends about twenty kilometers southeast of the city of Jijel area and is occupied 68 km divided into two sub-watersheds respectively 48 km and km south. It is bordered to the west by the watershed of the river Djendjen and is one of the Wadi el-kebir in the south, the watershed is limited by the contours of the part beyond Kabylie quickly m above sea level, with the Mediterranean Sea is its natural limits (See figure) (ONM., ).The watershed is drained by the Nile river and its two tributaries, the wadis Sa'ayyoud and Bukhara. These three wadis flow from south to north.with an annual throughput of 3 million m 3 at the mouth, the Nile river is one of the most important wadis in the region of Jijel.

3 Figure.The map of the river Nile (:,). In this study, we collected samples of groundwater catchment of the Nile river to the physico-chemical analysis. These samples were collected in 7 holes numbered ( See figure 3): ON 3, ON 7, ON 34, ON 4, ON 3, ON 33 wells supplying the city of Jijel. ON: drilling supplies the city of Taher... Analysis of water Figure 3. satellite image. Samples directed to heavy metals determination were filtered through a <, 4 µm poresize membrane filters. The ph of the filtrate was set to ±, with the ultrapure HNO 3 (Merck 6%) and stored at 4 C until the analysis. The stock solutions of all reagents were prepared using ultrapure water and all standard solutions were made daily by diluting the stock solution with acid nitric (, M) (Tamasi

4 et Cini., 4). In the sense to prevent the sample contamination with metals, all the glassware and plastic containers were washed once with acid nitric (, M) and rinsed with ultrapure water. Electric conductivity (EC), temperature, ph and dissolved oxygen were measured in situ in the area sampling using multi-parameters (CONSORT C 6) and the determination of nitrites, nitrates, phosphates, chemical oxygen demand (COD) and biological oxygen demand (BOD) were performed according to standard analytic methods (Rodier., ). Atomic absorption spectrometry with flame (SHIMDZUAA 6ATOMIC) was used for the analysis of cadmium, lead, zinc, copper and manganese. 3. RESULTS AND DISCUSSION Groundwater is an important source of drinking and irrigation water in Jijel province. It is therefore imperative in this region to assess the water drilling quality. 3.. Trace metal concentrations Table shows the different concentrations of the metals analyzed. The results showed the presence of high concentrations of lead, ranged from.488 to.796 (mg L - ), cadmium, ranged from. to.644 (mg L - ) and zinc, ranged from.47to.464 (mg L - ), that far exceed the WHO required standards estimated by,;,3 and mg L - respectively (see table ). The results show that in the other part the waters of the river Nile boreholes are low concentrations of copper as well as manganese, which both show the trace concentrations. The biggest part of this harmful contamination can be attributed to the inflow of agricultural activities in the watershed of the Nil river, adding agriculture as well as others natural and anthropogenic sources which notably the mineralized of geochemical bottom, the sewages of the ancient mine of Chahna, the domestic sewages and the atmospheric deposits. Table. Heavy metal concentrations in water samples (mg L - ) (mean ±S.D., n=3). boreholes Lead Cadmium Zinc Copper Manganèse ON.3483± ± ±.99.83±.46.4±.9 ON3.368±.4.644± ± ±..344±.47 ON4.796±. 39.± ±..±.39.47±. 79 ON7.488±..479±.9.99±.9.83±.3.6±. 34 ON33.378±. 3 ON34.488±.739.9± ±3.87.6±.3.± ±.978.8±.978.4±.7.98±.9 ON3.3483±..4±..47±.3.3±.,3±,79

5 Température (C ) Table. WHO guidelines for drinking water quality (WHO, 4). 3.. Physicochemical characteristics The values of temperature in water samples (See figure 4.a) were found under the standards proposed by WHO (WHO, 4). Analogous results were obtained for the ph, EC and dissolved oxygen (See figure 4.b, 4.c and 4.d), where its values within the normal rang. Also, ammonium, phosphates, nitrites and nitrates concentrations (See figure 4.e, 4.f, 4.g and 4.h) ranged under proposed drinking water quality standards (WHO, 4). Chemical oxygen demand (COD) values observed (See figure 4.i) were in according to the proposed standards, only ON 7 is the exception and shows a relatively high amount compared to other boreholes. By eliminating this value, we can say that the pollution load is very low. In addition, the values of biological oxygen demand (See figure 4.j) in all water samples which into the rang, suggested by WHO. The boreholes waters in Nile river watershed are naturally pure and vivid and they are intended for human consumption. 3 Température Figure 4. a.

6 Oxygène dissous (mg/l) Conductivité (µs/cm) ph ph Figure 4.b. Electric Conductivity Figure 4.c ON Dissolved oxygen ON3 ON4 ON7 ON33 ON34 ON3 Figure 4.d.

7 Nitrite (mg/l) orthophosphate (mg/l) Ammonium (mg/l) Ammonium Figure 4.e Phosphate Figure 4.f Nitrite Figure 4. g.

8 DBO mg/l DCO (mg/l) Nitrate (mg/l) Nitrate Figure 4.h. 3 Chemical oxygen demand Figure 4.i Biological oxygen demand Figure 4.j. Figure 4. (a), (b), (c) and (d). water temperature, ph, EC and dissolved oxygen of boreholes Nile river watershed, (e). Ammonium concentrations of boreholes Nil river watershed, (f). Nitrites concentration of boreholes Nil river watershed, (g) nitrates concentration of boreholes Nil river watershed, (h) and (I) water COD and BOD variations of boreholes Nil river watershed. 4. CONCLUSIONS In conclusion, all the results we have obtained can signal an alarming contamination of water boreholes by lead and cadmium in particular. Following these results, we conclude, in particular for the physic-chemical quality of the water analyzed, the strong contribution from the geochemical bottoms in addition the contribution of agricultural activities in the watershed of the Nil river.

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