APPLICATION OF WATER QUALITY INDEX (WQI) FOR THE ASSESSMENT OF NATURAL SOURCES OF WATER IN RURAL AREAS OF LAKE ALEG IN MAURITANIA

In Aleg, Mauritania, especially in the rural areas where there is no supply of treated water for drinking and other domestic uses, natural surface water is the only source. The objective was to assess the water quality of natural sources of water in the rural areas of the BRAKNA region (in the south-west of the country) using a water quality index (WQI) for different seasons. A total of 40 samples, that is, 20 in winter and 20 in summer were collected from different sources for physicochemical analysis, and a WQI was calculated. Twenty-seven parameters were evaluated (Rrgaonkar and V. Deshpande et al. 2007). Follow-up and physicochemical analyzes made it possible to determine the WQI index. The results obtained show that raw water from Lake Aleg is classified in the category "Unsuitable" (undesirable). The overall quality of the waters is strongly influenced by the alternation of seasons of the year. Correlation analysis showed a perfect correlation between WQI and water turbidity (r = 0.999). This made it possible to specify the turbidity as a factor of deterioration in the quality of the lake waterThe water quality of the natural sources indicated that the water is poor-quality and not totally safe for human consumption, and that it needs treatment before consumption.