Study of seasonal variation and index based assessment of water quality and pollution in semi-arid region of morocco

Water resources quality assessment a basic requirement for ensuring its sustainability. Groundwater resources being restricted under the earth crust are at high risk of being polluted as compared to rivers which flow continuously. This study evaluated groundwater quality in Mohammedia prefecture, Morocco in terms of physicochemical parameters and seasonal variation. The physicochemical parameters analysed were Temperature, pH, EC, TDS, Na+, Ca2+, K+, NH4+, NO2-, NO3-, PO43-, SO42. Seasonal variation was evaluated for winter and spring seasons. The water quality was assessed in terms of overall water and Pollution index. Cation/anion ratio to TDS revealed evaporation and rock weathering dominance. Based on Pollution index, water quality of 88% samples was in excellent to good category in winter season. The pollution index during winter season was <1 for all sample locations. In Spring PI was >1 only at Location P1 which was attributed to NO2-. In Spring season 78% water samples were in Good to excellent category. The decrease in concentration during spring season was attributed to lack of soil-water interaction with reduced infiltration rate. The increase in concentration of parameters was attributed to anthropogenic activities. Further studies are needed to establish relationship between infiltration rate and pollutants concentration with respect to precipitation during monsoon season. Even though water quality in majority areas was fit for consumption and domestic use still further analysis should be carried out in terms of heavy metals and other emerging pollutants.