Seasonal quality of water sources indicated by Escherichia coli: a case of Elobied, North Kordofan state, Sudan

Abstract

Sudan is rich of water resources; however, the seasonal quality of water sources is largely unknown particularly in North Kordofan region. This study was designed to test the seasonal (winter, summer and autumn) quality of water sources in El Obied, North Kordofan State, Sudan. A number of 261 water samples (87 samples per season) were collected from Hafirs (excavated either by hand or machine and used for storage of surface water), Gerab (big water containers made from plastic and used to store water at homes), hand pumps, distribution network, households’ containers and elevated water tanks in 2014/2015. Membrane filtration technique was used to investigate water samples. Escherichia coli or E. coli count was performed according to WHO and Sudanese Standards and Measurement Operation. The results illustrated that all samples collected showed positive results of E. coli which indicate poor water quality in the region. Proportion of contamination was highest in Hafirs, Gerabs and household containers across seasons. Hafirs samples were 100% contaminated across seasons. In autumn, Gerab and household containers samples showed 60% and 58% contaminated samples. In the summer season, the results showed 54% of Gerab, and 50% of the households’ containers were contaminated. In winter season, prevalence of E. coli revealed that 67% of households’ containers and 58% of Gerabs samples were contaminated. Greater contamination (60%) of the water sources was indicated in autumn followed by (55%) in winter and (51%) in summer season. Results showed significant contamination of water sources across seasons. Results indicated that elevated water tanks and hand pumps (groundwater sources) were safe compared with surface water source. The study recommended regular test to water sources across seasons to protect human and animal life.