Bacterial Examination of Wells of the Maâmora Tablecloth: A community based survey in Kenitra, Morocco
Abstract
Pollution of water resources is a global problem. Unfortunately, groundwater is more sensitive to contamination by industrial waste, agriculture, household waste and wastewater that lead to physicochemical (pesticides, heavy metals, nitrates) and biological (viruses, bacteria, parasites) pollution. Bacterial contaminations of water are responsible for the emergence of many serious epidemic diseases (Cholera, Typhoid, Tuberculosis etc). The purpose of this study is to find out the impact of farms intensification and untreated sewage discharges on the microbiological quality of Maâmora water wells. Initially, bacteriological analysis done to identify not only pathogenic faecal germs but also indicator germs which have the same origin and which indicate that the water has been in contact with feces. In a second step, these identified germs were counted. Germs included in this study were Escherichia coli and Streptococci. Analysis were done about total & faecal coliforms and faecal Streptococci from the raw water of 16 boreholes on the Maamora aquifer, Kenitra. Microbiological analysis of the waters of these studied boreholes were compared with WHO standards of potability i.e. Zero bacteria/100mL for Faecal Coliforms, Total Coliforms and Faecal Streptococci. This study reveal that there was more (33% to 42%) contamination in studied wells with total germs who attained 1 to 13 bacteria/1mL. These results calls for an improvement of the control water quality of the Maâmora and develop vigilance tools for decision-makers to managers.
Keywords
Download Options
Introduction
Many microorganisms, viruses, bacteria and protozoa, even fungi and algae are present in the water. 1 The anaerobic conditions generally encountered in groundwater. Bacteria, viruses, and other pathogens found in groundwater come from septic tanks, landfills, sewage spreaders, livestock, fermented materials, cemeteries, and surface water discharges. 2-4 These pollutions can also be due to leaks of pipes and sewers or the infiltration of surface waters.
The great majority of these harmful microorganisms, likely to generate formidable human infections. Drinking water must not contain pathogens, which could lead to biological contamination and cause an epidemic. 5-6 For this purpose, the National Office for Drinking Water (ONEP) and the Autonomous Board of Water and Electricity distribution (RAK) are responsible for the control of the bacteriological quality of water & intended for the production of drinking water for human consumption. 7
The microbiological monitoring of drinking water concerns the following parameters: thermo-tolerant coliforms (Escherichia coli, Enterobacter cloacae, Salmonella, Yersinia enterocolitica etc), faecal streptococci (Streptococcus bovis, S. equinus, S. gallolyticus, S. alactolyticus and Enterococcus faecalis, E. faecium) and aerobic bacteria revivable at 22 °C and at 37 °C. 8-9 .
Conclusion
According to the WHO and others authors, about 30000 people a day, about 10 million a year, die because of inadequate or poor water supply and deplorable hygiene conditions. 16-19 A bacteriological examination can only be validly interpreted if it is carried out on a sample taken correctly, in a vial present during the sampling. The sample should be stored in a cooler from 0 °C to 4 °C. The analysis must be carried out as soon as possible after sampling within a period not exceeding 24 hours, otherwise the sample must be fixed at the time of sampling by adding exactly 2 ml of a mercuric solution (HgCl2) at 20g / L one litter of sample. TC and FC, FS are counted using the filter membrane method. The result of the bacteriological analyzes reveals the contamination of the raw water resulting from the Drilling carried out by the RAK by two types of bacteria: Total sprouts at 37 °C and Total germs at 22 °C. While the results found in treated water showed a complete abatement of the bacterial population at the level of ONEP boreholes. The present study revealed a high risk of contamination of unprotected wells up to 67%, contamination of water from open wells in contact with wind and other bacterial sources. There is an urgent need to ensure good closure and well sealing of wells to prevent the release of waste or the fall of animals or contamination by raw sewage from septic tanks. The present study should be supplemented by the search for other pathogenic bacteria20-22 such as Staphylococci, Salmonellae, Vibrio and Chlostridium.