Abstract:
Introduction: Rapid population growth and urbanization has significantly resulted in higher demand on groundwater resources in urban and peri-urban areas. However, anthropogenic activities and poor protection of groundwater, are potential sources of contamination posing health risks. To access the faecal contamination pathway to determine the quality of groundwater, the World Health Organization (WHO) developed a sanitary risk inspection protocol to identify potential risks and hazards. The study therefore sought to assess the relationship between observed sanitary risks and water quality parameters indicating faecal contamination in urban and peri-urban groundwater sources in Greater Accra, Ghana.
Method: The study used a descriptive cross – sectional study, that was carried out in 5 selected enumerations areas (EA) in the Greater Accra Region. After selecting the households with groundwater sources, hazards (sources of contamination) were identified and water samples taken for physico-chemical and bacteriological laboratory analysis, using international standard procedures. Statistical analysis of the results was carried out using SSPS version 22.
Results: The sources of contamination identified within the periphery of the groundwater sources were bath-houses, hen coups, piggery, pit latrines, polluted swamps, refuse dumps, septic tanks and urban storm drains. Nitrate levels ranged from 0.7mg/l to 19.7mg/l with a mean of 6.4mg/l. Chloride levels ranged from 35.43mg/l to 421.15mg/l with a mean of 121.24mg/l. Nitrite levels ranged from 0.002mg/l to 4.192mg/l with a mean of 0.23mg/l. Electrical conductivity ranged from 0.56mS/cm to 7.24mS/cm with a mean of 2.29mS/cm. Total coliforms counts ranged from non-detection to a maximum of 2400cfu/100ml with a mean of 50.8cfu/100ml, Faecal coliform counts ranged from non-detection to a maximum of 450cfu/100ml with a mean of 14.69cfu/100ml and E. coli counts ranged from non-detection to a maximum of 200cfu/100ml with a mean of 10.55cfu/100ml. Multiple regression model
used showed that faecal contamination pathways such as depth of groundwater and distance of groundwater from source of contamination were additional explanatory power used to predict faecal contamination of groundwater.
Conclusion: The findings of the study showed that there was a relationship between the modified observed sanitary risks and water quality parameters indicating faecal contamination of groundwater in urban and peri-urban areas in Greater Accra Region, Ghana.
