Gis-based Analysis of Water Quality Parameters of Groundwater with Proximity to Onsite Wastes Pits in Vom Community of Jos South, Nigeria

Water quality assessment is an important part of environmental quality management especially in groundwater resources located close to sources of contamination. This study involved the assessment of groundwater quality for hand dug wells at locations with proximity to pit latrines in Vom community, Plateau State, Nigeria and the use of GIS for data analysis. Water samples were collected from six (6) locations in a small area to assume possible interaction between the water in the sampling wells, the maximum distance between any two points being 100 m and the minimum distance being 22 m. Eleven (11) physical, bacteriological and chemical parameters were analyzed for the water samples. The results were compared with World Health Organization and Nigerian Standard for Drinking Water Quality standards. The chemical parameters in the samples tested met the WHO and NSDWQ limits with the exception of pH which was slightly acidic for four samples. The results also showed that E. coli was found in all the samples tested. This may be attributed to the proximity of the wells to pit latrines. The results obtained from laboratory analyses were inputted into a GIS database in ILWIS 3.8 where the variation maps were developed and also classified maps for each of the parameters based on whether they meet WHO standards or not. The classified maps were all overlaid in GIS to develop the groundwater quality information map where any point highlighted gives information on the parameters for that point. This makes the retrieval of water quality parameters easy and also the comparison of the parameters with respect to location. Treatment of the groundwater with chemicals like soda ash and chlorine are recommended before consumption. It is generally recommended that wells should not be located in close proximity to onsite underground wastes disposal pits. Government should provide sufficient potable water for the Vom Community.