Spatial Analysis of Groundwater Quality Indices across Yenagoa Communities in Bayelsa State, Southern Nigeria

Water Quality Index (WQI) and Geographical Information Systems (GIS) was successfully integrated to assess and present the groundwater quality status of communities of Yenagoa in a map form. Physico-chemical analysis was carried out on fifty (50) representative groundwater samples from shallow boreholes across communities in the area. Result obtained was used to compute the WQI of samples and classify them into groups of excellent (24%), good (18%), poor (52 %) and unsuitable (6%). Results from classification and borehole location information was then manipulated using GIS software to generate a WQI map for the area that can be interpreted by all and sundry. The presented map showed communities in the North-Eastern parts of Yenagoa comprising Nedogo-Agbia, Akemfa and Yenegwe and some random areas comprising Ogu, Akempai, Azikoro and Swali have poor groundwater. South-Western parts of the city the showed good water, this was observed in Ayama-Ijaw, Obololi, Ikibiri and Ikudu communities. Central communities of Bomodi, Tombia and Akaibiri had good groundwater. Ekeki, Famgbe, Yenaka and Kpansia showed excellent groundwater quality, while some communities in Eastern and North-Eastern Yenagoa had very poor groundwater which is unsuitable for consumption as seen in Edepie, Agudama and Igbogene. Appropriate treatment measures are strongly recommended for places on the WQI map of Yenagoa showing poor and unsuitable groundwater quality to forestall health challenges that may be associated with using such water directly.