GEO–SPATIAL ANALYSIS OF GROUNDWATER QUALITY FROM EKOSODIN COMMUNITY USING INVERSE DISTANCE WEIGHTING.

ABSTRACT
Groundwater is a reliable source of fresh water for domestic and agricultural water users. The observation of groundwater quality elements is essential for understanding the classification and distribution of drinking water. The aim of this study is to conduct a Geospatial Analysis of Groundwater quality around Ekosodin Community using the Inverse Distance Weighting method to investigate the physico-chemical and microbiological characteristics of groundwater quality around the study area.
In the study, the Water Quality Index of groundwater was determined for the samples collected from boreholes located within the Ekosodin Community, Benin City, Edo state. The groundwater quality parameters such as pH, TDS, calcium, chlorides, nitrates, iron, sulfates, manganese, sodium, magnesium, potassium, turbidity, and phosphate were analyzed for water samples collected from 10 randomly chosen boreholes in order to determine the WQI. Interpolation approach, Inverse Distance Weighting (IDW) was adopted in the GIS environment to quantify the spatial variability of groundwater quality over the entire geographical area. The groundwater quality maps were generated using the best fit models.
The WQI computations show that 90% of the boreholes are in excellent conditions while a minimal 10% had bad groundwater quality, making the overall deductions of the water quality of the study area to be good. The WQI maps, also shows the distribution of the various groundwater quality parameters of the geographical area. The results obtained in this study and the spatial database established in GIS will be helpful for monitoring and managing ground water pollution in the study area.