ASSESSMENT OF GROUNDWATER QUALITY USING WATER QUALITY INDEX (WQI) METHOD IN SOUTHERN IJAW LOCAL GOVERNMENT AREA OF BAYELSA STATE, NIGERIA

This study aims at using Water Quality Index (WQI) method for groundwater assessment in some communities in Southern Ijaw Local Government Area of Bayelsa State, Nigeria. A total of fifteen (15) communities within the LGA were selected and groundwater from hand-dug well (HDW-15 samples) and borehole (BH-15 samples) was sourced during the wet season (July) and dry season (March). The analyses for water quality index was carried out through laboratory APHA standard. The weighted arithmetic water quality method was applied to assess water suitability for drinking purposes. The Quality Index indicated that HDW (67%-good and 33%-poor) and BH (87%-excellent, 13%-very poor) quality during the wet season and HDW (80%- good to excellent, 20%-poor) and BH (100%- good to excellent) during dry season. Spatial variation of water quality index maps for HDW show most deteriorated groundwater quality is centered within hand dug well towards the western part of the area during both wet and dry seasons respectively. Continuous monitoring of the water quality, improvement of environmental quality and sanitation practices is advocated and advised.