Groundwater Quality of Iyana-Ipaja Metropolis in Alimosho Local Government Area of Lagos State, Nigeria

Abstract

Groundwater is a source of domestic water supply in Iyana-Ipaja metropolis. The area under investigation is a hub for iron dealers and has very poor  drainage and sewage disposal systems. This study is aimed at assessing the quality of groundwater in Iyana-ipaja to ascertain the level of pollution and its suitability for domestic use. Six (6) groundwater samples comprising of three wells and three boreholes were taken, labelled MAM-W, OSTBH, OGS-W,  LAS-W, JES-BH and JAS-BH and analyzed for Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), Total dissolved solids (TDS), pH, Taste,  Alkalinity, Hardness and heavy metal contents. All samples were collected in dry season period of year 2018 and analyzed in triplicates according to  APHA-AWWA-WEF standard procedures and heavy metals using UNICAM-939 AAS after sample digestion. It was observed that MAM-W and OGS-W had  higher COD levels (150 ± 2.692 mg/L; 88.47 ± 0.659 mg/L) than the other groundwater samples while LAS-W and MAM-W had higher TDS mean values of  587 ± 6.318 mg/L and 532 ± 6.191 mg/L respectively. LAS-W also recorded highest BOD value of 5.66 ± 0.231 mg/L. MAM-W and OGS-W recorded higher  Fe levels (0.76 ± 0.05 mg/L, 0.54 ± 0.07 mg/L) which is an indication of possible seepage and leaching of iron from corroded iron rods sold in the area over  a long time, thus imparting a slight metallic taste to the water sources.