Groundwater Quality Assessment in Parts of Igwuruta and Environs, Port Harcourt, Nigeria

The study is based on the water quality assessment of groundwater in selected points in Omunwei community, Igurita, Rivers State Nigeria. Accordingly, 8 water samples were collected from Borehole Wells (N1-BH, S1-BH, K-BH, AG-BH, IG1-BH, IG2-BH, OM1-BH, OM2-BH) and analysed following standard geochemical procedures. Aquachem software was used to evaluate the hydrogeochemical facies while the concentrations were plotted using simple bar charts. Result of physico-chemical analysis show that the major cations include calcium, magnesium, sodium and potassium. The calcium content ranged from 1.40 to 5.96 mg/l with an average of 2.48±0.53mg/l. Magnesium ion (mg2+) concentration has average of 0.68±0.20 mg/l. Similarly the sodium and potassium content on the other hand ranged from 7.72 to 21.56mg/l and 0.08 to 1.45 mg/l with averages of 16.28±2.15 and 0.68±0.20mg/l respectively. For the anions, chloride was the dominant anion in the water samples and ranged from 6.00 to 22.00 mg/l with a mean value of 13.13±1.65mg/l. Sulphate concentration in all the groundwater samples ranged from 0.48 to 2.48 mg/l with an average of 1.06±0.31mg/l. These values are below the WHO [2001] limit. From the Piper Trilinear diagram as all the samples plotted within Sodium and Potassium Type and Chloride Type in the Cation Trilinear plot. On the anion trilinear plot, they indicate a Chloride facies. The Duorv plot for the studied samples indicates that the samples are dominant in the Na+K and Cl- zone. The pH part of the plot reveals that groundwater in study area is acidic. The average ionic composition analysis by stiff diagram signifies dominance of Na+ K and Cl- over the other ions in the order (Na+K) (Cl-) > (Ca2+)(HCO3+CO3) > (Mg2+)(SO4).. Judging from the results, majority of the Stiff plots have similar shapes which means that they are from the same source. Schoeller diagram was also used to present average chemical composition of the water samples. The relative tendency of ions in mg/l shows Na++K+> Cl-> Ca2+> SO4> Mg> HCO3+CO3. One basic measure of water quality is the total dissolved solids (TDS) value indicated a fresh water. The pollution Index (PI) value of 4.00 shows that the surface water bodies in the area is fit for domestic use as most parameters do not exceeded maximum permissible level set by the World Health Organization (2001) standard. The result of the study shows a mean concentration of the heavy metals as follows: lead (0.00), Zinc (0.37±0112) and iron (0.75±0.198). These values are within the permissible standard for drinking water. However, there is need for periodic groundwater monitoring to ascertain the pollution status of the groundwater system in and around the study area for its protection and sustainable development.