GROUNDWATER QUALITY MODELING FOR SUITABILITY FOR IRRIGATION PURPOSES IN OIL PRODUCING AREAS OF KHANA AND GOKANA LOCAL GOVERNMENT AREAS OF RIVERS STATE, NIGERIA

Abstract

This study is aimed at modeling groundwater quality for irrigation purposes in oil producing areas of Khana and Gokana Local Government areas of Rivers State, Nigeria. A random sampling approach was adopted in groundwater sampling in Khana and Gokana local government areas of Rivers State. Groundwater samples were collected from a total of twenty-two (22) boreholes in the area. Ten (10) residential boreholes were sampled in Khana while 12 boreholes were sampled in Gokana local government area. Various indices were used to determine the quality of groundwater for irrigation in the study area such as Electrical Conductivity (EC), Sodium Adsorption Ratio (SAR), Permeability Index (PI), Percent Sodium (%Na), Magnesium Adsorption Ratio (MAR), Kelly’s Ratio (KR) and Potential Soil Salinity (PS). In Khana area, all the water samples have PI values which render the groundwater unsuitable for irrigational purposes. Meanwhile, in Gokana, the groundwater samples show good to excellent quality for irrigation purposes. A high permeability index enhances crops yield, because the soils becomes more aerated and allows flow to occur easily, carrying plant nutrients from one part of the soil to the other. All groundwater samples in the area plotted in the C1-S1 (low sodium hazard and low salinity), C2-S1 (low sodium hazard and moderate salinity) and C3-S1 (low sodium hazard and high salinity) category which represents low sodium hazard and low salinity hazards and are therefore suitable for irrigation.

Keywords

• modeling
• irrigation
• groundwater
• borehole
• soil productivity
• oil producing areas.