Monitoring Water Quality of Birim River in Ghana Using Geographic Information System and Remote Sensing

The impact of Artisanal and Small-Scale Mining (ASM) on surface water quality is a growing concern in Ghana. Issues of water scarcity, shortages and closure of treatment plants is on the increase in the Atewa Enclave mainly due to the antagonizing effect of ASM Land Use (LU) on the Birim River. Due to the changing rate of water quality, ground-based surveys are unlikely to be feasible, especially for continuous monitoring. This study employed Geographic Information System (GIS) and Remote Sensing, with the aid of supervised classification and the Markov-CA, to predict and model the water quality of the Birim river for continuous monitoring and impact analysis. A combination of the in-situ water quality data together with Modified Normalized Difference Water Index (MNDWI) was used in a regression model to simulate the water quality parameters for a said year. The rate of change across all LULC classes was barely significant from 1991-2001. The MNDWI values for 2001 were very low depicting very low spectral reflectance of water. The rate of change in the ASM Land Use (LU) recorded highest peak, 520.21 Ha/yr. This shows ASM as the major driver of LULC change in the Atewa enclave with a very high impact on water quality. The linear regression model of iron showed a strong positive correlation which translated into an R-square of 0.5, a high level of significance of 0.0242 and a high correlation of 0.7345. The research explained how spectral reflectance correlates with water quality parameters a basis for