Assessing the potential of a surface water body for multiple uses. Case study: the Anambra River Basin, south-eastern Nigeria

Abstract

Anthropogenic activities causing deterioration in water quality and a decrease in meeting the ecosystem service potentials of surface water are considered one of the major basic environmental challenges. Water samples were collected from three sampling stations (Ogurugu, Otuocha, and Otu- Nsugbe) in the Anambra River Basin and analyzed following standard protocols and procedures for nine months. The cosystem services potentials of the Anambra River Basin were evaluated using physico-chemical parameters and some indices: Comprehensive pollution index (CPI), nutrient pollution index (NPI), salinity potential, and soluble sodium percentage (SSP). All the water quality parameters were within the standard level for drinking water, aquaculture practice, recreation (swimming/bathing) and agricultural purposes, with the exception of pH and phosphate, whereas dissolved oxygen met aquaculture criteria only in station II. Comprehensive pollution index (0.150 – 0.449), nutrient pollution index (0.07 – 0.46), and soluble sodium percentage (6.0% -26.92%) were within the category of non-polluted or excellent to sub-clean. Potential salinity (39.39 - 97.19) was high, indicating water from the Anambra River Basin contained crystallized solutes. Conclusion: the Anambra River Basin is not at risk of eutrophication but may not support irrigation program due to the high potential salinity. However, the river needs to be monitored, and anthropogenic activities need to be regulated.