Application of the watershed sustainability index to drainage basins in Akwa Ibom, South-South Nigeria
Abstract
Watershed Sustainability Index is an indicator which assesses the sustainability in the basin. It contains many components as the parameter and, sub-indicators. These components represent the influence on the sustainable development of the river basin. Water Sustainability Index (WSI) of the senatorial districts of Akwa Ibom State with three randomly selected communities within each senatorial district, were investigated. Watershed population was estimated from data obtained from the National Population Commission (NPC). Average WSI for Uyo senatorial district watershed reveals that the final averages are 0.63, 0.57 and 0.57 for Obio Offot, Nung Udoe and Ifiayong. The overall WSI score was 0.59 denoting an average sustainability. For Ikot Ekpene senatorial district watershed, it was observed that the final averages are 0.58, 0.55 and 0.55 for Ikot Ubo, Ikot Osurua and Ikot Etefia, it has an overall WSI score of 0.56 representing an average sustainability. For Eket senatorial district, it was revealed that the final averages are 0.59, 0.59 and 0.57 for Ikot Ibiok and Idua Eket and Esit Udua, it has an overall WSI score of 0.58 denoting an average sustainability. The study revealed that the most critical indicators was related to the hydrological component, namely: The State sub-indicator, which is associated with low water availability per capita; the Response Sub-indicator which is related to high loss rates in the district; and the water quality-Response sub-indicator, which is accentuated by the lack of sewage collection and treatment in the herein studied watersheds. The study infers that the watersheds require priority attention in the hydrological dimension, especially as it concerns sewage collection and treatment, as well as to water supply. And it would be important to note that the resolution of these two critical points may, in turn, solve other issues associated with the population’s health as well as the improvement of the quality of life in the watersheds.
