Optimization and planning of water resource management in the Mé watershed using the WEAP Model for Abidjan’s drinking water supply

Abstract

The availability of water resources is a key factor in the socioeconomic development of southeastern Côte d’Ivoire. The WEAP (Water Evaluation and Planning System) model was used to assess current and future water demand in the Mé watershed, in the context of its use to supply drinking water to the city of Abidjan by 2060. The analysis incorporates several key factors, including water resource availability, climate change, population growth, and deforestation, which are considered major variables influencing the balance between demand and the capacity to meet it. To this end, three scenarios were developed and evaluated: the baseline scenario (SR), the climate change and reforestation scenario (SCCR), and the scenario reflecting the combined effects of climate change, population growth, and deforestation (SCCCDD). The results highlight a continuous increase in water demand across the four municipalities supplied by the Mé watershed, underscoring the eventual need to rely on alternative sources of drinking water to address future shortfalls. However, the simulation results indicate that, despite the various pressure factors taken into account, water demand remains generally met in the four municipalities throughout the study period under the “SCCR” scenario. This demand is fully met before 2040 the year in which a 1 Mm³ deficit appears in the “SCCCDD” scenario and before 2060 in the “SR” scenario, where the deficit would reach 6.15 Mm³.

Keywords: Abidjan water supply, Mé River basin, prospective scenarios, water demand, water resources management, WEAP model.