Water productivity and food security in Sub-Saharan Africa: a productivity pathway

Achieving food security in Sub-Saharan Africa requires efficient resource management within agribusiness systems. This Study analysis the economic role of water productivity (WP) in linking agricultural production to food security. Using panel data from 45 countries (2004–2024), this research assesses how water productivity mediates this relationship, moderated by land availability and agricultural economic development. This evidence is crucial for designing cost-effective agricultural and water policies. The analysis reveals that a 1% increase in water productivity is associated with 0.791% higher food security, with this effect being significantly stronger in low-income countries and regions with greater agricultural land availability. However, the interaction between agricultural GDP (AgriGDP) share and WP is positive (β=0.878, p<0.1), indicating that the association between WP and food security strengthens as the agricultural sector contributes more to the economy. Heterogeneity analysis confirms WP is most effective in low-income countries. Results suggest SSA's positive WP effects reflect its irrigation expansion phase, where basic water control investments generate large gains without the rebound effects documented in more developed basins. Findings attest that WP shows a significant direct (β=0.084) and indirect (β=0.028) association with food security. These pathways are amplified by agricultural land (β=0.127) and strengthened by a higher AgriGDP share interaction. Economic policies must integrate targeted water management with land tenure reforms and financial incentives, while also establishing caps on water extractions and basin-scale water accounting to prevent future rebound effects. These integrated strategies are essential for strengthening the agribusiness, improving rural incomes, and achieving sustainable development in the region.