Contrasting Hydropower Development Strategies in Central Asia’s Water–Energy–Food Nexus Through Spatially Explicit System Dynamics Modelling

Central Asia faces increasing pressure on transboundary water, energy and food systems, particularly in the Aral Sea Basin, where hydropower, agriculture and downstream water availability are closely linked. This study applies a spatially disaggregated Water–Energy–Food (WEF) Nexus System Dynamics Model under combined climate–socioeconomic scenarios (SSP1-2.6, SSP2-4.5 and SSP5-8.5) to assess hydropower development and policy pathways at basin and sub-basin scales in the Amu Darya and Syr Darya basins during 2015–2050. At basin scale, mean annual water supply remains stable across scenarios, at approximately 42 and 87 million hm3/year, respectively. Under national hydropower plans, installed capacity nearly doubles by 2050, reaching 10.45 and 10.65 GW, respectively. Food supply is more sensitive to climate–socioeconomic pathways than to hydropower expansion, with 2050 values ranging from 1120 to 1370 tonnes in the Syr Darya and 1405 to 1780 tonnes in the Amu Darya. Spatial simulations show that upstream-only development concentrates energy gains, whereas integrated basin-wide planning delivers more balanced WEF outcomes and the highest Aral Sea inflows, reaching 8.41 million hm3/year and 17,319 hm3/year, respectively. Persistent Amu Darya trade-offs underscore the need for transboundary coordination in reservoir operation, irrigation planning and downstream-flow safeguards. Spatial disaggregation reveals trade-offs concealed by basin-scale averages.