Abstract
Kazakhstan faces growing water security challenges driven by climate variability, demographic pressures, and legacy infrastructure. This study applies the System of Environmental Economic Accounting – Ecosystem Accounting (SEEA-EA) framework to the Astana Reservoir, the primary water source for the capital city, to integrate ecosystem services into water planning. Using spatial analysis, hydrological monitoring, and valuation techniques, we quantified four key services—water supply, purification, erosion control, and recreation—and assessed their economic value through market pricing, avoided cost, and travel-cost methods. Results indicate annual ecosystem service values of USD 59.7–80.9 million, dominated by purification and water supply functions. Despite these contributions, declining storage capacity, sedimentation, and water quality trends threaten long-term sustainability. Stakeholder interviews indicate strong support for embedding ecosystem service valuation in policy to enhance transparency and resilience. The findings demonstrate SEEA-EA’s potential to inform evidence-based water governance in Kazakhstan and similar contexts.