Water security and hydrosocial resilience in the Peruvian Andes: Remote sensing and cultural governance in the Razuhuillca watershed

Abstract

Droughts and water-related conflicts in the Andean mountain regions of South America have intensified in recent decades, yet limited understanding of the interaction between hydrological dynamics and culturally embedded governance systems has constrained effective water-security strategies. This study addresses this gap by integrating remote-sensing indicators (NDWI, SAVI, NBR) with ethnographic and institutional data to analyze hydrosocial resilience in the Razuhuillca watershed (Huanta Province, Peruvian Andes) between 2016 and 2025. Multitemporal Sentinel-2 analysis reveals a structural decoupling between surface moisture and vegetation vigor, characterized by increasing NDWI and declining SAVI values (r = 0.411, p < 0.001), indicating a condition of humid degradation under climatic neutrality. Cross-correlation analysis identifies a three-month lag between precipitation and vegetation response, evidencing hydrological memory and slow-release watershed dynamics. Ethnographic evidence shows that local communities interpret these changes through cosmological frameworks that conceive water and mountains as living beings endowed with memory and moral agency. Ritual offerings, rain-calling burnings, purification ceremonies, and communal patrols function as hybrid infrastructures of regulation and repair, translating ecological stress into collective action. The 2020 water-poisoning crisis, which caused widespread trout mortality and a temporary suspension of urban water supply, served as a real-world stress test of this governance system, revealing resilience as containment rather than full ecological recovery. By explicitly combining Earth observation with situated knowledge, this study demonstrates the novelty of operationalizing hydrosocial resilience through remote sensing, and contributes to Sustainable Development Goals 6 (Clean Water and Sanitation) and 13 (Climate Action) by advocating governance frameworks that integrate technical monitoring with cultural and moral dimensions in Andean and other highland watersheds.