Geosocial map as a strategic tool in local water management: the case of the Bang Rakam Subdistrict Administrative Organization, Thailand

Introduction Participatory mapping can make local environmental knowledge visible, but how that knowledge informs routine decisions in resource-constrained local governments remains poorly understood. This study examines whether a collaboratively developed geosocial map can move beyond generating participatory knowledge to support water-management planning and institutional coordination in the Bang Rakam Subdistrict Administrative Organization (SAO), Thailand. Methods A 12-month participatory action research study conducted in 2025 involved 63 core participants from policy, research, technical, civic, and economic sectors. Data were collected through participant observation, policy deliberations, two stakeholder forums, three mapping workshops, joint field inspections, GPS-based mapping, and administrative records. Thematic analysis, supported by spatial evidence, examined how collaboratively produced knowledge informed administrative practices and institutional responses. Results The collaborative process identified 17 recurring flood-risk sites and six main canals, creating a shared spatial framework that linked community experiences with technical and administrative knowledge. Residents' observations helped define locally relevant flood-warning levels, while geosocial information supported drainage and water-supply planning, complaint resolution, and coordination across agencies. The findings show how participatory spatial knowledge gained practical value through field verification, collective interpretation, and integration into administrative processes. Differences in the handling of flood-related and wastewater concerns also highlighted the institutional conditions that shape how locally generated evidence is used. Discussion The research demonstrates the potential of geosocial mapping to function as a boundary object, connecting diverse knowledge systems and facilitating collaboration across community, administrative, and technical domains. Its contribution extends beyond the production of spatial information; it also establishes institutional pathways through which local knowledge can inform public decision-making. Although sustained technical and organizational support is necessary to achieve long-term environmental outcomes, the findings suggest that geosocial mapping offers a promising means of strengthening collaborative governance and building the institutional capacity of resource-constrained local governments.