Island nations like Tonga rely heavily on groundwater and rainwater harvesting for their freshwater needs. Water resource management in island nations presents unique challenges due to limited freshwater sources, increasing salinity, and the impacts of climate change. Effective monitoring and management of water resources are crucial for ensuring sustainable water supply. This study aims to explore and enhance the evaluation of rainwater harvesting potential and planning in Tonga using GIS and deep learning technologies. The primary objectives are to identify suitable rainwater catchment areas, estimate the volume of harvestable rainwater, and assess the sufficiency of this water in meeting local needs. High-resolution aerial imagery and GIS tools are employed to detect and map roof surfaces and water tanks and integrate rainfall data to model potential water collection. Additionally, community water consumption patterns are analysed to compare supply with demand. Preliminary results indicate that rainwater harvesting can substantially contribute to the freshwater supply in Tonga. However, challenges such as variability in rainfall and storage capacity limitations need to be addressed. This study highlights the critical role of GIS technology in optimizing rainwater harvesting systems, providing a framework for enhancing water security in island nations. Future research should focus on long-term monitoring and the integration of rainwater harvesting with other sustainable water management practices.

This Great South and Southland District Council joint presentation showcases the development of the Southland Sea Level Rise model and the creation of the council's first publicly released Esri ArcGIS StoryMaps. The presentation demonstrates how GIS was used to engage the public and make information more accessible and interactive.

The model forecasts potential coastal flooding areas due to the combined effects of sea level rise and extreme sea levels using Ministry for the Environment set scenarios.

Identification of flooded areas was achieved by reclassifying high-resolution Digital Elevation Models derived from LiDAR. The modeling includes variations in Mean High Water Spring, Vertical Land Movement, and topography.

Results include report maps and StoryMaps of flooded coasts for climate change scenario SSP5-8.5 in the years 2090, 2130, and 2300. These are crucial for understanding the long-term impacts of sea level rise and aiding in future planning and mitigation efforts.

This project provides a foundation for other regions to model sea level rise according to Ministry for the Environment guidance. It also exemplifies how StoryMaps can be used to effectively communicate and engage local government communities with GIS information. By making complex data accessible and interactive, we can better inform and prepare New Zealand communities for the impacts of climate change.

This presentation showcases the success of geospatial innovation in delivering Impressive outcomes for Auckland Council and the Auckland community as part of their climate change adaptation plan. Utilising the Esri suite, we overcame significant challenges, including large data volumes, complex and evolving risk frameworks, a diverse audience, and COVID-19 disruptions to community engagement. This resulted in a comprehensive package that enables Auckland Council to make informed adaptation decisions for the future. Deliverables included web and in-person community facilitation materials, experience builders and dashboards for asset managers and program directors, technical maps for reporting, and a fully automated risk assessment data flow for over 70 asset types.