This Python-based geospatial project analyzes the intersection of public bus transport access and flood exposure in the Waikato region of New Zealand. It aims to identify communities, especially vulnerable populations like Māori, who face limited access to public transport and higher flood risks due to climate change.
To combine flood modelling with public bus accessibility mapping and identify meshblocks (smallest statistical areas in NZ) that are underserved and/or at risk of flooding. The goal is to support transport equity and climate-resilient planning in alignment with Waikato Regional Council objectives.
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Data Sources:
- Digital Elevation Model (DEM), river & coastline layers (LINZ)
- Official flood zones (Waikato Open Data)
- 2025 population meshblocks by ethnicity (Stats NZ)
- Bus stop locations (Waikato Regional Council)
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Flood Modelling:
- Cost-distance from rivers based on 8m DEM (5m and 10m simulated flood heights)
- Flow accumulation to model low-lying pooling zones
- Combined with official flood zones and clipped to Waikato region
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Transport Accessibility:
- Buffers of 300m, 500m, 800m created around bus stops
- Meshblocks intersected with buffer zones
- Spatial join used to classify each meshblock into:
- Serviced & Flooded
- Serviced & Not Flooded
- Not Serviced & Flooded
- Not Serviced & Not Flooded
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Overlay Analysis:
- Population exposure calculated using proportional overlay
- Māori and general population statistics assessed separately
- Expanding bus stop buffer from 300m to 800m improved service access by ~20%.
- Māori exposure in flooded, serviced areas tripled when flood height increased from 5m to 10m.
- Many areas with high flood risk lack adequate transport coverage.