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Geographic Area 

The report covers Porirua City, located within the Wellington Region of New Zealand, focusing on the rural–urban interface zones. 

Summary of the Report 

This report, prepared by Forme Consulting Group Ltd for the Wellington Regional Council, assesses wildfire hazard in Porirua City. It is part of a broader initiative to develop a regional strategy for managing wildfire risk. The study focuses on the rural–urban interface, where vegetation and human activity intersect, increasing the potential for fire hazards. 
 
The hazard assessment model used in the report includes four key elements: vegetation type, curing and weather (including aspect and rainfall), slope, and proximity to people. Each factor is scored and combined to produce a wildfire hazard rating. Areas with breaks in vegetation, such as roads or lawns, are considered to have lower risk due to defensible space. 
 
High hazard areas identified in Porirua City include scrub pockets in Cambourne, Paremata, and Whitby; the northern and southern fringes of Porirua East; scrub at Onepoto; scrub between Whitby and Waitangirua; and the coastal slope at Pukerua Bay. Gorse north of Plimmerton is also high risk, though few buildings are exposed. 
 
The report recommends targeted hazard reduction strategies. For existing buildings, it suggests increasing defensible space through lawns, paths, and firebreaks, replacing flammable vegetation, and using structures to deflect heat. For new buildings, it advises aligning design, siting, and materials with the hazard level and ensuring adequate setbacks and vegetation management. 
 
Vegetation management is emphasized as a key strategy. Succession to less flammable native species is encouraged, and mechanical methods like mowing and grazing are preferred over burning, which can increase gorse growth. Building measures include using non-flammable materials, avoiding stilts on slopes, and removing combustible debris near structures. 
 
The report includes hazard maps and GIS data showing vegetation, rainfall, slope, aspect, and human activity overlays. These tools support further analysis and planning. Overall, the report provides practical guidance for reducing wildfire risk in Porirua City through informed land use and building practices.