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Purpose of the Report: 

To assess current and future flood exposure across the Wellington Region to inform planning and risk management decisions. 

Geographic Area Covered: 

The report covers the Greater Wellington Region, including its cities, towns, and rural districts. 

Summary of the Report: 

The Wellington Region Flood Exposure Assessment, prepared by Tonkin & Taylor Ltd for the Greater Wellington Regional Council, provides a comprehensive analysis of flood risks across the region. The report highlights that approximately 31% of the region's population and buildings are currently exposed to flooding during a 1% Annual Exceedance Probability (AEP) event. This exposure is expected to increase significantly by 2110 due to climate change and urban development, with up to 230,000 people potentially affected. The assessment evaluates the vulnerability of critical infrastructure including emergency services, utilities, and transportation networks. Lower Hutt City is identified as the most exposed area, with substantial impacts on residential and commercial buildings, as well as infrastructure. The report also examines the effectiveness of existing flood protection measures such as stopbanks and identifies areas where these defenses may be insufficient. Future urban growth areas and renewal zones are assessed for flood risk, emphasizing the need for careful planning to avoid exacerbating exposure. The report concludes with a discussion of environmental, social, economic, and legislative challenges and opportunities in flood risk management. It advocates for nature-based solutions, integrated planning, and increased community engagement to enhance resilience. The findings aim to support informed decision-making and strategic planning to mitigate flood impacts across the Wellington Region.