Navigating Urban Hydrology: A Comprehensive Exploration of Impervious Area Reduction Techniques in New Zealand's Residential Landscapes

Purpose: Impervious surfaces have emerged as a critical indicator for assessing the impacts of urbanization on water resources, with recent flood events in New Zealand (NZ) highlighting their significance in urban water management. While traditional stormwater control measures rely on total impervious area calculations, this study examines the effectiveness of impervious area reduction techniques in residential areas across NZ, with particular attention to implementation challenges and policy frameworks.

Design/methodology/approach: The research conducts through semi-structured interviews with 18 experts, including government officials, consultants and developers. This qualitative approach allows for an in-depth exploration of various perspectives on urban water management strategies and their effectiveness.

Findings: The study reveals several key findings: (1) current strategies exhibit varying effectiveness depending on scale, with catchment-level solutions being more successful than site-specific interventions, (2) significant challenges to implementation exist, such as resource constraints, limited monitoring capabilities and coordination issues among stakeholders and (3) there is a need for stronger national-level guidance and better integration in regulatory frameworks between district and regional plans.

Originality/value: This research contributes to the existing knowledge on urban flood resilience by identifying promising opportunities for improvement in urban water management practices in New Zealand. It emphasizes the importance of enhanced public education, innovative technical solutions and market-based incentives as practical recommendations for policymakers and practitioners.