Low Impact Urban Design and Development: Catchment-based structure planning to optimise ecological outcomes

Abstract

Where receiving-water health is the driver for a change from conventional urbanisation, the logical design and management framework is the catchment (river-basin). New Zealand examples of catchment-based structure planning use a common approach that meets the objectives of the practice of Low Impact Urban Design and Development (LIUDD) One key ingredient is the clustering of buildings in catchment ‘middle lands’ removed from environmentally sensitive areas such as erosion-prone escarpments, ridges, riparian corridors and wetlands. This facilitates additional open space creation enabling ecosystem protection or restoration, the optimisation of landscape qualities and recreational opportunities. Using New Zealand case studies of Long Bay (North Shore), Flat Bush (Manukau) and Mapara Valley (Taupo) this paper reports on progressive learning across municipalities, developers and communities that have used the LIUDD approach. It demonstrates progress towards merging Integrated Catchment Management (ICM) planning with structure planning while considering ecosystem processes and receiving water objectives. Successful implementation was enhanced by the presence of champions providing leadership, and the allowance of time for institutional change and community buy-in to the process.