Planning for Water Sensitive Design in a Growing City

The nature and effects of stormwater runoff are integrally linked to land use and development practices. Past development has resulted in significant reduction in water quality, and health of freshwater and coastal water bodies from increased stormwater runoff and contaminants, as well as increasing flood risks. Addressing effects in existing urban areas retrospectively, if possible, is often prohibitively expensive. Water sensitive design and on-site management of stormwater quality and quantity are increasingly applied to new development to achieve improved outcomes.

Development of Auckland Council’s Proposed Auckland Unitary Plan (the Plan) provided an opportunity to extend water sensitive design approaches across the region and all stages of development to improve integrated land and water management, and sustain and enhance freshwater and coastal water environments, while also enabling significant growth provided for in the Plan.

The approach focuses on reducing the generation of stormwater runoff and contaminants, and then managing them at source, using land use controls in conjunction with discharge provisions. It also seeks to minimise adverse effects of new development and progressively reduce existing effects at the time of redevelopment. There were significant challenges associated with integrating this approach across the Plan which are explored in this paper.