The Effect of Policy and Procedures on Tree-lined Streets: Increasing Urban Canopy in Sydney’s Western Parkland City

Abstract

Local residential streets that can support the growth of significant shade trees are critical for mitigating urban heat - an increasing public health risk in Western Sydney; and for increasing total urban canopy. In the state of New South Wales, regional and district plans for the rapidly developing suburbs of Western Sydney include a planning priority to increase urban canopy. However, planning controls that encourage increased density, combined with development models that continue to favour single-family, detached dwellings, result in decreased lot sizes with insufficient space to support canopy trees around homes or in the streetscape. Using a qualitative methodology, the research undertook a comparative analysis of local residential streets in two areas of the Camden Local Government Area in the metropolitan region of Western Sydney - one that was developed in the mid-1990s and the other constructed within the past three years. The investigation sought to reveal the spatial factors that contribute to the realisation of tree-lined streets. A tree-focussed reading of the urban planning and development controls, codes, guidelines and specifications that specifically apply to local streets was carried out to assess how these documents impact on the implementation of tree-lined streets. Council officers involved in the planning, design, certification and maintenance of streets were first interviewed individually and later participated together in a focus group discussion. Findings indicate that although there is political will to implement tree-lined local streets, codes and specifications for other infrastructure impact on the space available for trees. The research concludes that unless trees are accepted as a critical component of the streetscape, urban canopy will not increase and the potential for street trees to mitigate urban heat will not be realised. The discussion suggests actions for policy and for codes and practices that impact on trees. If implemented these actions would result in more tree-lined streets in Western Sydney. The actions could also be replicated in other jurisdictions.