Robert Vale

Indications from Sustainability Indicators

Sustainability Indicators are a measure to assess progress towards sustainable development, but how and why certain indicators are produced and used is often hard to understand. There is also a lack of common ground, so that different indicators cannot be directly compared. This paper explores the suitability of some existing sustainability indicators and measurement tools in this light. It suggests there is a need to develop simple local quantitative indicators in addition to the more commonly used qualitative indicators. A new method is outlined for the development of quantitative physical indicators as part of an integrated approach to a more sustainable urban environment.

Increasing uptake of low impact urban design and development: The role of sustainability assessment systems

Abstract ‘Market transformation’ of the significant urban development industry towards more sustainable practices is not moving at great pace. Design and assessment systems that may promote uptake of more sustainable urban design and development are reviewed briefly followed by a comparison between building and neighbourhood scales. For the latter there is a dearth of design and assessment tools for the residential built environment and of indicators to monitor progress towards sustainable development. Local authorities increasingly require an integrated approach to data collection and inclusion of infrastructure service providers in design, assessment and monitoring of urban development and associated environmental effects. By examining attempts to increase uptake of more sustainable residential development, the potential for tools and indicators at the neighbourhood scale to reduce environmental impact of the built environment is highlighted. It is recommended that built environment initiatives need to be combined with research into behavioural changes to achieve the desired outcome of a sustainable built environment and to increase the dialogue between communities, developers and local authorities.

Domestic energy sustainability of different urban residential patterns: a New Zealand approach

A quantitative study was undertaken to calculate the potential sustainability of five residential blocks in Auckland, New Zealand (NZ) of differing physical densities. The main study considered five attributes of sustainability: domestic energy, transportation, carbon sequestration, food, and waste. This paper presents the results and mathematical methodology developed for one key aspect, domestic energy. Using aerial photographs, Geographic Information System (GIS) and ecological footprint assessment techniques, domestic energy demand, generation and deficit were calculated. Research outcomes suggest that the classic New Zealand suburb with a density of 18 households per hectare might have the greatest potential to be more sustainable.

Typologies and Basic Descriptors of New Zealand Residential Urban Forms

This paper presents an urban taxonomy or classification system for New Zealand settlement forms across five urban scales: metropolitan/regional, sub-metropolitan/city; community/neighbourhood; local/residential block and houses/micro. It provides taxonomical descriptions and density patterns of existing and emerging New Zealand residential urban forms at neighbourhood and local levels. Considering seven case studies in the Auckland Region, this paper formulates a set of basic quantitative urban form descriptors within the urban taxonomical framework. An analysis of these descriptors indicates that dwelling and household densities and spatial distributions of built-up roof areas, vegetation, productive land, impervious pavements and pathways reflect their urban form characteristics. These varying qualities can be linked to the appraisal of environmental sustainability performances of different urban forms.

The Potential for Solar Energy Use in a New Zealand Residential Neighbourhood: A Case Study Considering the Effect on CO2 Emissions and the Possible Benefits of Changing Roof Form

Solar energy, a renewable resource, is constantly replenished by natural processes and can be used by humans more or less indefinitely. This article quantifies the potential energy from solar hot water and photovoltaics that could be generated from the roofs of the built-up areas of an existing urban neighbourhood at Glen Innes, Auckland. It examines how solar energy can contribute towards total domestic energy requirements of households for two scenarios. It also explores possibilities of enhanced potential solar contributions with changes in roof configurations. The outcomes suggest that, with minimal changes in roof configuration, the residential rooftop potential in terms of percentage contributions of total domestic energy demands (except space conditioning) could increase from 73 to 82.5 per cent for a maximum utilization scenario. For a more realistic situation, taking account of available sizes and dimensions of solar equipment the energy contribution could be enhanced from 46 to 69 per cent. Assuming a continuation of the current trends in grid-scale local generation technologies, building roofs with correct orientations to allow the collection of solar energy makes significant contributions to reducing CO2 emissions.

Metrics of Local Environmental Sustainability: A Case Study in Auckland, New Zealand

Abstract Environmental impacts, in addition to economic, social and cultural drivers, have significant implications in the evolution of more sustainable urban forms. This paper presents the results of calculating potential local environmental sustainability using ecological footprint techniques in terms of five main aspects—domestic energy; transportation; vegetation cover; food; waste—for five residential urban form case studies in Auckland, New Zealand. This quantitative study formulates a comprehensive methodology for measuring comparative sustainability performances and identifies important residential urban form descriptors. As measured in this research, low-density urban forms may have more potential to be sustainable compared with other compact urban forms which may require a change of behavioural patterns for the residents.

Utilising exotic flora in support of urban indigenous biodiversity: lessons for landscape architecture

Abstract Evidence shows that in the absence of intact natural habitats, some exotic patches of vegetation may play a compensatory role in supporting indigenous biodiversity in urban environments. This paper suggests that in urban settings where landscapes already contain non-natives, both indigenous and exotic flora may be necessary to maintain indigenous biodiversity. The research was constructed based upon a review of the current literature combined with a GIS-based spatial analysis of urban landscape patterns, using Wellington New Zealand as a case study. The research provides evidence concerning different aspects of utilising indigenous and exotic plant species to argue that a balanced proportion of indigenous to exotic plants may be advantageous in order to respond to some aspects of biodiversity loss. The results have three immediate implications for landscape architecture practices at the urban scale and reveal important issues that should be addressed by future research.

Integrated urban water management in commercial buildings.

Monitoring results are presented as an annual water balance from the pioneering Landcare Research green building containing commercial laboratory and office space. The building makes use of harvested roof runoff to flush toilets and urinals and irrigate glasshouse experiments, reducing the demand for city-supplied water and stormwater runoff. Stormwater treatment devices also manage the runoff from the carpark, helping curb stream degradation. Composting toilets and low-flow tap fittings further reduce the water demand. Despite research activities requiring the use of large volumes of water, the demand for city-supplied water is less than has been measured in many other green buildings. In line with the principles of sustainability, the composting toilets produce a useable product from wastes and internalise the wastewater treatment process.

Conventional and alternative water supply systems: a life cycle study

Research on urban development to date has tended to focus on buildings and their performance in terms of associated energy and environmental impacts. Although, many detailed studies of residential buildings have been carried out, these studies usually concentrate on the house itself without consideration of the infrastructure systems. Alternatives to traditional infrastructure systems are necessary due to increasing demand for sustainable development. Life cycle analysis is a tool which is capable of evaluating competing alternatives based on quantification of resource use over the useful life. This paper briefly examines the life cycle performance of reticulated water supply and rain tank systems used for urban residential developments in New Zealand and suggests that current consumption is an impediment to more sustainable choices. The analysis is based on life cycle energy, environmental impact and cost, using computer simulation.

Sustainable Transport: A Comparison of Ecological Footprint and Travel Patterns in Three Cities in Vietnam, New Zealand and Finland

There have been many debates on how to reduce the environmental impacts of travelling. Common suggestions are: increasing urban density, reducing travel distance to walkable and cyclable distances, using more public transport and so on. However, there is growing evidence which reveals that it is still unclear how urban form and density can be associated with travel distance. Hence, this article explores what forms the largest part of individual transport footprint in terms of domestic travel and the reasons why. Using ecological footprint measurement, this article will examine the environmental impact of domestic travel in three different cities: Hanoi in tropical Vietnam, Wellington in temperate New Zealand and Oulu in cold Finland. The argument is that the mode of travel is what should be the focus in order to reduce transport footprint, and high-density settlement is meaningless if travel still largely depends on the car. In the future of sustainability, people do not have to reduce travel distance within the city, but they do need to make smarter choices of travel.