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Climate Action 2011-2012

special feature autodesk

special feature autodesk CA2011 Exxaro_2.pdf The role of modelling for sustainable cities Cities, where the majority of people now choose to live, have become antiquated structures bursting at the seams and subject to some of the worst effects of climate change. Yet advances in conceptual urban planning design and building information modelling (BIM) now enable urban planners to model multiple scenarios, so that they can assess the resilience of various plans to the three-pronged challenge of changes in resource availability and demand, a changing climate, and demographic shifts. Unprecedented Urbanisation For the first time in human history, over 50 per cent of people live in cities (UN Population Fund, 2007) and, by all accounts, this percentage will only continue to grow. From an urban population of one billion in 1960, it took 25 years to add the second billion and only 18 to add the third. And if projections prove correct, the fourth billion will take just 15 years. This trend is being driven primarily by India and China. Never before in history have two of the most populous countries urbanised at the same time, and at such a pace. According to Dobbs and Sankhe in McKinsey Quarterly (2011), between 2005 and 2025, India will need to add roughly 800 million square metres of floor space and 400 km of metropolitan rail annually. In that same time period, China will need to add 1,800 million square metres of floor space and 1,000 km of urban rail. climate change front line According to World Bank research, cities account for up to 80 per cent of the expected US$80–100 billion per year in climate change adaptation costs. But the necessary adaptive measures will not be straightforward, because the combined impacts of urbanisation and climate change are not straightforward. For example, one 2011 study by Felix Eigenbrod and others, in Britain, estimates that denser populations will reduce natural water drainage, swelling rivers that are within flooding distance of millions of urban dwellers. But from the other point of view, these denser populations leave more space for agricultural production and carbon storage, essential infrastructure for any hungry and energy-intensive city. antiqUated infrastrUctUre The Organisation for Economic Co-operation and Development (OECD) estimated in 2007 that about US$71 trillion, or about 3.5 per cent of the global GDP, will have to be invested by 2030 in order to improve the basic infrastructure worldwide – including road, rail, Near photo-realistic rendering of a city model with conceptual design for a bridge and waterfront park. Designed and rendered in Autodesk ® 3ds Max design software. 152

CA2011 Exxaro_2.pdf telecoms, electricity, and water infrastructure. Most countries plan on spending far less than this amount. For example, US cities struggle with the dual challenges of water consumption and water quality. According to the American Water Works Association, most water infrastructure in the USA was installed in the late 1800s, the 1920s, or just after World War II. Since then, water use has increased dramatically, and pressure has built inside old pipes. Hotter average temperatures dry the soil, causing it to shrink away from the pipes, allowing them to burst. In cities located far from renewable water supplies, water must be transported over distances, which leads to more leaks. The Mayor of Houston, Texas, recently initiated water rationing because leakage rose from 200 leaks per day to 700 per day this summer. Compounding this challenge of water availability and waste is the issue of quality. Our cities have grown so much since their water infrastructures were built that there are far more impervious surfaces, leading to more stormwater runoff and surface pollution. This growth – combined with trace pharmaceuticals now found in our water from human and livestock sources – overtaxes outdated treatment systems. the tools at hand A truly sustainable city is one that integrates with its regional environmental context; is dominated by resource-efficient buildings; prioritises redevelopment, urban infill, and multimodal transit-oriented development; creates minimal water pollution and solid waste; makes affordable clean energy available through efficient siting and distribution; and provides a high quality of life with security for all its citizens. But, to respond to the three-pronged challenge mentioned in the first paragraph and adapt existing cities – and plan future cities – to fit this description, urban planners and regional government bodies must juggle multiple factors: • Plan for future growth to support rapid urbanisation of our global population; • Repair and revitalise decaying infrastructure and urban environments; • Prepare for and help mitigate the potential risks of climate change. To that end, more than eight years ago the United Nations University and Institute of Advanced Studies recommended that city planners take advantage of the increased availability of environmental data, including geographic information system (GIS) maps, combined with highly developed simulation tools. Fortuitously, those tools have come a long way in the past decade. As outlined in Environment Industry Magazine, Aug/Sept 2011, “We now have the ability to visualise complex urban systems on a computer before these systems are constructed; and we can optimise them, not only for construction efficiency but for subsequent operations to continue to advance. The application of modelling to entire segments of urban areas enables us to visualise the construction of multiple complex horizontal and vertical Color-coded city model showing how Autodesk ® Infrastructure Modeler 2012 software can be used to theme existing GIS data. systems in real-time 3D, project this into the future (4D), and incorporate multiple levels of information and data, including financial implications (5D).” BIM is an intelligent model-based process that provides insight for creating and managing projects faster, more economically, and with less environmental impact, throughout each of the four phases in urban planning and infrastructure design: • Plan more confidently by evaluating existing conditions and communicating the potential impact of projects; • Design and document more productively, streamlining time-consuming design tasks with specific tools and configurable standards; • Build more reliably by helping to identify costly design and scheduling conflicts before breaking ground; • Manage infrastructure more dependably with intelligent industry models to help enforce data quality standards and support future decision-making. Indeed, a team of researchers at University of California, Berkeley, are using such tools to design a similar quilt of green spaces starting with publicly owned abandoned urban sites. the Urban ecologist Investing in training and technology to drive sustainable cities creates sustainable job growth. US employment in the profession of urban and regional planning is projected to grow faster than other professions, according to the US Bureau of Labor Statistics. We should particularly reward those who manage to combine the theory of smart growth and policy design with the experience in geographic information system (GIS) and BIM tools – perhaps from one of a new crop of Master’s programs in Sustainable Urban Planning. After all, it is the 25-year-old urban ecologist upon whom we pin our hopes for future-proofing our cities. Autodesk and 3ds Max are registered trademarks of Autodesk, Inc. Dr Emma Stewart Senior Industry Manager, Sustainability, Autodesk Autodesk, Inc., 111 McInnis Parkway, San Rafael, CA 94903, USA Web: Data © City of Vancouver 153