410 likes | 957 Views
The value of urban design – avoiding infrastructure mistakes. ANZSEE Conference 2005 12-13 December 2005. © Ralph Chapman Victoria University of Wellington ralph.chapman@vuw.ac.nz Not to be reproduced without the author’s permission. Outline. Context Sustainable development
E N D
The value of urban design – avoiding infrastructure mistakes ANZSEE Conference 2005 12-13 December 2005 © Ralph Chapman Victoria University of Wellington ralph.chapman@vuw.ac.nz Not to be reproduced without the author’s permission
Outline • Context • Sustainable development • Urban design – in NZ and overseas • Transport infrastructure decisions in NZ • Framework • Why design matters for infrastructure costs and benefits • Empirical evidence • Compactness • Mixed use and connectivity • Other elements: safety, local character, the public realm • Areas for further investigation • Conclusions
1: Context“First we shape our cities and then they shape us” – Winston Churchill
A ‘sustainable development’ view • Holistic / integrative • well-being, not just economic development • complementarities as well as trade-offs • should fully ‘internalise’ environmental and social externalities • Long-term / intergenerational • concern about irreversibilities • should adequately address patterns of disadvantage – e.g. the long-term determinants of health • Redesign, rather than just ‘protect’
Well-being – including personal health Culture Environ-ment Economic conditions Social influences Schematic diagram of key influences on well-being
Urban design & transport • NZ Transport Strategy clearly SD oriented • Released (02) before burst of work on UD • Issues and aims (NZTS): • Economic development • Safety • Access and mobility • Public health • Environmental sustainability • E.g. “Walking and cycling for short trips will be promoted and reduced dependence on private vehicles for mobility is encouraged”
Urban design internationally • In US • Smart growth • New Urbanism • In UK and Europe • CABE • PoW Trust – Found’n for Built Environment • Office of Deputy Prime Minister • Urban renaissance studies (e.g. OECD, ’03)
US picture • Time spent in traffic up over 200% since 1980 • Miles driven up 10% in last decade • Source: Smart Growth America
Infrastructure influenced by urban design • Facilities: e.g. shopping, educational • Housing • Water and sewerage • Energy • Transport
A simple model linking urban design, transport and well-being Urban design Transport Well-being
A more complex model: illustrating one of the important links between urban design elements and impacts on well-being Density Health benefits Connectivity Increased physical activity (e.g. walking and cycling) Local character Other social and economic benefits Mixed use Public realm Environmental benefits Greenery
Framework principles (1) • Transport infrastructure decisions should maximise overall well-being (not individual mobility / GDP / etc.) • The transport ‘market’ is highly distorted • individual motorist decisions and preferences are highly distorted • E.g. provision & price of carparking affects car use • Thinking “It’s what people want” is misguided • Urban form / land use & associated infrastructure decisions may constitute the biggest distortion • Once decisions are made, urban development is heavily path-dependent
Framework (2) • Central and local government are, and must be, involved in transport funding (infrastructure) plus regulation, pricing & education • Market signals can still be used – but are not enough • Policy (e.g. infra) decisions should be long-term and holistic • In evaluating transport infrastrucutre options, critical to consider the whole range of costs and benefits • Include external costs and benefits of transport use • E.g. climate change impacts; health impacts • Focus here is on impacts on well-being in urban places
3: Some empirical evidence • External costs of transport: overlooked costs • Compactness of cities and well-being • Mixed use, connectivity, and well-being • Other elements: safety, local character, the public realm…
Authors Graeme McIndoe Ralph Chapman Chris McDonald Gordon Holden Philippa Howden-Chapman Anna Bray Sharpin Peer review and assistance Jenny Dixon Chris Dempsey Clive Anstey Margot Schwass Client group Frances Lane Brooker Erica Sefton Brenna Waghorn Ernst Zollner
Some external costs of transport – data from the EU, Norway and Switzerland, 1995 Source: Dora and Phillips (Eds) (2000) – for World Health Organisation
Transport market distortions: an estimate of the size of external costs size (per vehicle-mile; the US; 1990s data) Source: Litman (1999) Transportation market distortions: a survey
Other evidence on externalities… Pollution • In large European cities, up to 60.000 deaths/year caused by long-term exposure to air pollution • In US, vehicles account for ~ 30% of NOx and 44% of PM10 emissions • EPA (US): >120 m live in areas with unhealthy air • Fisher (NZ): 70 - 90 % of NZ air pollution is from vehicles Water pollution • Vehicles main source of urban run-off to water: 21% of lakes, 12% of rivers & 46% of estuaries impaired due to urban run-off
Evidence on externalities – and flow-ons Noise For ~10m in Europe, environmental noise results in hearing loss Total health burden 15-20% of burden of poor health in developed nations due to environmentalfactors, including transport impacts (EU Commission, 2004)
Compactness and well-being – divergent views • “Low-density settlement is the overwhelming choice [in the US] for residential living.” – Gordon and Richardson (1997) p96 • “Our principal conclusion is that we can only increase the ‘carrying capacity’ of urban areas – through density or mix – if we reduce the need for car travel.” - Urban Design Task Force [UK] (1999) p107
Compactness and well-being • Compactness associated with • lower infrastructure costs • Lower energy use and CO2 emissions • Lower transport costs • More physical activity • Improved health
Compactness and infrastructure costs • Archer (1973) - US: leapfrog development higher costs (both private and public) • Ewing (1997) – US: higher costs due to loss of economies of scale • US EPA (2001) - clustering can reduce costs for developers – by requiring fewer miles of roads, water and sewer lines • Muro and Puentes (2004) – US survey: smart growth saves on infrastructure relative to low-density sprawl
Compactness and energy use • Newman and Kenworthy (2000) – 38 cities globally: link betw. energy use & density • Kenworthy (2003) – 84 cities: in the high income cities, “82% of the variance in car passenger kms per capita and 78% of the variance in per capita private passenger transport energy use is explained by urban density” • Buxton (2000) – Melbourne: higher densities associated with transport energy reductions
Compactness and transport use • Holtzclaw (1994) – California: higher density levels reduce distance driven per household • Ewing (1997) – various US studies: people drive more in more sprawling urban areas • Urban Task Force (1999) – UK: density affects car use and energy efficiency • Litman (1999) – Nth America: peripheral locations increase car trips (& fuel use)
Ewing: commuting by transit is higher in most compact cities
Compactness and physical activity • McCann & Ewing (2003) - (US) sprawl & walking • Ewing (2005) - (US)sprawl and active travel • Dieleman et al (2002) - (Neths) Density acts with other factors e.g. quality of public transport, in influencing transport choices • Frank et al (2003) – (US) effect of density may be non-linear: critical threshold before walking & cycling feasible
Compactness and health • Frank et al (2003) – US: A range of urban design factors affect health • McCann and Ewing (2003) – US: direct relationship betw. sprawl and hypertension • Frumkin et al (2004) – US: overweight associated with sprawl; sprawl also associated with air pollution – in turn linked with diseases
McCann and Ewing: Urban sprawl is associated with driver body weight (448 US counties)
Mixed use, connectivity and well-being • Mixed use (US) - Frank and Pivo (1995): more mixed use is linked to fewer single-occupancy car trips • Mixed use and car use (Wales) – Van & Senior (2000) : mixed use encourages w&c; discourages cars for light shopping • Mixed use, connectivity, density (US- Atlanta) – Frank et al (2004): more mixed use associated with less obesity • Interactive effect - US (San Diego) - Saelens et al (2003): mixed use is one of the factors influencing neighbourhood walkability • Mixed use works synergistically - Frumkin et al (2004)
Other urban design elements: Safety, local character… • Interaction and traffic - Donald Appleyard (1981) & Bruce Appleyard (2005) • Traffic and injury - Roberts et al (1995) • Meta study: accessibility, aesthetic attributes & activity - Humpel et al (2002) • Neighbourhood characteristics (US) - Boslaugh et al (2004)
Final comment – Peter Hall • “The key must be to use pricing as a mechanism, but to combine it with physical and other restrictions on car use in congested or polluting conditions, so as to bring about a significant reduction and a transfer both to public transport, and to zero-energy, zero-emissions walking and cycling. At least for the immediate future, the objective is to slow the growth of car use, rather than to halt it. We know this is realistic because a few cities that have been visionary and bold have achieved something…” - Hall (1998) p968
Areas for research • What urban redesign has most effect on well-being dimensions? • What matters most in New Zealand? • Use natural experiments or policy initiatives already underway • Study changes in behaviour when conditions change
Conclusions • Think very seriously before investing in any major roading infrastructure: we now have the basis for avoiding costly infrastructure mistakes • Consider the external costs of transport • Consider the range of benefits of good urban design • Increasingly good empirical evidence available • Cities that are better designed demonstrate better performance in terms of a range of well-being dimensions, e.g. physical activity / health • Urban redesign for sustainability will be a long process – let’s pursue it.