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French/US Workshop on the Role of Public Transport in Creating Liveable and Sustainable Communities. High speed on rail and traffic calming on road: a new deal for urban accessibility. Pr. Yves Crozet Institute of Transport Economics (LET) University of Lyon - France
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French/US Workshop on the Role of Public Transport in Creating Liveable and Sustainable Communities High speed on rail and traffic calming on road: a new deal for urban accessibility Pr. Yves Crozet Institute of Transport Economics (LET) University of Lyon - France yves.crozet@let.ish-lyon.cnrs.fr www.let.fr
Contents • 1) Accessibility: the key role of high speed modes and the relative obsolescence of car for interurban mobility • 2) Urban mobility: low speed modes and the renewal of “accessibility”
1) Accessibility: the key role of high speed modes • The iron law of coupling • Microeconomic optimisation and interurban mobility
Global mobility (data points : 1960-2000) 100 000 Per Capita Traffic Volume , pkm 10 000 1 000 100 100 000 1 000 10 000 100 GDP / cap, US$ (2000) Source : Schafer and Victor (2000) : economicgrowth rates based on IP CC IS9 2a/e scenario
Accessibility • “Accessibility at point 1 to a particular type of activity at point 2 is directly proportional to the size of the activity at point 2 and inversely proportional to a function of the distance separating the two points. • The total accessibility at point 1 to the activity is the summation of the accessibility to each of the points around point 1” (Hansen 1959, p. 74 ff)“
We can describe accessibility as a function of territorial structure and transport supply. • with • Ai = Accessibility to destinations D from point i • Dj = Activity destinations at points j • cij = Generalized costs (time, price…)
Accessibility and city attractiveness Transport Interurban Mobility Activities Location
Time budget Road speed HST Speed Value of Time Distance Walking Car Revenue HST Plane
Interurban mobility • There is an « iron law » of coupling • The more you increase the GDP, the more you increase mobility • A higher revenue leads us to look for « variety » and then to seize the opportunity of a higher and cheaper speed to increase our average distance of travel • Farer, faster and more often for a shorter stay!
2) Urban mobility: low speed modes and the renewal of “accessibility” • Travel time budget and speed, extensive and intensive cities • Gravity accessibility, an other combination between density and speed
Speed and distance: the reinvestment of time gains - (Zahavi’s conjecture and urban sprawl) Time WT V V’ TT Space
« Extensive » vs « intensive » cities (2) Average speed on road network (Km/h) Extensive Intensive Daily travel time budget (min) Average daily distance (Km)
« Extensive » vs « intensive » cities (1) Population (x1000) Nb of cars per 100 inhabitants Extensive Intensive Urban GDP/per C x10 US $ Surface (/square km)
« Extensive » vs « intensive » cities (3) Nb of cars per 100 inhabitants Extensive Intensive Modal share of public transport Modal share of car
Urban mobility: new challenges • France: some paradoxical changes in urban mobility policies • The decreasing relevancy of Cost Benefit Analysis (CBA) to define public choices • A public preference for slow modes (tramway, bus, bikes, pedestrian streets..) • Voluntary restrictions to car mobility (lower speed, reduced width of roads…) • Towards a lower accessibility ? A risk for urban attractiveness?
Economic theory of urban accessibility Hansen 1959, Koenig 1974 Parameter Generalised cost Sensitivity to Generalised cost « Attractive Masses » Monetary cost + Travel Time +parameters Housing Jobs Shops, Leisure
Time, distance and speed in urban areas Walking Bicycle SSB Bus Tramway Metro Car
Potential passenger flow in a dense area per hour for a 3.5 meters width infrastructure
MOSART and Lyon case study • MOSART, a GIS-T tool • Car accessibility during off peak and peak periods • Compared accessibilities (car vs public transit): the revealed preferences of public policies • From time gains to land use priorities
Shops et services • Administratives areas • Orthophotos MOSART : A GIS • PTnetwork • Road network • Census data
Project objectives • Measuring and viewing services levels offered by different transport networks • Identifying access inequalities to urban amenities • Comparing transport-policy and urban-planning scenarios • Creating Spatial accessibilities observatory
Conclusion (2) • Tell me what accessibility you are ready to promote, and how (mode ? speed ? reliablity? density?) and for who ? • Tell we what accessibility you are ready not to promote, and even to reduce… • And I’ll tell you what city you prepare for tomorrow!
Some references • Crozet y. (2009), The prospect for inter-urban travel demand, 18th Symposium of International Transport Forum, OECD, Madrid 16-18/11/2009, 28 pages, www.internationaltransportforum.org • Crozet y. (2009),, “Economic Development and the Role of Travel Time: the Key Concept of accessibility”, Commissioned paper for the 2009 VREF (Volvo research and education foundation) Conference on Future of Urban Transport: Looking for an Architecture for a Sustainable Urban Transport,Gothenburg, April 20-21, 2009, 23 pages • Hansen, W.G. (1959) ‘How accessibility shapes land-use’, Journal of the American Institute of Planners, 25, pp. 73-76 • Johannsson, B., Klaesson, J., Olsson M. (2002) ‘Time distance and labour market integration’, Papers in Regional Science, 81-3, pp. 305-327 • Koenig, J.G. (1974) ‘Théorie économique de l'accessibilité urbaine’, Revue Economique,XXV-2, pp. 275-297 • Morris, J.M., Dumble, P.L. and Wigan, M.R. (1979), ‘Accessibility indicators for transport planning’, Transportation Research-A, 13A, pp. 91-109 • Pirie, G.H. (1979), ‘Measuring accessibility : a review and proposal’, Environment and Planning A, 11, pp. 299-312
Demand Curve ? Wilson (1970) • Accessibility (Hansen, 1959)
Surplus change for zone i • Neuburger (1971) = Koenig (1974)