Perspectives on Transport Management from London, Stockholm & Paris

1. Perspectives on Transport Management from London, Stockholm & Paris Rémy Prud’homme (Un. Paris XII) Imperial College, London, Jan. 17, 2007

2. Three urban transport policies Much publicized • London: an area toll in a small (3% in pop.) part of the agglomeration • Paris: a reduction in road space in a larger (20%) part of agglomeration • Stockholm: a cordon toll in a similar (15%) part of agglomeration Lessons from such policies

3. An apparent success ? In all three cases, stated objective of traffic reduction achieved, by some 15% For the media: enough to call it a success Take a second look

4. Two effective benefits in London & Stockholm time gains + environmental gains Unit costs Surplus loss S(q) I(q) B Time gain c1 A c2 D(q) Toll Quantities q2 q1

5. No Benefits in Paris Road space reduction No time gains, only time losses Time loss I2(q) I1(q) c2 c1 D(q) q q2 q1 No environmenal benefits either

6. Magnitude of time benefits Very real, but relatively small: in M£/yr • in London: 60 - 10 (surplus) = 50 net • In Stockholm: 11 - 5 (surplus) = 6 net Two comments: 1) = congestion costs. Relative to GDP of area: 0.1% in London, 0.02% in Stockholm 2) Much less than toll proceeds (1/5 in London, even less in Stockholm)

7. Minus: implementation costs • Enormous in London : 500 M£/yer • High in Stockholm : 100 M£/yr In both cases : eat up the decongestion benefits

8. Minus: public transport congestion costs PT congestion exactly like road congestion. Replace time loss by confort loss More PT users —> increase in PT congestion, for all PT users Poorly known. In Stockholm, data suggests increase in PT congestion costs = road decongestion costs

9. Conclusions • Road congestion costs vastly exagerated. • Can be reduced by tolls. A good policy when and if : a) congestion is severe, b) implementation costs are low c) PT congestion is moderate, or costs of PT supply increase are low 3) Paris road supply restriction policy worst