R. Prud

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 PARIS LIGHT TRAINIS THERE SOMETHING TO LEARN
FOR HOUSTON?

• R. Prudhomme (University Paris XII)
• M. Koning (University Panthéon-Sorbonne)
• P. Kopp (Panthéon-Sorbonne)
• Houston, May 18, 2008

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GEOGRAPHY
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(No Transcript)
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DAILY TRIPS IN PARIS AREA
Paris 2,2M P. C. 4 M G.C 4,8M
2 (23)
Paris
2,7 (58)
1,1 (63)
3 (63)
5,4 (22)
8,6 (10)
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THE TRAINS NAME IS T3
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POLITICAL CONTEXT

• Congestion, CO2
• Price versus quantity London toll, Paris, road
  diet
• Light train is a symbol of modernity.
• A political and mediatised success (mayor
  re-elected and media love it)
• Need for CBA

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T3s CONSEQUENCES

• T3 switch's riders from bus to light train
• Different groups of citizens are concerned
• PT users (T3, subway)
• Car users, on Maréchaux boulevard, radials,
  ring road
• We study the variations of their economical
  surplus (welfare approach)
• And the environmental impact (one of T3s
  objectives ).

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WHO ARE THE USERS?

• Ex-bus (50) or subway (33) users.
• Low modal shift from cars (2,7)
• 144,000 bus tripskm before
• 256,000 train tripskm today (2,56 km in average
  length) 100,000 users per day
• Time gains and comfort gains
• Decrease mobilitys price and increase welfare
  gains

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LIFE IS BETTER FOR TRAIN USERS

• Time gain. The average speed is now 20 km/h (
  before 16 km/h)
• Waiting time increased 0,5 minute
• The travel cost (in time) of a trip decrease by
  0,438 min/riderskm
• With a time value of 10,2 /h, the annual gains
  is 4,47 M
• Comfort gains. Tricky question (contingent
  evaluation, willingness to pay for comfort)
• Simplifying assumption comfort gains are in the
  same order of magnitude than those of time (4,47
  M)

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AND WORTH FOR CAR USERS

• Car traffic has fallen from 198,000 riderskm to
  116,000 riders km (-82,000)
• But Modal report Cars to T3 is low -7,000
  riderskm
• Did they disappear?
• Structural decrease (Paris public policy oil
  prices increase) -10,000 riderskm
• Real decrease in traffic 65 000 riderskm
  (-36)
• Where are the others?

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HERE THEY ARE!

• On the Ring Road Cost gap equal to the
  roundabout way plus the waste of time necessary
  to reach the ring road
• Average length of trip on the boulevard 4 km
• Roundabout way 2400 m 800 m
• Average speed 20 km/h
• With these parameters
• ?cost 0,6 min/carkm 0,102 /riderkm

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A CLEAR PICTURE
Cost
Ob
Oa
B
PB
D
C
B
PB
PA
A
D
Trips
QB
QA
QC
Stay
Out
Switch
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COST CONSEQUENCES

• Shift to Ring road, QBQC55,000 riderskm
• Mobility decrease, QCQA10,000 riderskm
• Welfare decrease - 6,85 M / year
• Wastes of time on radials - 1,83 M

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RING ROAD CONGESTION

• More cars on the ring road means more congestion
• The traffic has increased of 55,000 riderskm/day
  (42 300 tripskm/dayBC)
• Debates on congestion costs in urban areas
• With INFRAS value (2,70 /riderskm), we find an
  annual cost of 45,06 M.
• We use Prudhomme-Suns model of congestion
  (2000). It uses a  disaggregated approach  by
  distinguishing congestion costs with respect to
  the speed of displacement (Koning, 2008)

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RING ROAD COST OF CONGESTION
Speed (km/h) Distribution () Shift (vehkm) Cm(q) (/tripkm) Congestion costs (/day)
5ltxlt10 4,06 1 717 15,9 27,306
15ltxlt20 6,36 2 690 2,54 6,833
35ltxlt40 3,29 1 392 0,37 515
70ltxlt75 14,18 6 260 0,01 63 33.1M per year
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ENVIRONMENTAL IMPACT

• Two important relations
• - Number of cars and CO2 are correlated
  
• - CO2 emission is an inverse function of
  speed under 50 km/h
• Hence
• Suppression of buses (-)
• Modal report Cars/Train (-)
• Decrease car speed on Blv Maréchaux ()
• Decrease in car speed on RR ()
• Longer trips to access the BP ()

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CO2 EMISSION ON THE RING ROAD

• According to US Ministry of Energy
• If slt 50 km/h
• CO2 (kg/km) 0,624 0,00925s
• If sgt 50 km/h
• CO2 (kg/km) 0,16
• By crossing this relation with the speed-density
  relation, we can deduce the  marginal emission 
  on the ring road (function of density)
• CO2M (kg/vehkm) 0,00231q

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BAD CO2 BALANCE
Before (tons) After (tons) Change (tons)
Bus Suppression 1,065 0 -1,065
Modal report 709 0 -709
Longer trips 0 1,114 1,114
Speed decrease on Bd Maréchaux 11,787 12,538 752
Speed decrease on RR 3,023
Total 3,115 0.1M
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COSTS AND BENEFITS
Initially (M) Annual (M)
Investment -444,34
Functionning Nd
? surplus operator 0,84
? surplus users CT
Time gains 4,47
Comfort gains 4,47
Subways decongestion 4,57
?surplus car users
On Maréchaux -6,85
On radials -1,83
Externalities
Congestion BP -33,31
CO2 emissions -0,10
Total -444,34 -27,74
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WHAT DID WE LEARN?

• Negative NPV of 888 M with a 30 years horizon
• Impossible to find a positive IRR
• Environmental objective is not reached
• Car users (from poor suburbs) are the losers of
  the T3s project
• The T3 users are the winners. 60 are richer
  Parisians
• When only 15 of the cost is paid by the
  municipality, the rest by the region

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CONCLUSION

• Cities need a bundle of means of transportation,
  cars and PT
• Among PT, the choice btw subway, train and bus
  hardly rely on density
• Subway or light trains are good for high density
  zone and/or mass commuting trip
• Buses are cheaper and more flexible elsewhere

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A CONSERVER
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A CLEAR PICTURE
p
Ob
Oa
C
PB
B
PA
A
F
E
D
q
QC
QB
QA
Stay
Switch
Stop
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• Assumption the shift follows the same
  distribution law
• Speed-density relation
• V(q) 77,1 -0,25q
• Private cost
• I(q) 0,12 1,310,2/V(q)
• Social cost
• S(q) I(q) I(q)q
• Marginal congestion cost
• Cm(q) S(q) I(q) 3,315q/(77,1- 0,25q)2