Effect of London Congestion Charge Scheme On Traffic ... - IAPSC

Congestion Charging inCentral London:Air Quality ImpactsCharles BuckinghamCongestion Charging DivisionTransport for London

Background• Central London context• Mayor of London - Strategies• No. 1 priority - tackling congestion• Introduced congestion charging scheme in firstterm - 17 th February 2003• 10-15% less traffic, 20-30% less congestion• Commitment to monitoring• Focus on revealed air quality impacts• Scheme outline and operation….

Congestion Charging Zone

Projected impacts• Reduce traffic inside charging zone by 10-15% and 2-3% in Inner London• Cut traffic delays by 20-30% inside chargingzone and 5-10% outside• Traffic speeds increase by 10-15% insidecharging zone and 2-4% immediately outside• Help bus operations• Improve journey times and reliability• Net revenues of c.£100 million per year

Air Quality Impacts• Congestion Charging NOT specifically directedto improving air quality• BUT changes to volume and characteristics oftraffic will AFFECT air quality

Main Traffic Effects• Less traffic. Reductions of c.15% overallduring charging hours. Minimal effects atother times and outside of charging zone.• Traffic moves more efficiently. Increasedspeeds (up 17%), reduced congestion (30%)and less queueing time (30%).

Key Traffic Changes250,000200,000Feb / Mar 2002 May / Jun 2002 Sep / Oct 2002 Jan 2003Feb / Mar 2003 May / Jun 2003 Sep / Oct 2003Total flow150,000100,00050,0000Cars Vans Lorries &OthersTaxisVehicle typeBus & Coach Motorcycles Pedal cycles

543210Congestion in the Zone zoneCongestionNighttime travel rateJun/Jul 94Jun/Jul 97Jun/Jul 00Jan/Feb 02Mar/Apr 02May/Jun 02Jul/Aug 02Sep/Oct 02Nov/Dec 02Jan/Feb 03Mar/Apr 03May/Jun 03Jul/Aug 03Sep/Oct 03Nov/Dec 03Jan/Feb 04Survey periodJun/Jul 90Jun/Jul 86Travel rate (min/km)

Time spent at various speeds4035May/June 2002May/June 2003Length of time (hours)3025201510500-10 10-20 20-30 30-40Speed bands (km/h)

Main Air Quality Effects• Less traffic -> Less fuel -> Less emissions.• Faster average speeds and less queueing ->greater efficiency per unit distance travelled.• Changes to vehicle mix - a variety of effects,not all of which are ‘good’• Background changes - such as fleet turnover,new buses etc.• BUT direct effects on ambient AQ unlikely tobe detectable in short-medium term

EmissionsPercentage change in relation topre-charging base (100%)ChargingzoneChargingzoneInner RingRoadInner RingRoadNO x PM 10 NO x PM 10Volume change - motorcycles 0 +1 0 +1Volume change - taxis +1 +3 0 0Volume change - car -6 -4 +1 +1Volume change - bus and coach +4 0 +3 0Volume change - light goods -1 -2 +1 +2Volume change - rigid goods -2 -1 +1 0Volume change - articulated heavy0 0 0 0goodsSpeed changes (all vehicles) -8 -9 -4 -5Percentage change due to trafficand speed changesEmissions factors (fleet turnover andtechnology mix)-12 -12 +2 -1-4 -4 -6 -5Overall traffic emissions change -16 -16 -4 -7

450400350300250200150100500Running annual mean NO xSuburban London control Background surrounding zone Background within zoneRoadside approaching zone Kerbside on boundary Roadside within zoneProvisionalDataJan-99May-99Sep-99Jan-00May-00Sep-00Jan-01May-01Sep-01Jan-02May-02Sep-02Jan-03May-03Sep-03Sep-98Running annual mean (µg/m 3 )

Running annual mean NO 2Suburban Outer London Inner London - Background Within Charging Zone - BackgroInner London - Roadside Inner Ring Road - Roadside Within Charging Zone - Roadsid120ProvisionalData100Running annual mean (µg/m 3 )806040202005 air quality objective level (40µg/m 3 )0Sep 98Jan 99May 99Sep 99Jan 00May 00Sep 00Jan 01May 01Sep 01Jan 02May 02Sep 02Jan 03May 03Sep 03

180160140120100806040200PM 10 - Exceedence DaysSuburban London control Background surrounding zone Background within zoneRoadside approaching zone Kerbside on boundary Roadside within zoneProvisionalData2010 air quality objectivelevel (10 days)2005 air quality objective level(35 days)Jan-99May-99Sep-99Jan-00May-00Sep-00Jan-01May-01Sep-01Jan-02May-02Sep-02Jan-03May-03Sep-03Sep-98Number of days where daily mean >50µg/m 3(running annual mean)

Comparative Wind Rose31033032030002500200001020304050Wind direction histogram(count of readings in each 10 degree bin)30029028015001000500607080340 350 March to November 2001March to November 2002March to November 2003270090260100250110240120230130220210200190180170160140150

Perceived environmental andtransport qualityTraffic congesion Autumn 2002Car speedCar reliabilityAutumn 2003Public transport provisionBus speedBus reliabilityUnderground speedUnderground reliabilityAir qualityNoise1 Very 2 3 4 Very 5PoorGoodSource: TfL On-Street Public Space Surveys