In 2007, the Transport for London (TfL) stated that between 2003 and 2006, NOX emissions fell by 17 percent, PM10 by 24 percent and CO2 by 3 percent, with some of this improvement being attributed to the effects of better traffic flow, and the rest of the improvements, a result of improved vehicle technology.

August 2008

Summary Information

The report "Lessons Learned from International Experience in Congestion Pricing", prepared in August 2008, provides a summary of selected operational area wide congestion pricing projects outside the United States. This report provides findings and draws lessons from a sample of projects with the richest and most relevant experience, focusing on three comprehensive area wide projects: Singapore, London and Stockholm. Each received in-depth attention during planning, design, implementation and operational phases and have been monitored and evaluated carefully. These projects should be of particular interest now that several U.S. cities are beginning to examine similar area wide pricing strategies to address congestion, environmental, energy and funding problems in heavily congested downtown areas.

Research on acceptability is especially detailed in these international locations and provides valuable lessons for U.S. cities interested in pursuing such policies. The report concludes with overall findings and lessons related to travel, costs and revenues, equity and economic impacts, environmental impacts; and public acceptance. These projects have demonstrated that pricing can be an affective means of managing demand and generating revenues and can be politically and publicly acceptable.

Findings from London

The Congestion Charging program in London commenced in February 2003. It covered the 8.0 square mile, heavily congested central business district. The charging zone represented less than 1.5% of the total area of Greater London with a population of about 7.0 million. Subsequently, the charging zone was extended to the west to cover an additional 8.0 square miles including Westminster, Kensington and Chelsea. The overall program package included a 40 percent increase in capacity of buses and trains by 2011 starting immediately with expansion of bus service.

London Congestion Charging has accomplished its stated objectives.

The reduction of airborne emissions wasn't listed as one of the reasons for introducing the congestion charge. The pre-commencement report from the Transport for London (TfL) noted that the scheme wasn't expected to significantly affect air quality, but that offering a discount to encourage the use of greener fuels would be a positive measure. However, TfL has reported changes in air quality within and alongside the Inner Ring Road boundary of the zone.
  • Levels of NOX fell by 13.4 percent between 2002 & 2003, CO2 by 15 percent, and particulates (PM10) by 7 percent.
  • TfL (2007) states that between 2003 and 2006, NOX emissions fell by 17 percent, PM10 by 24 percent and CO2 by 3 percent, with some improvements being attributed to the effects of better traffic flow, and the majority being as a result of improved vehicle technology.
  • In total, the rate of fall in CO2 has been 20 percent. The TfL report makes it clear, however, that only the initial reduction of emissions could be expected from the introduction of the charge. Further reductions are unlikely to be as a result of the charge. Although no areas within the Congestion Charge Zone reported NO2 levels above an upper limit of 200 μgm-3 (105 ppb), some monitoring areas near the zone boundary experienced very long periods at such levels.
TfL reports that emissions may not necessarily feed through into improvements in air quality and that vehicle emissions are only one contributor to total emissions of a particular pollutant along with weather conditions and industrial use. It was also reported that pollutant concentrations were being affected by the change in the make up of the vehicle fleet. The TfL continues to study the effects of the charging program on air quality.

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Lessons Learned From International Experience in Congestion Pricing - Final Report

Author: Kiran Bhatt, Thomas Higgins

Published By: U.S. Department of Transportation, Federal Highway Administration

Source Date: August 2008



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Benefit ID: 2010-00622