According to figures released by Transport for London, there has also been a 6 per cent increase in the level of traffic within the former zone while average traffic speeds have slowed by around 3 per cent leading to increased journey times for Londoners.
TfL has sought to downplay the figures, insisting all three measures were at the lower end of expectations.
TfL have also claimed the WEZ’s removal has had no ” discernible” effect on traffic-derived pollution levels.
The WEZ was removed after a consultation by TfL produced a majority on favour of scrapping the extension which had been introduced in 2007 by former Mayor Ken Livingstone.
The holding of the consultation was a manifesto commitment by Mayor Boris Johnson.
In a statement accompanying publication of the figures, Johnson said: “I’ve always believed that West Londoners never wanted the extension of the Congestion Charge and had it foisted upon them.”
“I am glad I gave the people a say and thrilled that the initial results suggest there has been no significant downside in removing the Western Extension zone.”
Commenting on TfL’s downplaying of the figures, Green Party London Assembly Member and 2012 Mayoral candidate Jenny Jones said: “An increase of nearly 10% in traffic is nothing to celebrate.
“The estimated £55m loss of income from congestion charging could have paid for lower public transport fares. Particulate pollution has been bad across the whole of central London this year and the area covered by the western extension zone is no exception. It is too early to say what the long term impact will be as the major roadworks and lane restrictions on Cromwell Road have reduced local traffic since last October.”
Caroline Pidgeon, Leader of the Liberal Democrat London Assembly Group which backed abolition of the WEZ commented: “The WEZ diluted the impact of the initial congestion charge zone and its abolition ended the perverse incentive of some of the richest Londoners being able to drive into central London yet only paying 10% of the Congestion Charge.
“But as any traffic engineer will tell you 12 weeks is a very short period of time in which to properly judge the impact of such a change, whether in terms of traffic flow or pollution.”