It is still "one of the biggest risks" to the event, according to the London Assembly Transport Committee, which is concerned about the amount of extra transport capacity needed, the Olympic Route Network (ORN) and the reliance on people changing their normal travel behaviour for the 2012 plans to work.

Committee chairman Val Shawcross warns that London will face "extreme demand placed on a network already creaking at the seams" in 2012.

Spectactors travelling to competitions and events will get caught up in it, but residents and businesses may also notice the impact, she said.

"Regular users are likely to experience more overcrowding and queuing," according to the Committee report on 2012 transport plans.

With up to 5.3 million expected at the Games in total, more than a million Olympic-related journeys are predicted to be triggered on public transport over the busiest nine days.

This is when about 550,000 to 650,000 tickets would be up for grabs to spectators travelling to venues across London.

Despite transport improvements, with the notable exception of the Jubilee line, the network is currently running at near to top capacity and can not easily absorb extra demand.

There are also 22 anticipated "travel hotspots" in 2012, including some of London's most congested roads and Tube stations, which already suffer chronic overcrowding.

The report said: "While on a good day the higher demand may be confined to a few 'travel hotspots', in the event of a broken-down train or a security incident, there would be a wider impact.

"Demand for transport services elsewhere is also possible as people seek alternative ways to make trips.

"All regular users of the transport system are likely to notice differences in 2012. Rail and Tube passengers will experience many more delays, crowding and queuing."

Businesses and Londoners will need to consider different ways of working and travelling, including home and flexible working, travelling at different times or walking and cycling more during the Games, Transport for London (TfL) said.


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