Motorists face Olympic gridlock as the first three days of the sporting extravaganza could be crippled by jams chaos, a report by leading traffic experts has warned

Drivers and commuters will be hardest hit as jams and journey times increase by a third, traffic on key routes slows to just 12 mph, and rush-hour traffic peaks 90 minutes earlier at 5.30am and 3.30pm, adding an average 20 additional minutes to a one hour journey.

The dire prediction is made comes from traffic experts INRIX .

The situation – first highlighted by this newspaper more than five years ago �– could be even worse and double to 40 minutes in the worst cases.

They even warn that the Olympic opening ceremony could be held in a half empty stadium because the other half are stuck in a jam still waiting to get to Statford..

The report highlights how the “perfect storm” of traffic chaos could hit.

While Newham has been basking in the new developments that could bring lasting improvements to local life, there has always been the feeling among local people and business men and women that the main local road arteries, the Romford Road, Barking Road and A13 Newham Way cannot cope now, let alone with the Olympics traffic.

We remember the chaos caused when there’s a breakdown in the Blackwall Tunnel, or how locals were trapped when a gas leak kept people inside the Beckton Triangle two years ago…or even the gridlock of the Jean Michel Jarre concerts in the 80s.

The report predicts a “perfect storm” of traffic gridlock.It highlights how the Olympic opening ceremony on Friday July 27 clashes with one of the busiest holiday getaway weekends of the summer when traffic levels are already around 30 per cent above average.

The report said: “The first three days of the event pose the greatest risk of traffic troubles. The combination of high expected attendance figures, extensive road closures and normal holiday getaway traffic with a road user population in the early stages of learning how to cope with changes to normal traffic flows caused by events means the event could get off to the worst possible start.”

INRIX is the firm which provides real-time traffic information to hundreds of sat-nav and mobile phone providers, including car giants such as Ford, Audi, Nissan Toyota, and to the BBC.

It is based on its detailed data of current historic traffic flows gathered over many years - including disruption caused by major sporting or cultural events - combined with their prior diary knowledge of Olympic and other events planned this summer.

The INRIX report notes how the Government and Olympic planners are relying on city workers switching to public transport, staggering their journeys, or working from home, to ease congestion.

“‘If there is at any stage a failure of the transport system to cope with the demands put on during this period there is a danger that this could be the lasting memory… rather than the sporting excellence achieved by the athletes.”

It says there is also the danger of a domino effect of congestion routes near to the M25 blocking key junctions and preventing access to and from the motorway is clearly a significant risk.

The men’s and women’s road cycling events are also being held over that first Olympic weekend.

The report said: “The organisers are therefore at significant risk of having the first three days dominated by stories of serious traffic problems – a ‘Perfect Storm’ of traffic congestion.”

Transport for London said that the problems on London’s roads would not be anywhere near as bad as Inrix suggests.

When sending tickets to spectators, TfL will give people information on the best way to get to venues using public transport.

Millions of pounds have been spent on improving the infrastructure of the capital and it is hoped this will be enough to mitigate any major problems.

TfL is relying on people planning for the Games and hopes that commuters will heed warnings and take public transport to get to work rather than using their cars.

Journeys through Games ‘hotspots’ such as Vauxhall Bridge and the key Blackwall Tunnel – linking the main Olympic village to the North Greenwich Arena (O2) - will take at least 15 minutes longer.

Olympic planners hope 80 per cent of visitors to the main Games park will arrive by public transport, using park and ride schemes

Garrett Emmerson, chief operating officer for surface transport at TfL, said: “The findings in this report are without foundation and are based on false assumptions, incorrect, out of date information and is packed full of factual inaccuracies.

“It is unclear how INRIX has reached the conclusion that congestion will increase on the Olympic Route Network during Games time, when the purpose of the ORN is to achieve reliable journey times and improved traffic flow for the athletes, officials and others working to put on the Games.

“TfL has spent the last six years planning for the Games. The traffic flow, vehicle trips, congestion hotspots and journey times data we’ve collected has helped us build an accurate picture of what the impact will be on London’s streets during Games time, which we have already published on our website.”