Rush-hour traffic gridlock in Birmingham city centre will not improve unless commuters ditch their cars during the six week tunnel closures, officials have warned.

City transport chiefs hope long delays on the A38 Aston Expressway and Bristol Road will ease as commuters adjust to the full closure of the St Chads and Queensway tunnels under the city centre.

The first weekday rush hour of the school summer holidays yesterday saw traffic queueing back along the Expressway to the M6 and similar problems approaching the city centre from the south along Bristol Road.

The Queensway tunnels are closed for a second summer of major works and are due to reopen on September 1.

Last year's six-week closure was hailed as a success as many took heed of the warnings and used public transport which kept traffic flowing.

As a result, the city council's highways contractor Amey said there might have been some complacency among commuters this year but it expected the rush-hour problems to ease over the next few days as drivers got the message.

Contract manager Eddie Fellows said: "It's been very much as expected, there was some congestion on the A38 northbound into the city and the Aston Expressway.

"Given a couple of days, we expect this to settle down as they did last year. There is an element of complacency after it all worked so well last year.

"What will help is if more people use public transport or, if they have to use the car, vary their times if possible."

He said that, apart from a few minor tweaks, they were happy with the traffic management and would make no major changes.

The works this time include upgrades to the ventilation systems to pump pollution and fumes away, new electronics, information and security systems.

During last summer's closures, a huge number of people switched from their cars to other methods of travel.

Over 200,000 additional journeys were made by bus, rail, cycling or on foot.

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