Engineers and transport bosses say a project to refurbish road tunnels which carry one of the busiest commuter routes in the country has been a success.
The St Chad's and Queensway tunnels in Birmingham are on course to reopen next week with the six week closure causing less disruption than many feared.
The maintenance of the Birmingham tunnels has led to unexpected benefits, such as as signal timings and road markings, according to an Amey UK spokesperson.
Gerry Harris says the changes could be kept on after the tunnels reopen.
Workers on the St Chad's and Queensway tunnels have confirmed that they will reopen as scheduled and in budget.
The tunnels have been closed for maintenance and upgrades since mid-July, and are due to reopen on September 2.
The closures were necessary to bring the 40-year-old tunnels up to government standards with key upgrades including new fireproofing, safety gates and led lighting.
At the outset of the project, concerns were voiced by some road users that the tunnel closures would cause traffic chaos. In fact, the minor changes made to traffic controls during the closures have been so effective that some are going to be left in place after the tunnels reopen.
Workers on the Birmingham tunnels have confirmed that the project is due to end on time and in budget.
Many motorists had feared major traffic disruption throughout the city while the works were underway.
However, changes on the network including new pedestrian crossings and altered timing on lights have allowed the work to carry on with minimal disruption to commuters, travellers and tourists.
The Queensway and St Chad tunnels have been shut throughout the summer holidays for essential maintenance. It has been confirmed they will open next Monday as planned.
Traffic has started to build up along the A38 into Birmingham city centre as the second day of tunnel repair works began.
The Queensway tunnels will be closed completely for six weeks as engineers upgrade the 40-year-old underpass system.
Motorists are advised to use the A4540 Ring Road as an alternative route.
There has been anger today from commuters stuck in traffic after the main Birmingham road tunnels were closed for repairs.
Motorists complained that buses were being given priority, causing jams.
Those behind the six-week-long scheme say buses are the best way to get people through the city and they want drivers to switch to public transport if possible.
Eddie Fellows, Highway Network Manager for Amey said traffic levels were higher in Birmingham city centre this morning due to the tunnel closures.
Speaking to ITV News Central he said: "We wouldn't have these kinds of jams right in the city centre and these are as a direct result of the tunnels, so we're still appealing to people to leave the car at home."
Commuters in Birmingham city centre today said the traffic was a "nightmare" this morning.
The A38 tunnels leading into the city have been closed for maintenance work until September.
Cars were diverted away from Broad Street leading to heavy queues of traffic.
One driver told ITV News Central: "I think in this city we're very badly served by the engineers and the traffic planners."