The Highways Agency has released a time-lapse video of work to make it quicker and easier to pay the toll for using the Dartford Crossing between Essex and Kent.
The video shows the installation of five new gantries that have been installed at the entrance to the Dartford tunnels and on the Queen Elizabeth II bridge.
The gantries will hold cameras and sensors for the new Dart Charge being introduced in October. That will allow drivers to pre-pay the charge or pay online so they won't need to stop at the toll booths.
The Highways Agency says 170,000 vehicles a day use the crossing and the new system will improve journeys and reduce congestion.
Drivers are being warned the M25 anti-clockwise will be closed during Thursday's rush hour after a lorry fire.
The M25 is closed anti-clockwise between junction 23 (access to the A1(M)) and junction 21a (access to the M1).
A lorry carrying cooking oil and foodstuff has overturned, spilling its content – which later caught fire – onto the carriageway.
Emergency services are currently on scene, as well as structures engineers assessing damage to the road and overhead gantry.
A police investigation is underway. The road will be reopened as soon as it is safe to do so but the closure is expected to last for several hours, and during rush hour.
Road users wishing to use the M25 anti-clockwise need to exit the M25 at junction 23 and take the A1(M) north; exit at junction 3 and join the A414 west. Take the A405 south and rejoin the M25 at junction 21.
The M25 at Aveley between junctions 29 and 30 was fully reopened at 9pm last night, following a fatal collision involving ten vehicles. The collision happened at 12.30pm on the clockwise carriageway and involved four articulated lorries and six cars.
One person, a man in his 70s from east London, was certified dead at the scene. Two people were airlifted to the Royal London Hospital and a number of other people received less serious injuries.
Two lorry drivers were arrested at the scene on suspicion of causing death by dangerous driving. A 43-year-old man from Poland was later released without charge, while a 58-year-old man from Germany remains in police custody.