The closure marks the first time in the M25’s 38-year history that a stretch of the motorway has been closed to traffic for an entire weekend.
National Highways has set out a diversion route that more than doubles the five-mile distance between the two junctions, warning of delays of up to an hour.
Motorists will be forced to detour more than 10 miles around northern Surrey, via Cobham, Byfleet, West Byfleet and Sheerwater before rejoining the motorway at Chertsey, just south of the Heathrow airport stretch.
Mr Wade previously said an overnight closure would not allow enough time to remove the bridge.
‘Risk of bits falling onto the traffic’
“Neither can we just partially demolish it and come back the following night, because we can’t leave it in an unsafe condition with the risk of bits falling off it on to the traffic during the day,” he said.
Nearby trains run by South Western Railway are operating normally over the coming weekend except for a line closure between Hampton Court and Surbiton.
Other engineering work is taking place further afield but will not directly affect trains on the South West Main Line between Weymouth and London.
When asked if the work might overrun and affect Monday morning’s rush hour, Mr Wade said later stages of work could be canceled if necessary.
Delays and curtailed routes
“If, in the very early stages, we see things for any reason not going to plan, we have the ability to pull the later stages,” he said.
“The idea that it should still be closed even at 6am on a Monday morning really doesn’t bear thinking about.
“I’m as confident as I can be that the M25 will be open no later than 6am.”
Coach operators are warning passengers of delays and curtailed routes.
National Express, which connects the UK’s two busiest airports, Heathrow and Gatwick, cautioned that passengers should expect delays near the airports.