Site preparatory work for a major upgrade on the M25 between Kent and Surrey will start next week.
Main construction work is expected to start next spring on the managed motorway scheme being built by the Connect Plus consortium of Balfour Beatty, Skanska, Atkins and Egis.
Highways Agency project manager John Martin said: “The preparatory work is vital if we are to deliver this important road upgrade as soon as possible and realise its benefits for the economy.
"As well as installing important equipment that will be used during the scheme, we are preparing key parts of the road infrastructure for the upgrade, including checking and refurbishing more than 1,000 drainage gulleys and chambers under the hard shoulder to minimise the risk of unplanned disruption once the roadworks get underway.”
The work will be carried out overnight and will include clearing some vegetation from the hard shoulder and work to relocate protected wildlife from the road verge.
The hard shoulder and sections of the verge will be strengthened, drainage will be upgraded and the breakdown recovery stations and cameras that will be used during the roadworks will be prepared.
It will be followed by an upgrade to the central reservation barrier, which will begin in November, using 24-hour narrow lanes and a reduced 50 mph speed limit.