ENGINEERS will begin work to drill 100ft-deep holes into the ground by the M6 at Orrell on Monday.
The dramatic excavations are the prelude to a major project to reduce congestion and improve safety at the junction.
The Highways Agency scheme will see three temporary drilling rigs set up by junction 26, which links the motorway to the M58 and the A577. Engineers need to carry out tests on the land as the motorway was built in a former mining area.
The project, expected to last for three weeks, will require the southbound entry and exit slip roads to be closed from 10pm until 5am each night. The roundabout by the slip roads – to the east of the motorway – will also be closed, preventing access to the M58 and A577.
The work is taking place overnight under lighting towers to minimise disruption and there will be no impact on the main motorway carriageways, although there will be some noise from the rigs. Clearly signed diversions will be in place for motorists affected by the slip road and roundabout closures.
The investigative work is being carried out ahead of a £1.7m Highways Agency project due later this year which will see extra lanes added to the southbound exit slip road from the M6 and the northbound link road to the A577.
New traffic lights will be installed at the southbound roundabout to improve traffic flow, with sensors monitoring the number of vehicles approaching from each direction. Highway Agency project manager Philip Tyrrell said: “Anyone who regularly uses junction 26 on the M6 will know how busy it can get at peak times, with traffic often queuing to get onto the M58.
“We need to carry out investigative work by the junction over the next few weeks before we can start a major project to improve the junction later in the year.
“All of the tests will take place overnight when fewer motorists are using the junction, and they’ll be clearly signed diversions to help people continue their journeys.”
The project is one of 123 in the Government’s £317m “pinch-point” initiative, devised with the input of councils and local enterprise partnerships, and is designed to help stimulate new development and local economic growth by improving road safety and tackling congestion bottle necks.