Motorists are being warned to expect delays on the East Lancs and Rainford bypass tomorrow evening.
Highways chiefs say drives should avoid the area on Thursday evening while engineers carry out a full survey of the carriageway.
Traffic Management will be in place overnight during the hours of 10pm on Thursday, January 26 until 6am on Friday, January 27.
Delays should be expected during these hours and drivers are encouraged to find an alternative route.
To find out about roadworks in St Helens, visit www.sthelens.gov.uk/traffic-travel-parking/roadworks/